On the 24th of September that year, a controller manning the tower’s helicopter control position — more on that in Chapter 4 — cleared a helicopter for liftoff from DCA’s north helicopter pad, which no longer exists but was at that time located just west of the departure end of runway 1. The helicopter belonged to a civilian operator that had somehow acquired the special military chart, so the pilot requested a departure via “Route 1 to Greenbelt.” I was never able to find a copy of this more than 40-year-old military chart, but if Route 1 was the same as it is today (and the evidence supports that it was), then the route presumably ran from Cabin John, Maryland, southeast down the Potomac River to Hains Point, immediately north of DCA, then northeast up the Anacostia River to Greenbelt, Maryland. Since the DCA north helipad was not located directly under Route 1, a departure via this route would have required what’s called a “transition,” in which the helicopter follows a normal agreed-upon path to, from, or between a published route or routes.[28]

The helicopter controller said that she always told helicopters departing the north helipad for Route 1 to fly northwest to the Arlington Memorial Bridge, where they could intercept the route and follow it to their destination without interfering with traffic taking off or landing on runway 1/19 (then known as runway 18/36). This transition was informal and not published on the special military chart. In this case, when the helicopter pilot asked for Route 1 to Greenbelt, she cleared the helicopter to fly as requested, but incidentally forgot to specify the transition that should be used. As a result, the helicopter pilot assumed he had been cleared to Route 1 by the most direct transition, which took him directly over the departure end of runway 36 (now 1).[28]

At the same time, the Local controller, who was responsible for issuing landing, takeoff, and runway crossing clearances, cleared an Eastern Air Lines Boeing 727 for takeoff on runway 36 without coordinating with the helicopter controller. As the 727 neared its decision speed, the pilots suddenly saw the helicopter take off from the north helipad and fly toward their projected takeoff trajectory. At the last second, the captain aborted the takeoff and slammed on the brakes. Simultaneously, the helicopter pilot saw the 727 approaching and steered hard away from the runway, back toward the helipad. Behind him, the speeding 727 ran off the end of the pavement and lurched to a stop in the grass, just 40 meters from the edge of the Potomac River.[28] By the narrowest of margins, disaster was averted.

The NTSB found that the helicopter operator didn’t have an LOA with the tower authorizing its pilots to request or accept clearances based on the special military chart, but that the controller had no way of quickly ascertaining this. Furthermore, because it wasn’t intended for civilian use, the chart only depicted standard transitions to and from military heliports, excluding civilian helipads like the one at DCA. As a result, the NTSB recommended that the FAA create a single VFR helicopter route chart for use by all helicopters in the DC area, both military and civilian.[28]

Because the special military chart is, as far as I can tell, lost media, I wasn’t able to definitively establish the closeness of the relationship between the pre-1985 military chart and the Baltimore-Washington VFR Helicopter Route Chart that the FAA published in 1986 at the behest of the NTSB. However, I have plenty of reason to believe that the helicopter routes themselves were most likely adapted with few, if any, significant alterations.

One reason why I believe the helicopter routes were either copied directly from the military chart, or were otherwise designed mainly to accommodate the needs of the Department of Defense, is that Route 1, the route to Greenbelt requested by the incident helicopter pilot and the only special military route specifically discussed in the NTSB report on the 1985 incident, still leads to Greenbelt today.[27]

Another reason is that the US military was by far the largest helicopter operator in the DC area at the time and still is today, accounting for 79.2% of all helicopter traffic using helicopter routes within 5 nautical miles of DCA.[1:200] This is largely because civilian and law enforcement operators mostly don’t fly from a fixed point A to a fixed point B. Police and news helicopters tend to circle for long periods in a particular area in order to follow an event on the ground, and medevac helicopters have to fly to wherever the patient happens to be, which is usually nowhere near the handful of published helicopter routes. Military helicopters, on the other hand, are there to fulfill specific missions, requiring them to fly between the same points over and over again.[3–3:08:00] As a result, the FAA added “police zones” to the chart, allowing law enforcement and civilian helicopters to circle inside a particular area with defined boundaries that can keep them separate from helicopters that might be circling in other zones. These zones deliberately avoided overlapping with some of the major helicopter routes, emphasizing the distinct operating models they were designed to accommodate.[27] Therefore, there would have been few stakeholders in the helicopter route design other than the US military.

The identity of the organization that first drew the helicopter routes — and I do believe it was the Department of Defense — is important because it helps explain some of the glaring shortfalls in the route design. But before I discuss those problems, we need to look at what exactly a helicopter route is, in the legal sense.

Each helicopter route is depicted on the chart as a wide blue line that typically follows a visually distinctive route, such as a river or a highway or a chain of specified landmarks. Although the blue lines bear some resemblance to a corridor of airspace, they’re purely illustrative, because the routes don’t actually have defined lateral boundaries. For example, the pre-accident route chart stated that Route 4 should be flown “via the east bank of the Potomac River,” but nowhere did it say how close to the east bank one needed to be, nor was any similar information provided for any other route either.[1:46] The routes did include specified altitudes, although the chart contained contradictory information. An info box labeled “recommended route altitudes” stated that an altitude with a line under it was a minimum, an altitude with a line over it was a maximum, and an altitude with both lines was “recommended,” while a separate info box said “all altitudes are maximum,” leaving it unclear whether any altitudes were recommended or mandatory.[1:45]

FAA personnel testified at the NTSB hearings that the helicopter routes, in and of themselves, carry no regulatory force. Therefore, all minimum and maximum altitudes were in fact “recommended” and the only way to decide whether a helicopter was too far from the route centerline was personal judgment. In the FAA’s view, the purpose of the routes was to provide named paths that could be referenced to facilitate communication between pilots and air traffic control. The idea was that instead of saying “I want to fly to point B via points C, D, E, F, and G,” a pilot could just ask “I want to fly to point B via Route 3,” and the controller would clear as requested, with a mutual understanding of where the helicopter would go.[1:42:43] An unapproved deviation from the route would constitute a violation of an ATC clearance, but not a violation of the route itself, because the routes are non-regulatory and cannot strictly speaking be “violated.”[3–7:02:30]

Several of these helicopter routes passed in close proximity to DCA. Route 1 came within approximately 1 kilometer of the northeast side of the airfield at its closest approach before angling away up the Anacostia River, with a maximum altitude decreasing from 1,300 feet at Cabin John to 200 feet east of the Arlington Memorial Bridge. Route 6 crossed directly overhead the center of the airport from west to east with a recommended altitude of 1,500 feet, well away from any departing or arriving aircraft. And most importantly for this story, Route 4 branched off of Route 1 at Hains Point, located at the confluence of the Anacostia and the Potomac Rivers opposite DCA, and then proceeded south down the east bank of the Potomac past the Woodrow Wilson Bridge, paralleling the runway 1 approach corridor at a maximum altitude of 200 feet. The centerlines of Routes 1 and 4 crossed the approach corridors for runways 19 and 33 at distances of approximately 2.3 and 1.1 kilometers from the runway thresholds, respectively.[1:44]

Incredibly, the proximity to the approach corridors into DCA did not appear to have been considered in the design of the helicopter routes. Although the greatly reduced route altitudes in the areas near the airport gave the impression that the 200 foot maximum was intended to vertically separate helicopters from DCA-bound aircraft, no such separation actually existed. In fact, a helicopter traversing Route 4 along the eastern shore of the Potomac River at the maximum altitude of 200 feet would pass just 75 feet below the optimal 3-degree glide path into runway 33. Away from the shore, this margin further reduces toward zero at a rate proportional to one’s charitableness in interpreting the location of the route’s undefined western boundary.[1:207–208]

FAA personnel explained that the helicopter routes were never intended to provide separation from fixed-wing traffic approaching DCA or any other airport, and for good reason. In order to guarantee separation for a helicopter flying inside the route, it would need to be an instrument flight rules or IFR route, defined with respect to GPS coordinates and navigational aids. But helicopters mostly fly under visual flight rules with respect to landmarks, so an IFR route would be useless to virtually all helicopter operators.[26] The helicopter chart therefore included only VFR routes, but a VFR route that relies on a pilot’s judgment of their distance from landmarks rather than the readings of instruments inherently cannot have strictly enforceable boundaries, which in turn means it is fundamentally incapable of guaranteeing separation from traffic on other routes.

Considering these facts, it remains unclear why exactly the maximum altitude on routes 1 and 4 decreased to 200 feet in the area of National Airport. The low maximum altitude might have been a mitigating measure intended to reduce the likelihood that helicopters would pass directly through the approach and departure corridors for runways 1/19 and 15/33 without technically guaranteeing anything, but if so, it was at best ineffective and at worst actively misleading. The only remotely effective solutions would have been to establish a very high minimum altitude, far above any landing airplanes, or even better, to give DCA a wide berth and avoid establishing helicopter routes so near to the runways in the first place. But remember, the helicopter routes weren’t created by the FAA — they were created by the Department of Defense. And as we will see in Chapter 5, the DoD didn’t care very much about the impact of their mission on civilian air traffic. They wanted a low altitude route down the Potomac River past DCA, so they got one.

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Before getting any deeper into the weeds surrounding helicopter Route 4, I want to make sure everyone understands what I mean when I say “separation.”

Separation is, obviously, the art of keeping airplanes from running into each other. Within controlled airspace there are several layers of separation, but the most fundamental layer in all airspace is visual separation — the expectation that pilots will see and avoid each other. Pilots scan for traffic continuously when flying in visual meteorological conditions in order to identify potential threats, while air traffic controllers use radar to identify traffic and call out its position so pilots know where to look. That’s what we call pilot-applied visual separation, but there is also tower-applied visual separation, which is when the controller sees two aircraft with their own eyes and provides instructions as required to avoid a conflict. In either case, the minimum separation distance under visual separation is left to the judgment of the pilot or the controller, or a company or tower policy if there is one.[1:71]

In radar-controlled airspace, the next layer above visual separation is radar separation. This type is fairly self-explanatory: the controller sees the aircraft on their radar screen and issues maneuvering instructions as needed to assure separation. The minimum radar separation between an instrument flight rules (IFR) aircraft (such as an airliner) and a VFR aircraft (such as a helicopter) in Class B airspace is 1.5 nautical miles laterally and/or 500 feet vertically.

Finally, the highest and most effective layer is procedural separation, referring to the use of standard procedures and published routes that minimize the risk of traffic conflicts arising in the first place. Procedural separation has many forms, but some common examples include the use of approach procedures that separate traffic bound for adjacent airports or the use of odd or even numbered altitudes on upper level airways depending on the direction of travel. The standard procedural separation distance is 1,000 feet vertically, while the minimum lateral distance is situational and beyond the scope of this article.[29]

At National Airport, helicopter routes were not technically procedurally separated from any of the approach corridors because of their lack of defined boundaries. However, for all practical purposes, a rudimentary form of procedural separation existed from runways 1 and 19 because the centerlines of Routes 1 and 4 paralleled the approach/departure paths for those runways instead of directly crossing them. Although the required procedural separation minima were not met, a collision was relatively less likely at those locations because it would have required a fairly large lateral and vertical deviation by one of the aircraft. On the other hand, Route 4 cut directly across the approach corridor into runway 33 at almost exactly the same altitude as the optimal glide path, creating an extremely high collision risk if a helicopter and an airplane were to cross the intersection at the same time. If the helicopter was just a few tens of feet above the maximum route altitude, or if the helicopter was a 100 or 200 meters west of the route centerline, or if the airplane was slightly below the optimal 3-degree glide path, or some disadvantageous combination of all three, then a collision was virtually certain.

Most controllers at the DCA tower were aware that Route 4 was not procedurally separated from runway 33,[1:52] and it was the normal practice to use radar or visual separation in this area instead. This meant either instructing helicopters to hold at Hains Point or the Wilson Bridge while an aircraft landed on runway 33, or approving pilot-applied visual separation if the helicopter pilot reported the landing aircraft in sight. Furthermore, because radar separation minima between helicopters on Routes 1 and 4 and aircraft on runways 1 and 19 were also not met, visual separation had to be applied in these areas as well. The need to apply these forms of separation every time a helicopter flew near the airport significantly increased controller workload relative to a hypothetical route system that didn’t conflict with the runways.[1:252] I’ll go into more detail about how exactly controllers coped with this in Chapter 4, but for now it suffices to say that this was a capital-P Problem, and everyone on the ground knew it. So what was to be done?

According to the agency’s own regulations, the FAA was supposed to conduct an annual review of all helicopter route charts in order to identify areas for improvement. The issues I just described ought to have been priority number one. However, the FAA could produce no documentation of any such reviews, and the NTSB concluded that the required reviews were most likely never performed.[1:264] A crucial opportunity to escalate the controllers’ urgent concerns was therefore missed.

Then, on the 24th of May 2013, disaster very nearly struck. That afternoon, a Republic Airways ERJ inbound from Columbus, Ohio was approaching runway 33 while a military helicopter entered Route 4. The pilot of the helicopter reported the traffic in sight, and visual separation was approved. But instead of holding short and waiting for the airliner to pass, the helicopter kept flying right toward it. The controller asked repeatedly whether the pilot actually had the ERJ in sight, but confusion prevailed. At the last moment, with the helicopter located just 950 feet laterally from their aircraft and at the same altitude, the Republic pilots spotted it and executed a go-around, avoiding a mid-air collision. The incident occurred in broad daylight.[26][30]

For the controllers at DCA, the near miss had been entirely predictable, and many were tired of waiting around for something to change. As a direct result of the incident, controllers founded an informal helicopter working group, whose mission was to address concerns about helicopter operations near DCA and perform outreach to helicopter operators.[1:279] The group’s first proposal was to move Route 4 to the east, over interstate 295, so that it would no longer directly intersect with the runway 33 circling approach course.[1:48] Radar separation minima of 500 ft vertically or 1.5 nautical miles laterally would still not be met, but due to the greater height difference between helicopters and airplanes in this area, the collision risk would be substantially reduced.

Sometime after the 2013 incident, this proposal appears to have been advanced out of the facility by the Air Traffic Manager (ATM), but nobody interviewed by the NTSB knew exactly how far it got. Some said it might have made it as far as the Pentagon[63:814] on the military side and “beyond the district level” on the FAA side,[63:729–730] but somewhere up there in the upper levels of the bureaucracy, the proposal quietly died. In an NTSB interview after the accident, one participant stated that the working group was told their proposal had been rejected because the Department of Defense considered Route 4 to be important to continuity of government operations.[1:48][63:805] The nature of those operations will be discussed in Chapter 5.

Following the failure of their years-long efforts to move Route 4, in 2022 the helicopter working group resorted to Plan B, which was to ensure that helicopter pilots were informed about the collision risk in this area so that they could, if nothing else, exercise increased vigilance. Their new proposal was to add language to the helicopter route chart highlighting the intersection of Route 4 and the runway 33 approach path, as well as two other locations, as collision risk “hotspots.” But when the proposal was escalated to the FAA’s chart office, the office rejected the inclusion of the hotspots because under the agency’s VFR chart specifications, the term “hotspot” refers to an area of increased ground collision risk, and there was no provision for including airborne collision hotspots.[1:49–50]

During the NTSB’s public hearings on the accident, board member Todd Inman asked the head of the chart office why the proposal was rejected at DCA when the Los Angeles VFR helicopter route chart contained labels reading “caution, intense helicopter traffic,” as well as special procedures for navigating through the high-traffic areas. The head of charting replied that the helicopter working group had not asked for such labels; they had asked for “hotspots.” She did not have a good answer for why language similar to the Los Angeles chart was not proposed as an alternative. NTSB Chairwoman Jennifer Homendy subsequently excoriated the FAA witnesses for stalling the safety improvement process with pedantic nonsense, shouting, “Are you kidding!? Sixty-seven people are dead!”[3–6:34:00]

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In the end, despite years of warnings from air traffic personnel, nothing was done to mitigate the collision risk along helicopter Route 4.

In the meantime, helicopter operators did what they could to mitigate the risk themselves. One pilot at a medevac company testified to the NTSB that his company’s pilots were forbidden from using Route 4 at all, following a 2017 near mid-air collision with a US Army Blackhawk helicopter that was traveling along the route and did not appear on their traffic displays. The company also enforced a minimum altitude of 500 feet at night, effectively banning portions of Route 1 after dark.[3–3:12:40] The US Coast Guard also discouraged its pilots from using Routes 1 and 4 between the Memorial Bridge and the Wilson Bridge when there was heavy commercial traffic at DCA.[1:54] But traffic on helicopter route 4 remained heavy because other military branches continued to use it at all times of day and without regard for commercial flight schedules. And at the DCA control tower, the air traffic controllers did what they could to keep traffic flowing, even as unsolved problems kept piling onto their shoulders, growing heavier with each passing year.

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Chapter 4: Making It Work

No matter how many airplanes and helicopters are crammed into the airspace above Washington, it’s the responsibility of the DCA tower to figure out how to get them all to their destinations while maintaining safe separation between them. With National Airport’s uniquely complex operations, the tower has to be on top of its game. That’s not to say that any tower can afford otherwise; rather, that at DCA the game is especially intense. But was the tower properly equipped to handle its mission in the safest way possible? There is good cause to doubt that they were, and this Chapter will dive into the reasons why.

The DCA tower is responsible for all low-level traffic at the airport or in its vicinity, including the entirety of the District of Columbia as well as surrounding areas of Maryland and northern Virginia within a radius of 15 nautical miles (28 km), except where this radius overlaps with airspace controlled from other airports, such as Dulles. This airspace contains or lies within a number of nesting restricted zones, including the 30-nautical-mile Washington Special Flight Rules Area, where all aircraft must remain in contact with air traffic control; the Flight Restricted Zone, extending up to 15 nautical miles from DCA, where only government aircraft, police, and DCA-bound commercial airliners are allowed, with narrow exceptions; the DCA Class B airspace, where all aircraft must be equipped with certain radio or GPS navigation equipment and ADS-B Out capability (I’ll explain that later in this Chapter); and the P-56A, P-56B, and P-73 prohibited areas, which surround the White House, Capitol Building, and National Mall; the US Naval Observatory; and the Mount Vernon plantation, the historic home of George Washington, respectively.[27][31] Entry into the latter will earn a citation; entry into P-56A may result in your aircraft being shot down by a surface-to-air missile, depending on how threatening your trajectory looks, although the details are obviously shrouded in some level of secrecy.

The P-56A prohibited area lies less than 3 kilometers directly beyond the departure end of runway 1, forcing departures from this runway to turn left immediately after takeoff to climb out along the Potomac River to the northwest. Similarly, aircraft arriving on runway 19 must approach down the Potomac at an oblique angle before making a right turn at the last moment to align with the runway.

Altogether, this matryoshka of restricted and prohibited areas, combined with its heavy and varied traffic and small geographic area, makes Washington one of the most complex airspaces in the world. Across the capital area, several towers at major airports like Dulles and Andrews Air Force Base share the load, as well as the Potomac TRACON, which is responsible for mid-level airspace over the entire region, stretching down to ground level in areas more than 15 nautical miles away from a major tower. At higher levels, the Washington Air Route Traffic Control Center, or ARTCC, handles en route traffic. But the center of it all is the DCA tower, with its commanding view out across the Potomac River and into America’s seat of power.

At the time of the accident, the FAA’s authorized staffing for the DCA tower included 28 air traffic controllers and 6 supervisors, while the actual staffing levels consisted of 25 controllers and 4 supervisors.[1:58–59] Compared to most facilities across the nation, this was a relatively minor shortfall, and in fact, broadly speaking, the national air traffic controller shortage that has made headlines repeatedly over the past several years had little or nothing to do with this accident. This is because the number of personnel on duty in the tower at the time of the collision was more than sufficient to staff all the required positions,[1:222] a fact that I’ll revisit in more detail in Chapter 7. Nevertheless, every controller interviewed by the NTSB was concerned about tower staffing levels, and DCA tower operations manager Clark Allen testified at the NTSB hearings that the staffing total itself was misleading, explaining that the figure of 25 controllers and 4 supervisors didn’t account for any who might be on leave or sick or otherwise unavailable. To staff all required positions across all three shifts for one day, 20 controllers were needed, but on a given day, the number actually available was quite often less than this.[4–0:53:00] The resulting shortfall would force the supervisor to combine positions, increasing controller workload. Issues of heightened controller workload nationwide due to short-staffing are well documented in the media, which is full of very real horror stories of controllers working overtime under grueling conditions with failing equipment for weeks on end. These topics are best saved for a future article, perhaps on the March 2026 runway collision at LaGuardia, but for now, just keep those thoughts on back burner.

In all, a shift at the DCA tower contains nine controller positions, some of which are usually combined at any given moment. On the front line handling takeoffs, landings, and runway movements is the Local controller, who uses the callsign “tower” on radio transmissions, despite occupying only one of several roles in the tower. An Assistant Local controller helps the Local controller with various tasks, such as watching radar displays, observing aircraft visually, and spotting developing conflicts. Unique to DCA and a small handful of other airports, a helicopter control position also exists to coordinate helicopter traffic within Washington airspace. Meanwhile, a Ground controller handles all aircraft and vehicles moving on the airport surface other than the runways, and a Clearance Delivery controller reviews flight plans, issues routing clearances prior to pushback, and creates flight strips that the other controllers can use to monitor an airplane’s progress through the airport. In the background, these roles are supported by a Flight Data position that performs data entry, completes paperwork, and performs various other miscellaneous tasks; a Traffic Management Coordinator who handles macro-level traffic flow issues within the DCA airspace; and an Air Traffic Manager, or ATM, who performs administrative tasks such as maintaining Letters of Agreement, facility directives, and standard operating procedures, among other responsibilities. All of the front line control positions are in turn overseen by an Operations Supervisor, or a designated Controller in Charge (CIC) if no supervisor is available, whose job is to monitor the other controllers, combine or de-combine positions, and make notifications of any events that need to be escalated beyond the tower.[1:59–60]

During any given shift, some of these positions were nearly always combined, meaning that one person was fulfilling both sets of duties. It was normal for one person to handle both Clearance Delivery and Flight Data, and the supervisor could, at their discretion, combine the Helicopter and Local control positions as well.[1:61] This came with a number of tradeoffs. On the one hand, assigning a single controller to handle both airborne airplanes and airborne helicopters eliminated the need to coordinate between two controllers whenever a helicopter and an airplane needed to fly in close proximity — and as you may recall, it was the failure to coordinate in this manner that led to the 1985 Eastern Air Lines near miss. Combining the positions also had the potential to increase the Local controller’s situational awareness, as long as traffic levels were low enough that the number of aircraft didn’t become overwhelming. But on the other hand, staffing the positions separately added a second set of eyes, helping anticipate and prevent conflicts earlier; and it reduced frequency congestion, because each controller would only need to monitor one frequency instead of two.[1:70] The split frequencies also created other problems when the positions were combined, because even though the controller’s outgoing transmissions were broadcast on both frequencies, airplane pilots couldn’t hear the helicopters’ responses, nor could the helicopter pilots hear the airplanes’ responses.[1:2] Pilots were instead forced to guess whether a helicopter or an airplane might be speaking based on context alone, and whenever they got it wrong, the controller would miss one of the transmissions. Nevertheless, it was impractical to use a common frequency when the positions were combined because the VFR helicopter charts only listed the helicopter frequency, and the charts used by airplanes only included the Local frequency.[3–2:40:20]

The practice of combining the Local and Helicopter positions relied on the Operations Supervisor’s awareness of the number of helicopters in the DCA airspace. If the number of helicopters was getting too high with the positions combined, the Supervisor needed to recognize this and de-combine the positions, or the Local controller needed to notify the Supervisor that the workload was getting too heavy. If neither of these things happened, then the amount of traffic could overload the Local controller, causing them to lose situational awareness. But several policies — or in some cases, their absence — hindered the Supervisor’s ability to make effective decisions about when to combine or de-combine the positions.

Supervisors were given a basic list of factors to consider when making the decision to combine the Helicopter and Local positions, but there were no specific criteria that could be used to make that determination, other than the Supervisor’s judgment of the listed factors. The Standard Operating Procedures (SOPs) for the DCA tower stated that the positions would “normally be de-combined” between 10:00 and 21:30 each day,[1:70] but this was rarely adhered to; on the day of the accident, for instance, the positions were staffed separately for a total of just one hour and 20 minutes.[4–0:58:15]

Prior to 2023, the DCA tower SOPs required the Supervisor to document the reason for merging the positions, which presented a barrier against habitually combining them without a proper evaluation. However, in 2023 this requirement was removed, which likely helped normalize keeping the positions combined for long periods without evaluating the risks.[1:282] Furthermore, while the Local controller in theory could ask for relief, the SOPs didn’t include any guidance to help controllers decide when the workload had reached the point that relief was required,[1:225] likely encouraging them to accept a higher workload than necessary out of a reluctance to ask for help.

All of these factors indicated that the Helicopter and Local control positions were probably quite often combined at times of high traffic volume when they should have been staffed separately, leading to increased workload and decreased situational awareness for the Local controller. But this was far from the biggest issue with the DCA tower’s safety culture.

In 2022, a retired FAA ATC specialist was hired as a consultant to perform a routine external compliance review (ECV) of the DCA tower. He could not possibly have been prepared for what he found. On the first day of the ECV, his team identified no less than 33 non-compliant items, some of them significant, the most he could ever recall seeing — so many, in fact, that he decided to pause the review in order to get the tower immediate help instead. His team ended up working with DCA for about 9 months, during which time he identified broad issues including a lack of staff support; poor communication between the tower and the Potomac TRACON; skipped paperwork; “pervasive shortcutting of standard phraseology;” helicopters flying in close proximity to airplanes, including underneath approach corridors; and failures to issue required traffic advisories to aircraft in close proximity to one another.[1:80–81]

In interviews with the NTSB, a quality control specialist who worked at the DCA tower between 2018 and 2022 stated that she also identified widespread deficiencies related to non-use of standard terminology, failure to issue traffic advisories, and improper use of pilot-applied visual separation between helicopters and airplanes. Reportable loss of separation events, in which the distance between aircraft fell well below the radar separation minima, were common and usually went unreported. In fact, she said that management avoided filing such reports because it would make the facility “look bad.”[1:187–188] She believed this was most likely because the managers were worried about securing promotions.[32]

Her 20-page interview summary plays like a horror show of violations. For example, Supervisors almost never intervened to correct improper behavior by controllers — even serious ones, like controllers using their cell phones while on duty. Additionally, FAA rules require 6,000 feet of separation between departures, and for the first departure to be airborne, before the second is cleared for takeoff — but controllers frequently ignored this rule and cleared the next departure for takeoff as soon as the previous one started rolling. Controllers also regularly cleared flights for takeoff while an arrival was less than 2 nautical miles from the runway in instrument meteorological conditions, which is not allowed. Both of these actions resulted in reportable losses of separation, but facility managers told her to report the events verbally to them instead of recording them in writing. When she continued to report the events, the Air Traffic Manager at the time told her to “stop finding losses of separation.”[32]

ATC union representatives were equally unhelpful, as she recalled being told, regarding loss of separation events, that the events were “[no] big deal” because “they weren’t going to hit.” Later when she informed a union representative that DCA had not met its improvement targets for loss of separation events, they told her to “just lower the target.”[32]

The scope of the issues that she identified went beyond isolated discrepancies; in her interview, she stated that what she saw was a “widespread acceptance of non-compliance with applicable rules, regulations, orders and directives.” Her discussions with colleagues led her to believe that these issues existed not only at the DCA tower, but throughout the entire National Airspace System. Nevertheless, because her job was to help improve the quality of operations at DCA, she escalated each non-compliance through the processes that were available to her. But facility management regularly interfered with her work, overruling her to mark items as compliant and retaliating against her when she complained. For instance, when a controller failed to issue a required safety alert to an aircraft involved in a traffic conflict, the tower procedure was to give the controller a safety briefing to reiterate the rules, but in her experience the briefings were ineffective because the issue was systemic, not individual. When she told management that the issue needed to be resolved on a higher level, they accused her of insubordination and told her to “be quiet” and just hold the briefings. She said management then reported her for “unprofessional conduct,” after which, in 2022, she voluntarily left the facility.[32]

In her view, the DCA tower suffered from a lack of interest in the rules. She described the normalization of deviance at the facility as a “graveyard spiral” in which a lack of enforcement against non-compliances enabled their further spread, with each new generation of controllers receiving training from instructors who were themselves improperly trained, resulting in not only widespread violations, but also outright ignorance of what the rules even were. And then, after some years, these same controllers would be promoted into management, perpetuating the cycle.[32]

In fact, a high rate of personnel turnover was another serious problem affecting the facility. Investigators believed that this issue was linked to a facility downgrade that occurred in 2018.

All FAA air traffic facilities, including towers, TRACONs, and centers, are assigned a “facility level” on a scale of 4 to 12, with 4 being the lowest traffic volume with the least complexity, and 12 being the highest traffic volume and most complexity. The facility level is a determining factor in controller compensation.

Prior to 2018, DCA was a level 10 facility, indicating high traffic volume and complexity with correspondingly high controller pay. However, in 2016 the FAA’s National Validation Team started counting helicopters assigned a transponder code by the Potomac TRACON as belonging to that facility only, even if they later entered DCA airspace, resulting in a 70% decrease in VFR helicopter traffic counting toward DCA’s facility level. As a result, in 2018 the Potomac TRACON was upgraded from level 11 to level 12, while DCA was downgraded from level 10 to level 9, resulting in a pay cut for all DCA tower staff, even though the amount of traffic had not actually changed.

When the NTSB asked the FAA to provide documentation of the criteria it used to downgrade the facility level, the agency refused to hand anything over,[1:91] claiming unilaterally that this matter was outside the scope of the NTSB’s investigation.

The downgrade caused experienced controllers to leave the facility and made it hard to retain new ones, because the pay was no longer commensurate with the high workload or the high cost of living in the Washington area. Furthermore, controllers looking to upgrade from a level 8 to a level 9 facility avoided DCA in favor of facilities with a lower workload, while those who did work at DCA looked to upgrade quickly to a level 10 facility where the workload might not be much lighter but the compensation would be better.[1:89–92]

Ever since the downgrade, the DCA tower had been constantly training up new controllers only to lose them as fast as they came. The relatively low pay, high workload, and rapid turnover had a significant negative effect on facility morale,[1:91] which could not have been helped by the tower management’s operating style. But management themselves also suffered from high turnover for the same reasons as the controllers. The former quality control specialist said that some management personnel only lasted a few months before seeking promotions, some positions remained vacant for long periods, and at one point the ATM was reassigned due to an FAA investigation into fraudulent employee position and time records.[32]

In their final report, the NTSB wrote that these serious allegations from multiple individuals “all suggest an organization that does not embrace the principles of open communication, just culture, and continuous improvement inherent to a positive safety culture.”[1:284] It’s relatively rare for an NTSB report to describe an organization in such terms, but after reading the firsthand accounts of people who worked there, the conclusion is inescapable.

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Laboring under disinterested management with a deficient safety culture and faced with excessive fixed-wing traffic and a constant flow of helicopters ducking over, under, and through the congested approach paths, DCA controllers found that when it came to performing their work both safely and efficiently, the odds were stacked against them. And yet in almost every interview with the NTSB, controllers and management alike told the NTSB that the directive from the top was to “make it work.”[1:78] “It can be taxing on a person…constantly having to give, give, or push, push, push in order to efficiently move traffic,” the tower Operations Manager said. “Whenever the controllers at DCA just make it work, they are going above and beyond to approach the limit of the rules and regulations. They’re pushing the limits of what can be done to safely and efficiently move the aircraft and/or helicopters at DCA…you’re pushing the line.”[1:253]

With that in mind, let’s take a look at how, exactly, the DCA tower (and to a lesser extent the Potomac TRACON) “made it work.”

One of the most constantly challenging tasks faced by both facilities was the need to space arrivals sufficiently far apart to allow departures to occur from the same runway. Arrival spacing, which controllers call “miles in trail,” must take into account the relative speeds of the two aircraft, as well as the time required for the leading aircraft to taxi off the runway, and for a departing aircraft to enter the runway and become airborne, before the next arrival touches down. As I discussed in Chapter 2, this was an inherently tricky issue whenever actual traffic numbers approached the maximum arrival rate, because the arrival rate had been set too high.

In practice, controllers stated that they needed at least four nautical miles in trail between arrivals in order to squeeze out a departure.[1:75] At a speed of 142 knots, the FAA’s reference approach speed for a Boeing 737 NG, an aircraft will cover that distance in approximately 101 seconds.[33] As you may recall, that’s almost exactly equal to the 100-second average interval between arrivals during an hour with the maximum arrival rate of 36 for runway 1, before accounting for aircraft that circle to land on runway 33 instead. So, sanity check passed.

But again, as I said in Chapter 2, the real world isn’t perfect. Getting at least four miles in trail between every arrival is hard because airplanes approach at different speeds and they join the queue at different points. And if the number of miles in trail is exactly four, then, as I said before, any delay by the departing aircraft could still lead to a loss of separation with the next arrival, potentially causing that arrival to go around — an event that has to be reported. Controllers try to avoid such events by issuing instructions like “cleared for immediate takeoff,” but it doesn’t always work.

Because the DCA tower only controls aircraft already on final approach, achieving the required miles in trail falls mostly on the shoulders of the Potomac TRACON. Data acquired by the NTSB shows that when the tower requested at least four miles in trail, the TRACON successfully provided that spacing at the point of handover 90% of the time. However, in many cases these aircraft had not yet slowed down to their final approach speed by the handover point, causing them to catch up with slower aircraft ahead before reaching the runway. As a result, only 60% of arrivals still had at least four miles in trail by the time they arrived over the runway threshold. In practice, five miles in trail were needed at the handover point to compensate for this.[1:76]

The letter of agreement between the DCA tower and the Potomac TRACON stated that the number of miles in trail should be agreed on a rolling basis.[1:75] A fixed miles-in-trail agreement was not included because the two facilities couldn’t agree on a number.[4–2:36:50] At the NTSB hearings, Nick Fuller of the FAA Air Traffic Organization (ATO — the department that oversees air traffic control) stated that it wasn’t the TRACON’s job to anticipate how spacing between aircraft will change after the handover point to the tower, so if the tower needed more spacing, they would need to explicitly ask for five miles in trail.[4–2:47:20] But achieving this number was difficult for the TRACON as well. In order to achieve four miles, let alone five, TRACON controllers sometimes had to resort to what they described as “nonstandard” techniques, such as giving aircraft complex delay vectors, assigning slower than normal speeds, or sending aircraft out away from the airport for some distance before turning them back in again to rejoin the queue, a method colloquially known as “tromboning.” But even with these techniques, there was only so much the TRACON could do with their own rather limited and congested airspace, especially when they often themselves received insufficient miles in trail from the Washington ARTCC, via no less than five separate “feed” corridors that they had to integrate into an orderly queue.[1:75]

I’m under no illusion that these challenges exist only in Washington; in fact, from everything I’ve heard, they’re simply part of the TRACON job description, and every such facility faces them to some degree. But it seems that the Mount Vernon Area of the Potomac TRACON was affected to an unusual extent, given that it was this facility that originated the 2023 request to lower the DCA arrival rates, before even the tower itself.

Whenever the tower received less than the requested miles in trail, their most effective option to correct the spacing was to divert aircraft to runway 33. And that meant a higher workload for pilots and a more complex overall traffic situation — not to mention routing airliner traffic through that nasty intersection with Helicopter Route 4.

A technology that could mitigate these spacing issues in fact already exists. Known as time-based flow management, or TBFM, the system calculates when each aircraft will arrive over a certain point, removing much of the human guesswork from the assembly of the arrival queue.[1:79] Had TBFM been in use at the Potomac TRACON, the facility would have been able to achieve the requested miles in trail much more often.

A TBFM system had actually been present at the Potomac TRACON for more than ten years, but by the time of the accident, it still had not been turned on.[1:79] In testimony at the NTSB hearings, Bryan Lehman, the Potomac TRACON ATM, stated that they couldn’t use the system until the New York and Washington ARTCCs, from which the TRACON received inbound aircraft, also installed it. However, that never happened.[4–7:23:15] At the NTSB hearing, when asked whether the arrival rate would have to be reassessed for TBFM to be “successful,” Ms. Chendi from the FAA’s Washington District answered “yes.”[4–3:44:50] However, she also stated that she didn’t know the reason why TBFM was not activated.[1:79] So was the arrival rate too high for TBFM to work? Did this fact contribute to the failure to activate the system for over 10 years? Nothing in the NTSB evidence docket, at least that I was able to find, provides a clear answer to this question.

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The failure to activate TBFM perpetuated the need to divert aircraft onto runway 33 and thus through the known collision risk area along Helicopter Route 4. Even with TBFM this most likely would have continued, but it would have reduced the number of aircraft exposed to the risk.

Regardless, controllers were aware that the risk area existed, and the tower had developed various practices for separating airplanes from helicopters in that area. As I discussed in Chapter 3, a helicopter transiting Route 4 and an airplane approaching runway 33 had a very high risk of collision if they were to cross paths at the same time. If no effort had been made to keep helicopters from crossing the approach path while an airplane was inbound to runway 33, the airspace configuration probably wouldn’t have lasted a month without a crash. Instead, it lasted at least 39 years because the controllers’ techniques generally worked — albeit not well enough in the end.

I already explained in Chapter 3 that radar separation could be applied to Route 4 by instructing a southbound helicopter to hold at Hains Point or a northbound helicopter to hold at the Wilson Bridge until the inbound aircraft has landed on runway 33. Some helicopter pilots even offered to hold voluntarily if they knew a runway 33 approach was occurring.[1:72] However, while this technique was used when convenient, the DCA tower Operations Manager Clark Allen testified that it increased controller workload because the resulting holding pattern would pass very close to numerous helipads and the airport itself, requiring constant monitoring to ensure that radar separation minima were maintained.[4–3:42:30] Holding a helicopter farther out on Route 1 where radar separation was less complicated would be ineffective because controllers usually didn’t know whether a helicopter would conflict with a runway 33 approach until it got to Hains Point.

Instead, most of the time controllers relied on pilot-applied visual separation. The way this worked was typically as follows.

First, the controller would advise the helicopter pilot about an airplane, ideally including as much information as possible. FAA regulations require a traffic advisory to include the traffic’s azimuth (usually in the form of a clock position), distance, relative direction of travel, and altitude and aircraft type if known. If all of this information is included and conditions are clear, the pilot should spot the traffic relatively quickly. If the pilot reports the traffic in sight and requests visual separation, the controller will state “visual separation approved.” The tower can also instruct the pilot to “maintain visual separation” in the absence of a request, after which it’s still up to the pilot to visually maneuver around the traffic in a safe manner.[1:71, 83–84]

Accurate traffic information is crucial to pilot-applied visual separation because a complete traffic advisory has been shown to increase the effectiveness of a pilot’s traffic scan by a factor of eight. The probability of spotting an aircraft on a collision course without information about the traffic’s azimuth and distance is relatively low until just before impact due to the limitations of human visual perception.[1:141] Traffic advisories are also more effective if they are also issued to the aircraft that is being separated from, not just the aircraft that is doing the separating. However, this is not required unless their radar targets appear likely to merge.[1:85, 231]

Unfortunately, incomplete traffic advisories were commonplace at DCA, according to both the former quality control specialist[1:187] and the tower communications on the day of the accident. Evidently the required phraseology was not being enforced.

Nevertheless, Clark Allen testified that the use of visual separation between helicopters and airplanes was “’paramount’ to operating efficiently given the volume of traffic and complexity of the DCA airspace.”[1:71–72] This was because maintaining Class B radar separation minima of 1.5 nautical miles laterally and 500 feet vertically, with DCA’s airspace configuration, would result in a high rate of holds, delays, and go-arounds that the NTSB wrote would only “[further] increase controller workload and contribute to additional airspace congestion and traffic complexity.”[1:252]

The centrality of this fact to the accident narrative cannot be overstated. It was the volume of traffic combined with the complexity of the airspace that made visual separation operationally necessary. That’s the whole reason anything I said in Chapters 2 and 3 is important. In some of the most tightly controlled airspace in the world, with all the technology available to pilots and controllers alike, the tower still relied on pilots seeing and avoiding each other using little more than the Mark One Eyeball because it was the only way to efficiently meet the demands imposed them.

Controllers and pilots alike generally understood that this was the case and did whatever they could to make visual separation work — even if it meant bending or breaking the rules. For example, an external compliance review in November 2024 discovered that controllers were sometimes advising airplanes that a helicopter had them in sight and was maintaining visual separation, even though the helicopter had not in fact reported the aircraft in sight yet; the controllers simply anticipated that it would.[1:252] At the same time, some pilots developed a habit of declaring “traffic in sight” without actually seeing the traffic because they thought they knew where the traffic would be, or anticipated that they’d catch sight of it soon. A standardization (instructor) pilot with the US Army stated that this was especially common while flying parallel to airliner traffic using runways 1 and 19 because he knew he would not be on a converging course with the traffic. “I know where I’m at. I know where the traffic is, and I know it’s not a factor,” he said. “So, I will say visual separation, and I’ll have the traffic [in sight] 15 to 20 seconds later. …I know if I don’t say it [traffic in sight], I may have to hold.”[1:72] Controllers were mostly unaware that pilots were doing this, causing them to systematically overestimate helicopter pilots’ level of traffic awareness.[1:254]

Because of these practices, as well as the inherent limitations of human visual acuity, close proximity events between helicopters and airplanes were commonplace. I’ll discuss the frequency of these events and the data that was collected about them in Chapter 6. Right now what’s important to understand about these events is that the application of visual separation doesn’t relieve a controller of the duty to intervene when aircraft are operating in unsafe proximity. The former quality control specialist who was forced out in 2022 stated that many controllers at DCA appeared not to realize that this was the case.[32]

FAA regulations hold that the highest duty priority for every controller is to separate aircraft, issuing safety alerts as required to prevent a collision if an unsafe situation exists.[1:82] A pilot reporting the traffic in sight means nothing if the aircraft are still on a collision course, so a safety alert still has to be issued. The safety alert should include the location of the conflicting traffic and, if feasible, a suggested alternate action — such as “go around” or “turn right” — followed by the word “immediately.”[1:87] If you recall, the former quality control specialist found that failure to issue required safety alerts was systemic at the facility.[32]

The fact that controllers might not have fully understood this fundamental responsibility could be an indictment of the training process, but it’s more likely that the DCA operating environment led to a normalization of deviance among controllers who theoretically knew better. Since visual separation was being employed at a rate far above that of other airports[26] specifically in order to reduce the workload otherwise associated with enforcing class B radar separation minima, there was an incentive to treat the technique as though it absolved the controller of some or all need to exercise positive control over the aircraft involved. After all, under visual separation the minimum proximity between aircraft is left to the pilot’s judgment, so if the controller still has to monitor the aircraft to make sure they don’t get “too close,” then what’s the point of using visual separation at all, from a controller workload standpoint? And therein lies the main pitfall of relying on visual separation for workload reduction: it works best if you do it wrong.

In its final report, the NTSB wrote that “The longstanding practice of relying on pilot-applied visual separation (see-and-avoid) as the principal means of separating helicopter and fixed-wing traffic in the Washington, DC area … led to a drift in operating practices among controllers and helicopter crews that increased the likelihood of a midair collision.” And so a few more strands of the web were woven together.

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In the event that all forms of separation fail to prevent a conflict from arising, the last line of defense is made up of collision warning systems, including the conflict alert system in the control tower; the traffic collision avoidance systems (TCAS) installed on all airliners; and the Automatic Dependent Surveillance-Broadcast (ADS-B) systems more typically used on light aircraft and helicopters. Before concluding this Chapter, I want to discuss each of these systems and their vulnerabilities with respect to the traffic conflict scenarios that were common at DCA.

The DCA tower was equipped with a conflict alerting system that generated audio and visual warnings based on multiple algorithms, only some of which took into account the projected flight paths of the aircraft involved. A conflict alert could be generated based on a prediction that the flight paths of two aircraft would cross, or based on proximity alone, even if the aircraft were on diverging or parallel courses. The presentation of the alert was the same in either case — a series of aural chimes and a flashing “CA” symbol on the radar display next to the data blocks for the aircraft involved.[1:85–86]

The purpose of the system was to draw the controller’s attention to a potential conflict with sufficient time to evaluate its severity and take corrective action if necessary. Nevertheless, the fact that the severity of a conflict alert could range from “no danger at all” to “imminent collision” placed a significant interpretive burden on the controller, increasing workload relative to a hypothetical alerting system that could make that evaluation itself and adjust the level of the warning accordingly.[1:259]

A 2007 study of conflict alerting systems of the type installed at DCA found that 44% of alerts don’t result in any controller action because they’re very brief or resolve themselves with no input (for example, two aircraft in close proximity but on diverging courses). Of the remaining 56%, more than two thirds sounded only after the controller had already taken action to avert the conflict, resulting in a total nuisance alert rate of 81–87%. The high rate of useless alerts and the system’s lack of discretion in issuing them desensitizes controllers to the warnings.[1:258–259] This was especially true at DCA, where the tightly packed airspace, overlapping flight paths, and frequent use of visual separation generated a constant flood of conflict alerts. An average day featured dozens of them, and in fact on January 29th, 2025 there were no less than 5 separate alerts just in the 30 minutes leading up to the accident.[1:86–87] With such a high alert rate there can be little doubt that controllers considered conflict alerts to be a normal, if annoying, side effect of the airspace configuration.

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In terms of capabilities, the traffic collision avoidance systems (TCAS) installed on all airliners are far superior to those in the tower. TCAS interrogates the transponders of nearby aircraft and determines whether they will penetrate an envelope of protected airspace around the ownship, resulting in an aural “traffic, traffic” alert if potentially unsafe proximity is projected, followed by a resolution advisory instructing evasive action if the intruder continues to approach. If both aircraft are equipped with TCAS, the two systems will communicate via the airplanes’ respective transponders to ensure that each is given opposite resolution advisories — so if one is told to climb, the other is told to descend, for instance. TCAS is capable of commanding “increase climb/descent” if the initial action is insufficient, and it will even reverse the suggested evasive action if one aircraft does not comply.

While resolution advisories are intended as a last line of defense to prevent a collision, the purpose of a “traffic, traffic” alert is to assist the pilot in visually identifying the intruder aircraft so that corrective action can be taken before the situation escalates to the point that a resolution advisory is needed. To this end, the TCAS system includes a simple updating display that depicts the location of the intruder relative to the ownship in terms of azimuth, distance, and relative altitude. (It does not however indicate the intruder’s identity or direction of movement.) Pilots should respond to a traffic alert by searching visually for the traffic, but airline SOPs, including those of PSA Airlines, stated that pilots should not take evasive action based on a traffic alert alone.[1:246]

TCAS is incredibly effective insofar as the rate of midair collisions involving airliners since its adoption has decreased nearly to zero. However, it is not completely immune to failure. For example, in 2015 a Boeing 737 collided with a BAe-125 air ambulance over Senegal, causing the latter to crash, possibly because the ambulance was broadcasting an erroneous altitude that tricked TCAS into believing the two aircraft were not on a collision course.[34] But perhaps the most glaring vulnerability of the technology — one that did not receive adequate attention prior to the disaster at DCA — is the fact that resolution advisories are inhibited below 900 feet on descent and 1,100 feet during initial climb, while aural traffic alerts are inhibited below 400 feet on descent and 600 feet during initial climb. When TCAS was originally developed in the late 1980s, these inhibit altitudes were put in place to prevent nuisance resolution advisories from being generated while operating near airports, because the system often detected a “conflict” with airplanes waiting on the ground next to the runway for takeoff clearance.[1:31] However, as early as TCAS II version 7.1, implemented in 2011, a capability was introduced to detect other airplanes’ air/ground status and inhibit any alerts if the “intruder” is on the ground.[35:28] Despite this advancement, the original inhibit altitudes were not adjusted.[1:31] Obviously there does have to be a floor somewhere, because you don’t want the system to issue a resolution advisory to descend while the airplane is too close to the ground, but significant room for improvement exists.

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The third and final type of conflict alerting system involved in this story is ADS-B. By far the newest of the three forms of conflict alerting, the technology has been partially mandatory in all US Class B airspace (such as that around DCA) since 2020 for all aircraft except military aircraft performing “sensitive government missions.”[1:267]

ADS-B consists of two components, called ADS-B Out and ADS-B In. Only ADS-B Out is currently required. Unlike TCAS, which interrogates other aircraft’s transponders, ADS-B Out passively broadcasts a host of information, including GPS position, altitude, heading, identity, ground speed, aircraft type, and more; and aircraft with ADS-B In are able to passively receive it. In fact, you can receive ADS-B Out broadcasts from aircraft in your area using a simple home receiver, which is how websites like FlightRadar24 work.

Aircraft equipped with ADS-B In can display traffic information broadcast by ADS-B Out-equipped aircraft, or aircraft equipped with mode C or S altitude-encoding transponders, on a built-in display or on an iPad equipped with an app like ForeFlight. Unlike the TCAS displays that only show a target’s position, distance, and relative altitude, aircraft with ADS-B In and a compatible traffic display can also depict the target’s direction of movement, identity, and more, all against a moving map background. This reduces workload relative to a TCAS display because the pilot doesn’t have to watch the display to determine which way the traffic is going prior to searching for it visually.[1:36] Furthermore, aircraft with ADS-B In technology can also be equipped with an ADS-B Traffic Advisory System, or ATAS, which issues aural alerts for traffic that penetrates a safety envelope surrounding the ownship. Unlike TCAS traffic alerts, which only call out “traffic, traffic,” ATAS alerts use the extra information encoded in ADS-B Out transmissions to verbally describe the traffic’s clock position, relative altitude, range, and vertical tendency, allowing the pilot to begin searching visually for the aircraft without having to look at the display at all.[1:36:37] This feature greatly reduces the workload associated with responding to a traffic alert, relative to TCAS.

However, ADS-B-based anti-collision systems are not an improvement upon TCAS because they exist in an advisory capacity only. ADS-B systems cannot issue RAs and the information they provide cannot override an air traffic control clearance.[1:37] Therefore, they lack a key layer of safety that TCAS provides, even though in other respects ADS-B is the superior traffic awareness technology.

Aircraft operating in Class B airspace, which is the only airspace class that’s relevant to this story, are required to broadcast ADS-B Out, but they are not required to have ADS-B In. All large transport category airplanes are required to have TCAS, but light aircraft are not. Therefore, while ADS-B In is extremely popular among private pilots and operators of small aircraft because it’s much less expensive than TCAS, airliners generally do not have it. ADS-B In is offered on some of the latest models, such as the Boeing 787, the Airbus A350, and the newest Airbus A320 models, and American Airlines has equipped its new A321 fleet with ADS-B traffic displays.[1:28] But older airplanes, including the CRJ-700 involved in the accident, do not have ADS-B In — and in fact there isn’t even an ADS-B In product on the market certified for installation on the CRJ.[1:37]

The NTSB has long urged the FAA to mandate ADS-B In technology in all areas where ADS-B Out is required, on the grounds that the technology is not very useful unless aircraft are equipped with both the cart and the horse, so to speak. As a result of these efforts, in 2012 Congress passed the FAA Modernization and Reform Act, which compelled the FAA to require that aircraft in congested airspace — generally assumed to be Class B airspace — be equipped with ADS-B In by 2020. In 2014 the FAA initiated a rulemaking process that would have seen ADS-B In become mandatory by 2022, but in 2018, Congress repealed this provision of the 2012 Act and directed the FAA to abandon the process.[1:215–216] As of this writing ADS-B In is still not mandatory anywhere in US airspace. However, as NTSB board member Todd Inman mentions in his statement appended to the final report, there are significant barriers to the fleetwide implementation of ADS-B In on commercial aircraft, because older cockpits weren’t designed to be compatible with currently available ADS-B displays and equipment.[1:315]

Therefore, at the time of the accident, flight 5342 was equipped with TCAS and ADS-B Out but not ADS-B In, meaning her pilots would not receive detailed traffic callouts, but could receive resolution advisories. At the same time, the US Army Blackhawk helicopter with which it collided did not have TCAS, and therefore could not receive resolution advisories, but it did have ADS-B Out and ADS-B In — although it could turn off ADS-B for “sensitive government missions,” the meaning of which was left at the discretion of the Department of Defense. I’ll get into the details of the equipment on the helicopter, and its use, in Chapter 5; and I’ll discuss how adoption of different anti-collision technologies might have affected the outcome in Chapter 9.

The most important takeaway for now is that at the site of greatest collision risk, at the intersection of the runway 33 approach path and helicopter Route 4, the expected altitude of an approaching airliner was about 275 feet, below both the 900-foot inhibit altitude for TCAS resolution advisories and the 400-foot inhibit altitude for traffic alerts. Therefore, an airplane on a collision course with a helicopter at this location would not receive a resolution advisory. So, layer that fact on top of the inherent collision risk at that location, which I’ve spent the last two Chapters elucidating, and you should be able to see the web of disaster weaving itself ever tighter.

And into this mess of excessive traffic, badly designed airspace, decaying control tower safety culture, unreliable separation practices, and flawed collision alerting systems, we must now weave yet another strand: the shambolic organization that was the US Army’s 12th Aviation Battalion.

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Chapter 5: The Rot in the Machine

If you, like me, grew up in the United States in the years immediately after 9/11, you were probably told that the US military is the greatest warfighting machine that the planet has ever seen, and maybe for a little while that was true. But if you’re a close observer of present day geopolitics and military affairs, you’ve probably noticed a marked loss of confidence in the actual capabilities of that trillion-dollar apparatus over the last five to ten years. And while this article isn’t about the decline of American power, it’s not entirely orthogonal to it either, as the following portrait of a single unit will demonstrate.

All main branches of the US military, including the Army, Air Force, Navy, Marine Corps, and Coast Guard, operate helicopters in DCA airspace, but a large majority of military helicopter traffic in the area belongs to a single unit, the 12th Aviation Battalion of the US Army. Based out of Davison Army Airfield in Fort Belvoir, Virginia, the battalion’s primary mission is to support “continuity of government” operations, specifically by transporting high-ranking military officials to safe locations in the event of a decapitation strike on the US high command. This mission has been taken especially seriously in recent decades, given that a decapitation strike was actually attempted during the September 11th attacks.

The 12th Aviation Battalion operates a fleet of 25 Sikorsky UH-60 Blackhawk utility helicopters,[1:149] supported by 400 soldiers, who are divided into six active-duty helicopter companies consisting of A, B, and C (Alpha, Bravo, and Charlie) and a Headquarters Company, as well as a maintenance company (D — Delta), the 911th Technical Rescue Engineer Company, and a rotating National Guard company. The accident helicopter belonged to B Company, which consisted of 40 soldiers.[1:160]

The battalion’s mission is relatively unique because it must maintain constant readiness, 24 hours a day and 365 days a year, to respond to a continuity of government situation requiring the use of 60% of its fleet within 15 minutes.[26] After all, nuclear ICBMs wait for no one. So one would assume that this battalion would be outfitted with only the latest, most reliable equipment, flown by the most experienced and best trained pilots that the US Army can offer. And if that is indeed your assumption, then newsflash: you’re wrong.

The 12th Aviation Battalion operates a mixed fleet consisting of both updated UH-60M Blackhawks (known as “Mikes”) and older UH-60Ls (known as “Limas”). The UH-60M, which began production in 2006, has a modern cockpit with large, detailed, easy-to-read displays and a full suite of automation including an autopilot capable of holding speed, heading, and altitude[3–6:51:00] — sort of the bare minimum you would expect from a helicopter produced in the 2000s. It’s far from revolutionary, unsurprisingly for an upgrade to a platform developed in 1974, but it is, at the very least, adequate. The UH-60L, though, is another story. The Lima, which entered production in 1989, still contains the original model’s intimidating bank of 1970s-style green-and-black analog steam gauges and almost no automation at all — not even an autopilot.[26] Maintaining altitude, speed, and heading in the Lima requires a deft touch and constant attention to the helicopter’s complex manual trim system.[1:13]

Every member of the 12th Aviation Battalion interviewed by the NTSB said they would prefer to standardize to a UH-60M-only fleet and put the Limas out to pasture.[3–6:54:50] This conviction was fueled not only by the Mike’s superior equipment, but also by the fact that the training pipeline for Army Blackhawk pilots had already transitioned to a Mike-only fleet, which meant that new pilots who joined the 12th Aviation Battalion did not normally have any Lima experience and had to be retrained to fly the older version.[26] Needless to say, even though no UH-60 is especially hard to fly by helicopter standards, learning to fly the Mike model with its big fancy displays and its coupled autopilot, only to be assigned to a Lima with its little glowing green steam gauges and fully manual flight controls, presented significant difficulties for pilots.[1:13] A former instructor for the 12th Aviation Battalion’s B company told The Air Current that he had to treat pilots trained on the Mike model but assigned to the Lima as though they were “brand-new” to the Blackhawk.[26]

The reasons why the 12th Aviation Battalion still flew UH-60Ls didn’t come up in my research and is beyond the scope of this article, but my personal impression is that it reflects a broader decay in America’s ability to produce advanced modern military equipment in the quantities required to permit sunsetting of decades-old models. The youngest UH-60L in existence at the time of the accident was 18 years old and the oldest was 36. Most Limas had not yet reached the end of their useful lifespan, but I can think of no good reason why a battalion whose mission was to be ready at a moment’s notice to fly high-ranking officials through some of the most complex airspace in the world should have been assigned anything but the latest model. And that’s not just me being righteously indignant, because the 12th Aviation Battalion’s aging fleet was indeed causing serious operational problems. In fact, battalion leaders had twice asked to transition to a Mike-only fleet, and both times their requests were denied.[36]

Because the battalion needed to have 60% of its fleet on standby at all times, less than 40% of the time was available for maintenance, and as the helicopters aged, they required more and more of it. By the time of the accident, the demands imposed by the mission and the maintenance requirements were making it increasingly difficult to find time for pilot training, which was leading to a slow collapse in pilot skill levels at the battalion.[3–6:53:50] The Army imposed a minimum of 96 helicopter flight hours per year for line pilots, and 60 hours per year — less than a typical commercial pilot flies in a month — for pilots in non-line roles, such as administration or maintenance. But even this paltry value was becoming tricky to achieve, as Army personnel testified at the NTSB hearings that they had to push to get everyone the minimum hours.[3–6:45:00] And while this problem was especially severe at the 12th Aviation Battalion, it’s not unique to it, as the total flight experience of pilots across the entirety of Army Aviation fell by an average of 300 hours between 2013 and 2023.[1:182] That might not sound like a lot to those of us who are used to commercial flying, where pilots can rack up more than 20,000 hours over the course of a career, but in the Army, it’s huge — take, for instance, the three pilots on board the helicopter involved in the accident, none of whom had more than 1,200 total flying hours. At those levels, a 300-hour decrease in average flying hours correlates to a decline in experience of at least 25% for a typical Army aviator. This is backed up by annual flight hour data for the aircraft themselves, which shows that between 2011 and 2025, the average hours flown per year for all Army aircraft fell by more than a third.[36]

At the same time, more and more newly minted pilots straight out of training were assigned to the 12th Aviation Battalion. Coming to Washington with little more than 150 flight hours and no Lima experience, these recruits were unsuited for a special mission battalion and placed a significant burden on the unit’s training apparatus. The 12th Aviation Battalion was not the only Army unit where this was occurring,[26] and it appears to have been due in part to an intentional culling of aviation specialists in the early 2010s that led to a loss of senior personnel. Many seasoned aviators were also lured away by higher paying civilian jobs.[36]

As the problem worsened, in the early 2020s the battalion’s commander twice requested that her unit stop being assigned brand new pilots, but the practice continued anyway. By 2025 approximately 10% of new pilots assigned to the battalion were still new graduates straight out of flight school.[36]

These low-time pilots found themselves part of an organization that had, by civilian standards, only a rudimentary safety culture. Unlike the DCA tower with its history of suppressing safety concerns and retaliating against employees, no current or former 12th Aviation Battalion personnel expressed any apprehension about reporting safety issues.[1:288] However, the battalion lacked most of the quality assurance tools that one would expect to find at a civilian airline. For example, the unit did not have the capability to download and monitor flight data to identify safety trends; the Department of Defense required Army Aviation to have such a program, but the requirement was unfunded, and the Office of the Secretary of Defense had denied the Army’s request for resources to help implement it. As a result the requirement remained unfulfilled at the time of the accident.[1:170]

The battalion did not have a robust safety reporting system in place. The Army’s Combat Readiness Center operated a reporting system called ASMIS (“Army Safety Management Information System”) where personnel could submit mishap or near miss reports, but it was not aviation specific and covered all forms of safety hazards, both on and off duty.[1:171] Besides, no pilots at the 12th Aviation Battalion reported ever having used it.[1:177] The battalion also had a non-anonymous Occupational Hazard Reporting (OHR) system, but there was no central repository for OHR reports, and like ASMIS, personnel reported that it was almost never utilized.[1:175–177] In fact, an Army Blackhawk pilot told me that at “literally every Army Aviation unit” that he was aware of, “no one had ever used ASMIS. It only ever got stuff logged when we had a major inspection coming up, then we would make stuff up to log.”

Whereas a typical airline employs several people whose full-time job is to manage flight safety, the entire Army Aviation Brigade (TAAB), with five battalions under its command, had only one full-time safety manager, and aviation was only one of 14 safety areas for which he was responsible.[1:172, 287] The 12th Aviation Battalion itself had no full-time aviation safety management personnel at all. The safety manager for the battalion was also a pilot and his purview was not aviation-exclusive; he reported spending only about 25% of his time on aviation, with the rest devoted to general occupational safety. The part-time safety officer for B Company similarly stated that only 20% of his work hours were spent on aviation safety, and that he had only ever filed one safety report — a bird strike — during his 18 months with the company. None of the safety officers had ever received any safety reports related to midair collision risk near DCA.[1:173]

A 2023 report by the Government Accountability Office (GAO) concerning National Guard units with a similar part-time safety officer role found that those officers were unable to address their flight safety responsibilities effectively while simultaneously working as pilots. The NTSB concluded that the same was likely occurring within The Army Aviation Brigade.[1:287]

The collective result of these shortcomings was that safety hazards affecting the 12th Aviation Battalion were not being identified, reported, catalogued, or analyzed in a way that would have enabled the unit to proactively address operational risks. I would venture to say that these things might have felt superfluous in an environment where soldiers were handed old, defective aircraft; very little training time; few safety resources; and an intense, high-stakes mission, with the expectation that, like the DCA tower, they would “just make it work.” Everyone at the battalion knew that the lack of training time and the serious maintenance issues were putting everyone at risk, but this probably wasn’t perceived as something that could be addressed by filing safety hazard reports. Because the most significant long-term issues remained outside the unit’s control, the unit never developed a safety reporting culture,[1:288] even though reporting potential hazards still would have had value.

Now, having established this, I want to discuss some of those hazards — and the unit’s shocking ability to overlook risks that seemed obvious to everyone else.

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Aircraft from the 12th Aviation Battalion regularly flew down helicopter Routes 1 and 4 for both VIP transport missions and training, and in fact they were the primary users of those routes. As I discussed in Chapter 3, while the route altitudes were not themselves regulatory, they became mandatory when a controller issued a clearance to fly a particular route as depicted on the VFR helicopter route chart. And that brings me to the question of how the battalion adhered to those clearances, which would turn out to be a significant safety issue.

Chief Warrant Officer 5 David Van Vechten, a former standardization (instructor) pilot for TAAB, testified at the NTSB hearing that in manual flight, federal standards expected that a pilot should, at bare minimum, be able to maintain an assigned altitude within a margin of ±100 feet.[3­ — 3:14:30] This is quite a normal margin at higher altitudes where assigned flight levels come in thousand-foot increments, but becomes abstract to the point of meaninglessness on VFR helicopter routes where the route ceilings are specified in increments of 100. If Route 1 between the Key Bridge and the Memorial Bridge has a maximum altitude of 300 feet, and between the Memorial Bridge and the South Capitol Street Bridge it falls to 200, surely it is not intended that a helicopter transiting the latter segment could fly at 300 feet. At the same time, the SOP at the 12th Aviation Battalion was to fly no lower than 100 feet below the maximum altitude specified on a helicopter route chart,[1:51] which meant that in practice pilots needed to maintain altitude within ±50 feet, not 100, to avoid busting one limit or the other. Van Vechten then clarified that remaining consistently above the maximum would be a problem, but that bobbing occasionally above or below the target altitude was normal,[3–3:14:30] and that the expected human altitude maintenance precision was presumably taken into account when designing the airspace. We now know this assumption to be false, as the clearance between Route 4 and the runway 33 approach path was only 75 feet.

Not everyone agreed with this assessment either. Rick Dressler, a pilot for a DC area medevac operator, interjected to point out that for his company, the route altitudes were a hard maximum and he expected pilots to fly in such a manner that the ceiling was never exceeded.[3–3:15:00]

At the same time, the NTSB discovered that multiple helicopters from the 12th Aviation Battalion suffered from a consistent anomaly that caused their barometric altimeters to read lower than the aircraft’s actual altitude. This is significant because while the barometric altimeters are not normally used for low level VFR flight in a helicopter, it was standard procedure at the 12th Aviation Battalion to reference them in order to avoid exceeding the route ceilings.[1:52]

For my non-aviation readers, it’s important to note that virtually all aircraft are equipped with two different types of altimeters — a barometric altimeter and a radio altimeter. A radio altimeter measures the height above the terrain directly beneath the airplane by bouncing radio waves off the ground. A barometric altimeter measures the aircraft’s altitude above sea level by measuring the static air pressure and applying a local pressure correction provided by air traffic control. Radio altimeters are very precise but can fluctuate wildly if the terrain beneath the aircraft is not perfectly smooth. At the same time, barometric altimeters are less precise but are much more consistent, and because all aircraft in a given area should be using the same pressure correction value, the barometric altitude can function as a common baseline between them. That’s why all altitudes depicted on charts or assigned by ATC are always barometric altitudes unless otherwise specified. Therefore, in order to adhere to the route ceilings shown on the VFR helicopter route chart, pilots were required to reference their barometric altimeters, even though this would not normally be done during low-level VFR flight.

Barometric altimeters are subject to several sources of error. One type is instrument error, caused by the tolerances of the physical instruments, which on selected UH-60Ls from the 12th Aviation Battalion was found to be between 20 and 45 feet.[1:121]

On helicopters, error can also be introduced by the rotor downwash skewing the ambient pressure readings. The ambient pressure is measured using a set of static ports, which on the UH-60 Blackhawk are located on the outboard cabin roof behind the cockpit eyebrow windows.[1:22] Sikorsky stated that on the UH-60, rotor downwash results in a local pressure increase in this area that causes the altimeter to read about 80 feet too low while the helicopter is in a hover, decreasing to zero error as forward speed increases toward 120 knots, after which the altimeter will begin to read too high.[1:120] This is an inherent drawback of the basic layout of any helicopter, although a smaller error could be achieved if the Blackhawk had been designed today thanks to computational flow analysis, which was not available to the Sikorsky engineers who decided where to put the static ports when the UH-60 was designed in the early 1970s.[3–1:04:00]

The error values I just provided were for a basic, unmodified UH-60 platform, but that wasn’t the configuration used by the 12th Aviation Battalion. Their UH-60Ls were equipped with external stores support systems, or ESSS, consisting of a pair of external fuel tanks mounted to wing-like support structures affixed to the sides of the cabin.[1:18–19] Sikorsky was aware that the ESSS produced unintended aerodynamic side effects on the local pressure over the static ports, causing the barometric altimeters to under-read by an additional 40 to 50 feet.[3–1:31:00] This error was not mentioned in the UH-60 flight manual used by the Army; Sikorsky had recommended that it be included, but the Army decides what goes in the manual, and they chose to exclude it. Army representatives stated that this was likely because the error was only 15 to 20 feet out of spec, and the difference would be unimportant relative to the standard radar separation of 500 feet or more.[3–3:31:00] They could not have anticipated the effect it would have on Route 4 at DCA.

Taken in total, if all of these errors stacked in the same direction, the barometric altimeters on the UH-60Ls used by the 12th Aviation Battalion could under-read altitude by more than 100 feet.[1:242] These errors were not detected during routine maintenance test flights because altimeter error was checked prior to engine start, without the influence of rotor downwash.[1:19] Furthermore, there was no in-flight procedure that called for a cross-check between the radio altimeter and the barometric altimeter that could have revealed a difference between them. As a result, pilots and mechanics alike were unaware that the barometric altitude error could be so large. This has to be added on top of the previously mentioned operating policy that allowed for intermittent exceedances of the helicopter route altitudes.

Now consider those 75 feet of separation between Route 4 and the runway 33 approach path. Remember how I said in Chapter 3 that if a helicopter were to cross paths with an airliner at that location, a collision was all but assured if the helicopter was just a few dozen feet above the maximum altitude? Indeed, it turns out that UH-60 pilots were relying on barometric altimeters that could indicate that they were below the maximum when this was not the case. In fact, data later showed that helicopters transiting Route 4 exceeded the 200-foot ceiling 17% of the time.[1:200] That made systematic altimeter error yet another factor increasing the collision risk at that location. Throw it on the pile!

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Obviously, altimeter error was not taken into account when designing the helicopter routes because, as I said in Chapter 3, they were never intended to provide procedural separation from airliners landing at DCA. However, personnel at the 12th Aviation Battalion appeared to be almost universally unaware of this.

Even though pilots at the battalion were given area familiarization training that included ground instruction, orientation flights, and FAA-mandated DC Special Flight Rules Area awareness training,[1:52] Army personnel interviewed by the NTSB displayed a deep lack of knowledge of civilian aircraft operations in the region. Most 12th Aviation Battalion pilots, including the battalion commander and a B company standardization pilot (the Army equivalent to an instructor), told the NTSB that as far as they knew, the 200-foot ceiling on Route 4 was intended to ensure separation from airliner traffic. The latter said he assumed airliners approaching runway 33 crossed the east bank of the Potomac at a height of “500 to 600 feet,” which was twice the actual value.[1:53] At the same time, former standardization pilot Van Vechten testified at the NTSB hearing that as far as he knew, air traffic control wouldn’t allow them to cross the runway 33 approach path when there was landing traffic,[3–3:28:20] which was untrue. He claimed that he had always been asked to hold at Hains Point or the Wilson Bridge when 33 was in use, but other pilots contradicted this, reporting that they used visual separation from runway 33 traffic anywhere from 75% to 100% of the time.[26] However, most pilots agreed that encountering any traffic at all on runway 33 was pretty rare. For instance, one standardization pilot said he had flown Route 4 over 200 times and had encountered traffic landing on runway 33 on “less than 10” of those trips,[1:53] which seems to comport with the statistic that about 5% of landings occur on that runway.

The incorrect and even dangerous beliefs about DCA operations didn’t end there. For instance, when asked what the runway 33 approach pattern was, Van Vechten said he assumed it was a straight-in approach like runway 1 or runway 19, even though it was actually a circling approach that branched off runway 1.[3–4:50:10] So if he was told to maintain visual separation from an airplane approaching 33, would he know where to look? Seemingly not!

The idea that helicopter pilots who regularly fly through DCA airspace might not know where the approach corridors were was unfathomable to many. “Any time that you are operating in the vicinity of an airport, you study the airport chart,” a former Marine Corps helicopter instructor told the New York Times. “You know what the approaches are there. You know what the active runways are there.”[36] The approach corridors aren’t labeled on the VFR helicopter route chart, but approach charts for DCA are easily available with a simple Google search and could have been used to educate Army pilots about the likely locations of civilian airliners. Despite this, the NTSB found that commercial air traffic patterns were not included in the 12th Aviation Battalion’s airspace familiarization training.[3–4:50:10]

To make matters even worse, Van Vechten (or rather an unnamed standardization pilot who appears to be Van Vechten, based on his statements at the hearing) said that while it was easy, even at night, to see a chain of arrivals lined up for runway 1 from all the way back at the start of Route 1 near Cabin John, maintaining visual contact with airplanes approaching runway 33 was much harder, especially with night vision goggles (more on that in Chapter 7). He also admitted to requesting visual separation from aircraft he had not yet spotted, and while he appeared to be referring only to arrivals on runway 1/19, not 33, he added that if he, an experienced instructor, had done this, then other pilots certainly were doing it too.[1:72] And were those pilots aware of where runway 33 traffic would be coming from? Was it possible that they were asking for visual separation from that traffic without actually seeing it, under the assumption that the route ceiling provided an inherent margin of safety that did not actually exist? In fact, the NTSB report says that some 12th Aviation Battalion pilots occasionally flew directly underneath arriving or departing airplanes while under visual separation, but the report did not specify which runway those airplanes were using.[1:52] Pilots at PSA Airlines also reported seeing helicopters “operating below their aircraft” at DCA, but without sufficient precision to say where this took place.[1:158]

The civilian medevac pilot Rick Dressler, himself a former US Army aviator, explained at the NTSB hearing that many military pilots consider some of their aircraft (such as the UH-60L) to be insufficiently equipped for flight through complex Class B airspace, especially when the pilots are used to operating in very different airspaces, like military training grounds. He added that US Army pilots don’t spend long enough in the DC area to develop adequate familiarity with the airspace, including but not limited to its actual layout, the reasons why it’s constructed the way it is, and who has priority within it. Frequent rotation of personnel prevented the accumulation of institutional experience.[3–5:41:20]

Dressler elaborated on the issue of priority by explaining that there is an understood hierarchy of helicopter missions in which law enforcement gives way to emergency medevac; VIP transport and Coast Guard air response give way to both law enforcement and medevac; and everyone else gives way to all four of those missions. That “everyone else” includes the 12th aviation battalion, except when the unit is carrying actual VIPs. But in his view, military pilots did not seem to universally understand this hierarchy, citing examples such as military flights flying through active police circuits without warning or landing at hospital helipads without making any radio calls, including a 2024 incident where an Air Force helicopter landed at a hospital without coordination and blocked a medevac flight carrying a critically ill patient.[3–5:41:20] The situation had become so tense in recent years that in 2021 Aaron Smith, the chief pilot of the Prince Georges County Police, filed a complaint with the Department of Defense.[26]

Because civilian and law enforcement pilots experienced frequent near misses with military helicopters that didn’t seem to be playing by the rules, Smith also helped organize a biannual DC helicopter operators’ fly-in event, inviting all local operators including various military branches. The purpose was to help share institutional knowledge across all operators, improve understanding of each operator’s mission, and make sure everyone was on the same page with regard to airspace use.[26] Participation by the military was initially robust, but it quickly tapered off following a change in command at the 12th Aviation Battalion.[4–8:20:15] Once again, personnel turnover had stunted the battalion’s ability to gain a deeper understanding of the airspace in which they were expected to operate.

Instead, the battalion’s lack of appreciation of the risks it was creating for other airspace users only persisted. After the accident, many people asked why the battalion’s training flights used Route 4 at all, when all of the mission sites could be accessed via other routes; and in fact, it’s not even the shortest way from any of the mission sites back to Fort Belvoir. Why not use Route 3, or even Route 5 and the Pentagon Transition? NTSB Board Member Michael Graham asked this question at the public hearing, and Van Vechten answered that the Army perceived it as the safer route because it was “parallel with 96% of the traffic.” The runway 33 intersection was an afterthought, if it was considered at all. And as for Route 3, which kept well clear of the airport, the main reason for avoiding this route seemed to be to placate “some particular persistent noise complainers.” In fact, Van Vechten told the NTSB straight up, “It’s preferred to take the river southbound for noise abatement purposes.”[3–5:38:25] Aircraft noise is a genuinely huge problem in Washington, D.C. that has real adverse effects on the population living there, but in this case I have to believe the calculation erred the wrong way.

Similarly, it has been asked why the training flights are not held in the middle of the night when there’s not as much commercial traffic at DCA. The Army’s answer to that question is that the timing of the training flights is dictated in large part by minimum rest requirements for any crewmembers who may be on duty the following day, which typically prevents scheduling evaluations at 2:00 in the morning.[3–6:21:00] (This of course raises the question of why next-day duties could not be rescheduled to accommodate training requirements, as they are in the civilian world?) Furthermore, the Army expected to encounter commercial air traffic during an actual continuity of government situation, because they would likely receive the notification to evacuate officials before the DCA tower received word to shut down the airport.[3–5:27:00] Therefore, the presence of air traffic would have been considered part of a realistic mission environment. Ensuring this level of realism during training and evaluation flights was a priority for the Army, as evidence by the text of their Aircrew Training Program, which mentioned that evaluations may be “conducted in the ‘most demanding mode’ that most closely replicated the unit mission.”[1:161]

Evidently, the risks to commercial airliners, especially on runway 33, were not adequately considered when developing these route preferences or training goals. But even if they were, it might have made no difference. According to Colonel Andy DeForest of TAAB, the Army’s risk management process for continuity of government missions ranks security risks above safety risks,[3–3:56:00] so there is every indication that when presented with an option that increases the unit’s readiness to perform its mission but simultaneously increases the safety risk to the public, the brigade’s leaders would choose it. I get that the stakes of their mission are theoretically very high, but where does respect for that mission cross the line into arrogance? Is it before or after the point where civilian lives start to be needlessly lost?

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The 12th Aviation Battalion’s inexperienced pilots, lack of airspace knowledge, inaccurate altimeters, and relative disinterest in commercial aircraft operations further heightened the risk of a collision at the intersection of Route 4 and runway 33, but this risk was also further increased by a lack of effective collision alerting systems aboard the unit’s helicopters.

As I mentioned in Chapter 4, the battalion’s UH-60L helicopters were not equipped with TCAS and therefore could not receive resolution advisories. Six of the unit’s eight UH-60Ms did have TCAS, but according to Van Vechten, the system was not described in the operator’s manual, pilots were not trained on its use, and as far as he knew it was never turned on.[5–1:07:15] It turns out that 12th Aviation Battalion helicopters frequently triggered TCAS resolution advisories aboard airliners approaching DCA, but because their helicopters didn’t have TCAS, the battalion normally never found out about their involvement in these incidents unless air traffic control immediately informed them. No mechanism existed to identify a non-TCAS-equipped aircraft involved in a resolution advisory and inform them in a timely manner, which prevented the battalion from learning any lessons from the events.[1:277–278]

All of the battalion’s helicopters were capable of broadcasting ADS-B Out, which would allow them to appear on the traffic displays of aircraft equipped with ADS-B In. However, as I said in Chapter 4, the Department of Defense had wide authority to permit flights through Class B airspace with the system turned off during “sensitive or classified missions,” because anyone with an ADS-B receiver could track the aircraft’s location. The DoD considered training flights “sensitive” because they normally flew between the actual locations where VIPs would be taken during a continuity of government situation.[1:39] As a result, less than 20% of the battalion’s operations met the criteria for turning ADS-B on.[3–5:51:30] Even then, the NTSB found that several of the battalion’s UH-60Ls, including the accident helicopter, weren’t broadcasting ADS-B Out even when the system was turned on because the transponder units had been improperly configured during installation. The maintenance procedures for post-installation testing of the transponders included steps that would have detected the error, but the procedure evidently had not been followed correctly.[1:245] The lack of ADS-B Out on the accident helicopter had no effect on the accident because PSA flight 5342 didn’t have ADS-B In capability, but it did result in more near misses with other helicopters, whose pilots complained that Army helicopters usually didn’t appear on their ADS-B displays and that the only way to avoid them was by maintaining extreme vigilance.[3–3:28:20]

The UH-60L doesn’t have any native ADS-B In capability, but the unit did supply flight crews with portable ADS-B receivers hooked up to iPad Mini tablets loaded with the ForeFlight app, which is capable of depicting nearby traffic on a moving map display and issuing automated traffic alerts, as described in Chapter 4. Army pilots normally affixed the tablet to their thigh,[1:38] probably to prevent it from falling and interfering with the pedal controls — a scenario that caused a fatal crash of a Boeing CH-47D Chinook helicopter in 2023.[37] The downside of this configuration was that it required the pilot to look down at their lap, away from the windows and the instruments, to read the traffic display. Pilots at the 12th Aviation Battalion told the NTSB that they didn’t look at the iPads during low level flight through Washington, D.C. because the flying and traffic scanning tasks were too demanding.[1:143] Flight crews could still have relied on aural traffic alerts, but the pilots’ headsets on the UH-60L were not capable of receiving audio from the iPads.[1:143] Traffic alerts were still annunciated through the iPad’s internal speakers, but the ambient noise levels inside a helicopter are too high for these alerts to be heard.[1:240]

During the NTSB hearing, Rick Dressler expressed surprise at the Army’s practice of ignoring the ForeFlight display while transiting DC airspace, because in his experience that was precisely when the app was most valuable. With the capability to superimpose traffic, moving map data, helicopter routes, and more, the app greatly enhanced his situational awareness and his ability to precisely follow the helicopter routes. He said he had no problem occasionally glancing down at the display to check the position of nearby traffic even while flying solo under IFR, and he did not understand why Army pilots felt otherwise.[5–3:26:00]

I have to admit my own frustration with the fact that every 12th Aviation Battalion pilot was flying around with a traffic display on their knee that could tell them in an instant where all the nearby traffic was, only to insist upon its non-use while flying through congested airspace in which they were expected to maintain visual separation from traffic. This policy made everyone in that airspace less safe and wasted the benefits of a technology that has saved countless lives.

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What, then, are we to make of this sad portrait? It is widely agreed that there has been a decline in both safety standards and battle effectiveness in the US military over the last 15 years, but every commentator seems to have their own pet diagnosis of the cause. I’m not an expert on military matters, only a close follower of world events, but it’s nevertheless evident that across the US military, decreasing aircraft utilization is leading to less pilot experience and an inability to deploy the latest combat platforms is causing slower adaptation to new technological realities. It all leaves me wondering where the trillion dollars in annual US defense spending is actually going. Is it all disappearing into the hands of contractors who charge the Army $50 for a roll of toilet paper? Does it come back to the ballooning overhead costs, constantly changing design requirements, and costly project cancellations that have recently plagued the development of next-generation military vehicles, ships, and aircraft?

If pilots aren’t flying because the helicopters constantly break down and the higher-ups won’t replace them, that has a corrosive effect on a unit, and morale at the 12th Aviation Battalion was reportedly low.[26] “There was always a lack of gear, there was a lack of training equipment, and commanders always said, ‘Make this happen,’ from the top down,” said the widow of one of the soldiers involved in the accident. “It was a very frustrating [phenomenon] to witness.”[36]

Where have we seen that before? We know what happens when frontline personnel are told to “make it work” or “make it happen” with insufficient support. Often they pull it off, because most people really do want to make the system work, but the hidden cost is paid only later, sometimes in human lives.

Over the decade leading up to the midair collision in Washington, the US Army suffered from an increasing accident rate that was already receiving national attention. The Army conducted a “safety stand-down” in 2023 following a spate of accidents, but the situation didn’t improve; in fact it worsened. In 2024, Army Aviation suffered no less than 17 “class A mishaps,” meaning accidents resulting in fatalities, permanently disabling injuries, or at least $2.5 million in damage — the highest rate since 2007. That year, the Army conducted a “safety stand-up” and provided additional safety training for aviation units,[1:181] but it’s unclear what effect these efforts had, if any. I have seen anecdotal accounts describing the safety stand-down as a “joke.” Regardless of the merits of that description, I fail to see how stopping flights to lecture flight crews on safety would do anything to address the structural issues that seem to be behind the decline in standards.

This seems to reflect something amiss with the mindset of US military leaders. The former army aviator turned medevac pilot, Rick Dressler, described what he saw as “attitude” problems with military aviators.[3–3:28:20]

Tim Lilley, a former US Army Blackhawk pilot who also happens to be the father of PSA flight 5342 First Officer Sam Lilley, felt that a “leadership failure” was the root cause of Army Aviation’s operational and safety problems.[36]

Lilley’s perspective is valuable for our understanding of how leadership allowed safety standards to decay over time. He flew many of the same helicopter routes day in and day out for years, but during a different time period and under different leadership. Back when he flew Blackhawks in Washington, he said, no pilot ever requested visual separation; if there was traffic on runway 33, they held at Hains Point, but sometime in the years since he left, requesting visual separation had become the standard. Lilley called this a “crazy idea,” because from Route 1, with the inbound traffic over six miles away, there was no way to tell at night which traffic one was supposed to separate from.[38] He said that he didn’t know how this tactic had become standard, but if you’ve read this article up to this point, you can probably guess. Since Lilley left the Army in 2006, the amount of airliner traffic at DCA vastly increased, radar separation minima became harder to maintain without ever steeper efficiency compromises, and as efficiency fell, everyone was told to “make it work” or “make it happen” — so they did.

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In a city where the airspace structure itself created collision risks, where the air traffic control tower was experiencing normalization of deviance, where tactics to keep traffic moving efficiently incentivized unsafe behavior, the 12th Aviation Battalion was incapable of managing those risks. Their pilots became more inexperienced with each passing year; their helicopters were old, hard to fly, and broke down constantly; their training failed to provide adequate airspace awareness; they failed to fully utilize the safety technologies that were available; their safety management system was not capable of proactively detecting safety hazards; and their leadership showed a disregard for the safety of other airspace users. Truly, the 12th Aviation Battalion and Washington National Airport were a match made in hell.

Or, if we want to put it another way, consider the NTSB’s findings. “The Army’s ability to maintain an informed understanding of operational risk was constrained by organizational structure and priorities,” they wrote. “These constraints limited the organization’s capacity to synthesize available information and maintain awareness of hazards. … The Army’s safety system lacked the structural flexibility and analytical capability necessary to adapt its safety focus in response to changes in the operational environment. … Organizational learning within the Army was primarily reactive, occurring in response to mishaps rather than through anticipatory identification of weak signals and emerging trends.”[1:288]

Some of us are professionally obligated to be nicer than others.

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Chapter 6: Damned Lies and Statistics

One of the more frustrating aspects of the disaster at National Airport is the sheer number of data sources that pointed to the existence of a problem, and the surprising failure of virtually every official to see the risk written into that data until after the accident. It may or may not have been Mark Twain who said that there are three kinds of falsehoods, “lies, damned lies, and statistics,” but the point is that statistics are only a tool, and almost anything can be read into them depending on how they’re presented. This Chapter tells the story of how those statistics appeared to lie to those whose job was to interpret them.

Modern aviation safety relies to a large degree on what some in Silicon Valley used to call “Big Data,” before they moved on to the next “big” thing. Collecting vast quantities of information about the aviation system and processing it to flag recurring signals of risk is the best and probably only way to predict most accidents before they happen. No human being can look at a complex system and predict with any degree of accuracy how exactly it will fail. But with sufficient data, prediction becomes possible because of something known in the occupational safety field as Heinrich’s Law, which states that there are approximately 300 “near misses” for every serious accident; or as the latest version of the law puts it, each fatal accident is accompanied by about 3,000 near misses and about 30,000 “at-risk behaviors.”[39] Statistically, hundreds or thousands of at-risk behaviors and near misses are likely to occur prior to the first fatal accident, providing an opportunity to identify the risk before lives are lost. In the digital age, this type of adverse trend identification has become easier than ever before, but it is still far from foolproof.

Part of the problem is the sheer variety of independent data collection vectors and the lack of communication between them. In their final report, the NTSB identified at least ten data aggregation and/or analysis systems that collected information capable of being used to identify the midair collision risk that led to the accident. These are listed below.

· The Flight Operations Quality Assurance (FOQA) programs of individual airlines, which collect flight recorder data and feed it to a safety management system (SMS) that analyzes trends internally to the company.

· The FAA’s Air Traffic Safety Action Program (ATSAP) and the Aviation Safety Action Program (ASAP), which collect voluntary safety reports from air traffic controllers and all other aviation personnel, respectively, for review by a committee and inclusion in a proprietary database.[1:190–191]

· NASA’s Aviation Safety Reporting System (ASRS), a voluntary safety reporting system for all aviation personnel that is curated, anonymized, and publicly searchable.[1:192]

· Mandatory Occurrence Reports (MORs), which controllers are required to file when certain criteria are met, collected in a database maintained internally by the FAA ATO.[1:191]

· The FAA’s Near Midair Collision (NMAC) system, a voluntary reporting system where pilots or controllers can submit reports of near midair collisions to a publicly searchable FAA database.[1:191–192]

· The Army Safety Management Information System (ASMIS), the US Army’s non-aviation-specific mishap reporting system, described in Chapter 5.[1:193]

· The FAA’s Aviation Risk Identification and Assessment (ARIA) system, which scans air traffic control radar data to automatically assign a risk value to individual aircraft encounters and flags certain encounters for manual review.[1:193–194]

· The FAA’s Performance Data Analysis and Reporting System (PDARS), which collects ATC radar data for the purposes of analyzing operational efficiency in the National Airspace System, including safety events like go-arounds and losses of separation.[1:194]

· The FAA’s Aviation Safety Information Analysis and Sharing (ASIAS) program, which combines data from ASAP and ATSAP reports, MORs, FOQA data from participating airlines, ARIA, and numerous other sources to identify safety issues and share aggregated safety data with industry stakeholders.[1:184]

After the accident, the NTSB requested data from as many of these sources as they were allowed to access, and came up with some fairly astonishing statistics.

For example, according to ASIAS, at DCA between October 2021 and December 2024 there were 15,214 events in which a helicopter came within 1 nautical mile laterally and 400 feet vertically of a commercial airplane (versus radar separation minima of 1.5 NM and 500 ft); of these, 85 events involved a lateral separation of less than 1,500 feet and vertical separation less than 200 feet.[1:189] If it’s not already clear, that is by most definitions a “close call.”

Other data sources recorded different figures. Between 2011 and 2023, DCA controllers submitted 520 ATSAP reports, including 26 related to close calls between airplanes and helicopters.[1:195] Between 2013 and 2024, DCA tower filed 172,000 MORs, including 90 about close calls between aircraft and helicopters[1:195] (although it must be remembered that DCA management discouraged filing mandatory reports on loss of separation events). Between 1987 and 2021, the NMAC system recorded approximately one near mid-air collision annually at DCA, including three rated as “critical.”[1:196] Between 2022 and 2025, ARIA generated about 24 reportable loss of separation events at DCA per month.[1:199] Between 2018 and 2025, PDARS data showed 4,067 encounters between airplanes and helicopters at DCA in which separation was less than 1,000 feet and 358 where separation was less than 500 feet, or about 5.6 per month.[1:199] And between 1988 and 2024, approximately one NASA ASRS report describing a “close call” between an airplane and a helicopter at DCA was filed each year, many of which described risk factors I’ve already mentioned, such as incomplete or nonexistent traffic alerts, local and helicopter control positions being combined, helicopters not looking in the right place for airplanes approaching runway 33, close calls not alerted by TCAS, and helicopters above the maximum route altitudes.[1:196–197]

The Army reporting system, ASMIS, for its part, did not contain a single report of a near miss at DCA.[1:197]

One of the most important indicators actually used by the FAA was the rate of TCAS resolution advisories (RAs) and traffic alerts (TAs), derived from airlines’ FOQA systems and collected by ASIAS. These data showed that at DCA between 2021 and 2024, a helicopter triggered a TCAS resolution advisory approximately 1.6 times per month, with two thirds of the events occurring at night. In the majority of cases the helicopter may have been above the route ceiling.[1:198]

So, you might be thinking that all of this sounds pretty scary. But was it? Well, that’s a complicated question. One problem is that most of these systems didn’t use the same criteria for defining a noteworthy event, which is because the FAA lacked a standardized way of assigning a midair collision risk value to an encounter;[1:189] in fact out of all these systems, only ARIA assigned a risk value at all. So how close do two aircraft have to come to constitute a near miss? Is there a difference between a near miss, a close call, and a loss of separation? What about operational context — for example, how do you account for the type of separation being applied? At the time of the accident, these questions didn’t really have reliable answers. As far as I can tell, every collection method either imposed its own unique standard or had no standard at all.

One major problem identified by the NTSB was an overreliance by the FAA on TCAS data specifically when defining areas of elevated collision risk. For instance, ASIAS had identified some elevated collision risk near the Memorial Bridge and the Wilson Bridge, but nothing at the intersection of Route 4 and runway 33, even though controllers at DCA knew this was a serious risk area. It turns out that this is because ASIAS was relying on resolution advisory data, which didn’t capture any near misses below the RA inhibit altitude of 900 feet. Traffic alert data was captured closer to the airport, but only half of the airlines whose FOQA data was used by ASIAS retained any data on TCAS TAs.[1:205] PSA Airlines’ own FOQA system also failed to detect any midair collision risk at DCA for the same reasons.[1:203–204] In fact, the rate of TCAS RAs at DCA was utterly unremarkable, ranking 114th out of 257 airports surveyed.[1:198]

Another problem was that some data sources capable of detecting midair collision risks weren’t being used for that purpose at all. For example, when ARIA flagged an event, the FAA ATO checked it for regulatory compliance, but the data was not used in aggregate to find locations with a high collision risk.[1:175] Similarly, PDARS proximity data wasn’t provided to ASIAS and wasn’t used in aggregate to identify risk areas.[1:194, 198] PSA Airlines’ own safety management system had access to ASIAS information, but because ASIAS was evaluating collision risk based on TCAS data and not objective proximity data derived from radar readouts like ARIA and PDARS, PSA had no more ability to detect the risk area than the FAA did.[1:275]

The NTSB also identified what it viewed as a tendency to analyze loss of separation events on a case-by-case basis, with separate, internal analyses carried out by each stakeholder — such as the airline or the tower — without examining the larger picture. When ARIA flagged an event, the operators involved were not informed, and airlines who experienced TCAS RAs had no way to notify the operator of the second aircraft.[1:277] The only stakeholder that ever identified collision hotspots at DCA was the tower itself, but as I discussed in Chapters 3 and 4, their attempts to resolve the issue were shut down by the ATO and the charting office without corrective action.

The tower’s ability to address this known issue was also hampered by shortcomings in the ATO’s safety management system, as well as its isolation from other stakeholders. Despite a 2021 report by the Government Accountability Office recommending that the FAA create a mechanism for safety information exchange between the FAA and DC-area operators, at the time of the accident there was still no formal venue for coordination between these parties, which helps explain why helicopter operators who appeared to be well aware of the risks were never able to escalate their warnings. Their only option was to share their safety concerns with the informal Helicopter Working Group, whose recommendations — several of which may have prevented the accident — were strangled in the crib without so much as a paper trail. In their final report, the NTSB strongly criticized the ATO’s complete dismissal of its own frontline employees who knew the most about the traffic situation at DCA.[1:278–279] It has to be emphasized that no matter how much data the FAA collects and how much money it spends to analyze it all, one of the cheapest and most effective ways to identify safety hazards will always be to listen to frontline personnel and take their concerns seriously. If the FAA isn’t going to do that, then the value of collecting all this data diminishes significantly.

The ATO nominally possessed a safety management system just like an airline, which was intended to capture safety reports and data and identify unsafe trends. But at DCA, the system only existed on paper: the former quality control specialist, who I quoted extensively in Chapter 4, told the NTSB that she could not recall anyone receiving any training on safety risk management or the SMS, and added that she “did not believe that the facility even knew what [an] SMS was.”[1:188]

The NTSB also called out the failure of The Army Aviation Brigade to implement, or the Department of Defense to facilitate, the flight data monitoring program that they were theoretically required to have. In their final report, they wrote that if TAAB had a FOQA system, they might have noticed that helicopters were routinely exceeding the helicopter route altitudes, and might have concluded that with a route ceiling of 200 feet and a battalion minimum of 100 feet, the acceptable altitude range on Route 4 was less than the normal barometric altimeter error range, necessitating operational adjustments.[1:285] The NTSB also faulted the Army’s lack of a reporting culture, which as I said in Chapter 5 could have been rooted in a lack of confidence that reporting a safety issue would result in the issue being addressed, as well as concern over the consequences of filing a report, and/or the effort to file a safety report being too high.[1:286]

Overall, the NTSB wrote that the Army was still in the early stages of implementing safety management best practices that had existed in commercial airlines for years or even decades, with barriers to the process including the safety management system’s widely distributed responsibility, wide scope, and lack of funding.[1:286–287] The Army also had no access to ASIAS or any other FAA data collection and sharing tools.[26]

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With the benefit of hindsight, it’s clear that the FAA had all the data it needed to identify a serious collision risk between helicopters and airplanes at DCA. However, the agency’s process of aggregating and analyzing that data had not caught up with its own ability to collect it. Data collection vectors had proliferated in recent years, and systems even existed to analyze objective proximity data and use it to calculate collision risk areas, but these systems were not integrated effectively. The FAA had attempted a form of integration through ASIAS, but that system, created in 2007, did not effectively utilize more recent radar data analysis tools like ARIA and PDARS, which were capable of identifying collision hotspots in a semi-automated manner. Instead, the FAA continued to rely on outdated metrics like TCAS resolution advisory rates, which contained large and ultimately fatal blind spots. And the most valuable data source of all — the FAA’s own personnel — was routinely ignored.

In an organization as large as the FAA, it’s easy to end up with a half a dozen parallel systems, all oriented toward the same goals, but with little communication between them and little awareness of the other systems’ existence among their respective personnel. Solving this problem is even harder, because let’s say there are 6 different flight data collection and analysis systems that all could be used to monitor collision risks, and a proposal to create a new system integrating all the other systems lands on the Administrator’s desk. The Administrator says “that’s a great idea” and puts their signature on it. Congratulations, now there are 7 systems.

Integrating these systems is also complicated by the fact that each captures data in different formats and applies different, sometimes subjective criteria for estimating the seriousness of an event.

In the end, it was the frontline employees, the air traffic controllers themselves, who saw the problem and tried to fix it, but they were not given the tools to do so. Mid-level managers shut down their efforts because they didn’t want to rock the boat. And so the people who saw the whole picture were denied the power to change it, and those who did have the power to change it refused to see the whole picture, unable to appreciate a problem that was staring them in the face because the statistics they monitored were lying to them. And what a damned lie it was.

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Chapter 7: The Flight of PAT 25

By the 29th of January 2025, all the pieces of the puzzle were already in place, and had been for years.

As political interests forced DCA to accommodate more and more airliners, capacity constraints, too-high arrival rates, miles-in-trail issues, and opportunistic airline schedules increased the workload on air traffic controllers, especially during peak hours in the afternoon and evening. As controllers struggled to handle the waves of excess traffic, they began to engage in widespread shortcutting of standard procedures, apparently with buy-in from managers who knew that following all the rules would reduce efficiency, increase delays, and harm DCA’s performance metrics.

Meanwhile, a helicopter route designed by the Department of Defense to serve its own mission requirements was established almost directly through the approach path to runway 33 without adequate analysis of the resulting collision risks, simply because the routes were never officially intended to provide separation from fixed-wing traffic. Separating airliners from helicopters on Route 4 became the responsibility of the already overworked controllers, who offloaded this task to the helicopter pilots themselves by applying visual separation. Even though the effectiveness of visual separation is severely constrained by the inherent limitations of human perception, it became the primary method of resolving conflicts on the two intersecting routes. Traffic alerts, intended to mitigate these limitations, were applied inconsistently or incompletely, and collision warning systems intended to act as a last line of defense contained both regulatory and design vulnerabilities that significantly limited their usefulness in preventing collisions at the intersection of Route 4 and runway 33.

Many controllers and local pilots understood the risk of a collision at this location and attempted to press for changes to the airspace configuration, only to find that political and military interests stood in the way. Due to outdated metrics and a lack of integration of objective proximity data, safety analysis systems intended to identify hazards were not used in a manner that would have independently revealed the collision risk. As a result, the unsafe condition persisted.

Meanwhile, changes in the nature of the helicopter traffic transiting this route increased the risk even further. The vast majority of the traffic on Route 4 always belonged to the 12th Aviation Battalion of the US Army, but in recent years the battalion’s pilots had become less experienced as aging Army aircraft broke down more often and training hours became harder to acquire. At the same time, experienced personnel left or were purged, and their green replacements were unfamiliar with the unit’s older, more demanding helicopters. As this transition took place, institutional knowledge of the Washington airspace was also lost. Pilots understood that they needed to accept visual separation in order to keep traffic moving efficiently, but they lacked even basic knowledge of the traffic pattern, preventing them from maintaining separation correctly. The battalion’s collective knowledge had so deteriorated that no one recognized the true collision risk anymore, and the unit took actions that routed more helicopters through the risk area even when it was unnecessary to do so.

As a result of all of these factors, a collision became virtually inevitable. It was only a question of who would draw the short straw. What follows is the full story of that unlucky crew and their final, ill-fated flight.

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On the evening of the 29th of January, three 12th Aviation Battalion pilots reported for duty at Davison Army Airfield at Fort Belvoir, Virginia for a scheduled training flight. Undergoing her annual evaluation that night was Captain Rebecca Lobach, a 28-year-old staff officer from Headquarters Company who led that company’s oils and lubricants platoon but remained with B Company’s training program.[1:12]

Lobach had come up through the Reserve Officer Training Corps (ROTC) program, and according to her close friend and roommate, who was also a servicemember, she would have preferred to become an Army doctor, but those roles were hard to get right out of ROTC. Instead, she chose to pursue flying, hoping that she would be assigned to a medevac unit where her passion for medicine would be put to good use, and because she liked to challenge herself and saw aviation as the most stimulating Army career path that was available to her.[40:44–45] Despite struggling with what she believed to be undiagnosed and unmedicated ADHD, which forced her to study harder and more methodically than other students,[40:41–43] she completed her UH-60 Blackhawk training at Fort Rucker, Alabama without major difficulties despite delays caused by the coronavirus pandemic.[40:47] Unfortunately, however, she was not assigned to a medevac unit, but rather to the 12th Aviation Battalion immediately after completing flight school in 2021,[1:12] becoming one of the brand new, inexperienced pilots that the battalion leaders had wanted to stop receiving. And like others in her position, she had been trained to fly the UH-60M, only to be assigned initially to B Company with its fleet of older UH-60Ls, forcing her to learn many flying skills over again from scratch.[1:13][40:49–50] Despite later moving to an administrative role with Headquarters Company, she continued flying B Company’s Limas for training purposes.

According to Lobach’s roommate, flying was never her passion; instead, she wanted to become a psychiatrist, and at the time of the accident, she had already begun applying to medical schools in preparation for what she must have seen as an imminent future outside of aviation.[40:45–46] At the same time, she faced a considerable volume of administrative work due to her staff officer position, which included trying to squeeze in training schedules around the mission and maintenance requirements, a task that was becoming increasingly difficult.[40:48] As the leader of a new oils and lubricants platoon, she was also responsible for updating the Company’s oil and fuel program, which required considerable effort.[40:94] And on top of all that, she also worked as a volunteer social liaison at the White House, where she represented the Army at Medal of Honor ceremonies and other social events.[40:86–87] Despite all of these duties, she was still expected to maintain currency as a pilot, which she found very difficult to do, especially when scheduling any training time for herself inevitably took it away from a frontline officer instead.[40:52] In my opinion this reflects a difference in mentality between the Army and the Air Force, where the latter employs pilots who also happen to be soldiers, while the former employs soldiers who also happen to be pilots. The problems with the latter arrangement are self-evident, as staff officers like Lobach clearly struggled to balance their administrative duties with the need to maintain flying skills for a mission they were not actually on standby for. In fact, Tim Lilley, the former Blackhawk pilot, has argued that taking staff officers off the flight roster entirely would be a better use of resources.[41]

Because of her position and the difficulty of acquiring experience, Captain Lobach only had 454 total flying hours at the time of the accident, of which 326 were on the UH-60. She had flown only 56 hours in the past year,[1:12] below the already inadequate minimum of 60 for non-line pilots, due to a knee injury that kept her off the flight line for three months in 2024.[41] And in the two months before the accident flight, she had only flown for 4.4 hours,[1:12] in part because she forewent flying duties during the month of December in order to support her White House liaison role.[40:52–53] Taken in total, then, it cannot be said that Lobach was an experienced pilot; in fact, quite the opposite was true. With 454 hours, she would be ineligible to apply for a First Officer position at a commercial airline in the United States, and even in countries where airlines can hire First Officers right out of flight school with 250 hours, she would have been considered a rookie. However, it was normal to become a pilot-in-command at her experience level in the Army.

Her lack of regular experience, particularly on the more demanding UH-60Ls, was evident in her training record. An instructor who taught her after her arrival at the battalion said she was eager to learn but struggled with stick-and-rudder flying skills; she eventually achieved the highest readiness level, but just one month later was downgraded again after an instructor graded her skills as “well below average.” By 2024, instructors had largely stopped giving adverse evaluations, reporting that her skills had improved to the “average” to “good” range, and she had developed a reputation as a diligent and professional pilot.[1:13] Nevertheless, her lack of flight time in the year leading up to January 2025 had no doubt caused some decay, which could have allowed earlier difficulties to resurface. A pilot who flew with her on January 27th stated that she seemed rusty.[1:14]

On the night of the 29th, her instructor was 39-year-old Chief Warrant Officer 2 Andrew Eaves, a career officer who began his service with the US Navy in 2007 before switching to the Army in 2017. He completed flight school in 2019 and was assigned to the 12th Aviation Battalion, where he became an instructor in 2023, a job to which he returned in 2024 following a deployment to Honduras.[1:15] According to his wife, he had always wanted to fly and aspired to work in aerial firefighting after retiring from the Army.[40:108] His fellow pilots described him with terms ranging from average to very good, and the B Company safety officer said he flew “by the book.”[1:16] However, despite his years of experience and instructor position, he had 968 total flying hours, including 301 on the UH-60L — a normal amount for an Army instructor of his seniority, but still far short of the normal minimum to become a commercial pilot.[1:15] Although he had flown 269 hours in the last year, considered a very large number in the Army, that’s still only a quarter of what a commercial pilot might expect to earn during the same time period. So, once again, while the Army may insist that these were “experienced pilots,” and they were by Army standards, as a civilian it astounds me that Army standards were so low.

Interviews with his next of kin revealed that Eaves had separated from his wife and was having an affair with a woman in California. She told the NTSB that a few days before the accident, Eaves had expressed concerns about Captain Lobach’s abilities, stating that she was “not where she should be” at that point in her flying career.[40:280] This is rather unsurprising given Lobach’s lack of recent experience, but it’s important to mention it because it ought to have informed Eaves’ mindset during the evaluation flight. Certainly he was aware that he would be evaluating someone who was not currently at peak performance.

The third and final member of the crew was 28-year-old Staff Sergeant Ryan O’Hara, who would occupy the position of Crew Chief. On the Blackhawk, the Crew Chief’s duties include acting as a third pair of eyes to scan for traffic and identify obstacles; he was also responsible for assisting with certain in-flight and pre-flight tasks, acting as a spotter during certain types of complex landings, overseeing any passengers or cargo, and a few other miscellaneous items.[1:2–3]* He was actually the most experienced crewmember, with 1,149 total flying hours over nearly eight years with the 12th Aviation Battalion. His colleagues spoke favorably of his abilities, his personality, and his ability to spot traffic.[1:17]

*Note: The NTSB report lists a large number of additional duties, however after speaking with a US Army Blackhawk pilot, it appears that most of these are things the Crew Chief needs to be able to do, rather than things they actually do on a typical flight.

The instructor, Chief Warrant Officer 2 Eaves, was the pilot in command of the flight. However, it’s worth noting that outside of the cockpit, Captain Lobach outranked him. Although this wouldn’t have been especially uncommon in an evaluation setting, it’s still possible that this fact could have introduced uncertainty into the cockpit command structure.[41]

That night, the plan was to conduct both Lobach’s annual evaluation and her annual Night Vision Goggles (NVG) check, which were normally combined into one exercise in order to save time and to more closely reflect the mission environment.[1:161–162]

NVGs enhance pilots’ vision at night by artificially amplifying light levels. The accident flight crew was provided with helmet-mounted binocular type NVGs that could be rotated down into the pilot’s field of view, or up and away when regular eyesight was needed; the goggles used monochrome displays in either white or green and provided a 40-degree field of view.[1:110–111]

Overall, NVGs are extremely useful for operating in very dark areas, but on a flight through Washington, D.C. they come with a number of disadvantages. Widespread urban lighting reduces their effectiveness because of the high contrast between the lights and shadows, whereas an area that is uniformly in shadow will show up more clearly. Additionally, NVGs significantly degrade a pilot’s depth perception in ways that make traffic scanning more difficult. Illuminated aircraft appear through NVGs only as points of light,[1:110–111] and there is no way to reliably discern relative distance between multiple aircraft because an aircraft that is more brightly lit will appear to be closer, even if this is not the case.[1:238] The monochrome display also prevents pilots from using the red and green navigation lights to discern which direction the traffic is moving,[5–0:30:30] and the 40-degree field of view also interferes with peripheral vision, forcing pilots to move their heads more, or temporarily flip up the NVGs, in order to effectively scan for traffic.

For these reasons, the Coast Guard stated that they preferred not to use NVGs while passing through Washington, D.C., and some Army pilots testified that in their experience they needed to flip the goggles up — called “going unaided” — in order to spot traffic, but the Army had no procedure or policy recommending that they do this.[26] And since this was an NVG evaluation, it was expected that the pilots — especially Captain Lobach — would use the NVGs throughout the flight.

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Back at Davison Army Airfield, the flight crew filed a VFR flight plan that would take them west to a private grass airstrip, called Greenhouse, located in Culpeper, Virginia; then north to a helipad at the underground Olney Support Center in Laytonsville, Maryland; and finally back to Davison Army Airfield.[1:2][41] As this was a VFR flight, the exact route taken between these points was up to the instructor, Chief Warrant Officer 2 Eaves. However, it was expected that he would perform the evaluation flight in a manner resembling the actual mission, which is why those two destinations — both of which were actual mission sites — had been chosen.

With Eaves in the right seat, Lobach in the left seat, and O’Hara seated behind Lobach in an auxiliary seat, the flight departed at 18:45 with Eaves at the controls,[41] operating under the callsign PAT 25. The weather was cool but not cold; the sky was clear but the wind was fierce and turbulent, with gusts as high as 33 knots reported in the Washington area.[1:40] It would have been a tricky night to hand-fly a Lima.

As the crew navigated west toward Culpeper, the published cockpit voice recorder transcript began at time 19:11. Eaves was still the pilot flying, while Lobach monitored the instruments, called out deviations and obstacles, and helped find the landing site. So far everything on the flight deck seemed normal, although the pilots complained that the intense lighting inside the greenhouse at the Culpeper landing strip was blinding them through their NVGs.[42:18–19]

After identifying the field, Eaves handed the controls to Lobach in order to evaluate her landing proficiency. The transcript doesn’t suggest that Lobach had any trouble with the landing, and by 19:22 they were safely on the ground, although both pilots noted that they were slightly behind the mission schedule due to the high winds. Eaves then took back the controls, and Lobach acknowledged.[42:23–24] “Yeah, I’m going to use that strip more. make people fly into that ### greenhouse,” he joked.

“Yeah yeah,” Lobach replied, her sarcasm bleeding through even in textual form.[42:26–27]

After just under seven minutes on the ground performing routine checks, Eaves said “Whenever you’re ready ma’am.”

Lobach announced she was ready, and 19:29 Eaves lifted the helicopter back into the air, climbing away through the clear night sky over Virginia to a new cruising altitude of 2,000 feet. Lobach requested flight following from the Potomac TRACON as they headed northeast toward their next destination, the Olney Support Center in Laytonsville. For now though, they remained outside the more tightly controlled Class B airspace.[42:31–35]

After cruising for some time, at 19:41 Lobach noticed that they had slowed down and descended to 1,600 feet, when they should have been at 2,000. She asked Eaves whether that was intentional, and when she didn’t get a clear response, she decided to assume the role of pilot flying, announcing that she had the controls. The request seemed to catch Eaves by surprise, but after clarifying the matter, he happily handed over control, since Lobach needed to be evaluated in both the monitoring and flying roles regardless. The pilots then clarified that Eaves had misread his altimeter and believed they were at 2,600 feet — an error that highlighted his own inexperience, despite his instructor role.[42:39–41][41]

After getting them back up to 2,000 feet, Lobach almost immediately began to complain of strong headwinds and heavy chop, so at 19:43, less than two minutes after relinquishing the controls, Eaves took them back.[42:41–42] So far, they had been airborne for almost an hour and Lobach had flown the helicopter for only about three and a half minutes.[41]

At 19:46, a master caution alarm sounded, and the crew identified a failure of the stabilator’s automatic mode. According to the Blackhawk pilot I spoke to, this was almost certainly triggered intentionally by Eaves to check Lobach’s competence in responding to emergency procedures and was not a real failure.

Manual control of the stabilator, which controls pitch, remained normal, so the crew confirmed that the aircraft was still stable, then reset the system.[42:45–46] Lobach then pulled out the emergency procedure and read over the items, but concluded that because they hadn’t observed any control anomalies and the system had reset successfully, no further action was needed. However, Eaves pointed out that she had attempted to troubleshoot from memory before pulling out the procedure, which they’re not supposed to do. “The whole point of the F-R-Cs is cause we end up killing ourselves because we do something without confirming and verifying,” he said. “It is a tough mentality to just slow down, ‘I know how to fix this but I’m going to read the book anyways.’ But that’s — you know that’s what they want. That’s what we’re looking for, so.”

“Okay, thank you, yeah,” Lobach acknowledged. “You’re absolutely right. I sometimes forget that.”[42:49–52]

At 19:53, Lobach mentioned that she was feeling “a little dizzy like looking down and around with the winds or whatever it is, but not too bad.” Eaves acknowledged but made no further comment about it.[42:54] It’s not clear whether he was aware that Lobach had previously struggled with vertigo and acrophobia, something she had worked to overcome during training.[40:46] Night vision goggles can make vertigo worse,[4–09:05:20] and especially with so little recent experience, it’s possible that a little bit of that condition was starting to return. In fact, this was but the first of several offhand comments and incidents suggesting that after an uneventful first hour of the flight, Lobach was now beginning to feel unwell.

Continuing north from Virginia into Maryland, the crew’s discussions mostly focused on handling the difficult wind conditions, other than a brief period spent searching for helicopter traffic alerted by the Potomac TRACON. Then, at 20:01, Lobach asked to take the controls again, and Eaves happily handed them over.[42:60] For several minutes she handled the gusty winds with no apparent problems; the instructor, meanwhile, monitored the common terminal frequency for nearby Gaithersburg Airport in order to stay on top of any general aviation traffic in the area.

At 20:14, they approached the Olney Support Center, and Eaves asked what he should look for on the ground to identify their landing site, but Lobach couldn’t remember. “I’d have to look at my notes,” she said. But Eaves soon spotted the helipad anyway and began coaching Lobach toward it.[42:72–74]

The landing seemed to be proceeding normally, as Lobach caught sight of the pad and worked with Eaves to make sure they were clear of any obstacles. But suddenly, at 20:18, Eaves hurriedly said, “Go around, go around, go around,” and Lobach pulled back and increased speed to abort the attempt. He didn’t say why, but Lobach acknowledged the reason just a few seconds later: a deer had seemingly wandered onto the helipad.[42:77–78]

As they pulled away to the right, Eaves urged her to reverse direction and go around to the left so they could face into the wind and keep their speed down. Lobach agreed and turned to the left before initiating a second attempt, but before it got very far she said, “Yeah, I’m not sure, I’m — I’m — ”

“What’s up?” Eaves asked.

“This doesn’t feel right,” Lobach insisted.

Eaves suggested that the feeling might be due to the gusty winds kicking them around and encouraged Lobach to continue, but her confidence was at an all-time low.

“No indicated airspeed even though I’m barely pulling the aft cyclic,” Lobach said.

“Yup, pull in some power,” Eaves suggested.

“Okay, pulling in a little more.”

“Should have the pad in sight.”

“I do, I’m too high again though,” Lobach complained.

“Nope, you’re good, so I’d maybe — a left pedal a little bit to put yourself into that wind.”

“’Kay.”

“Continue. You can start your approach, you’re gonna be a little high.”

“Yeah, I — I’m not comfortable landing there,” Lobach insisted.

Eaves accepted her judgment. “Alright, cool.”

“I’m clearing out. I probably could. It’s handling funny,” Lobach continued.[42:78–82]

Eaves then offered to land the helicopter himself, and Lobach handed the controls over to him. As he maneuvered the helicopter toward the pad, he narrated his every action, using the awkward moment as an instructional opportunity.[42:83] In fact, throughout the transcript, it’s apparent that Eaves was a conscientious and patient instructor who wanted his student to succeed, but by this point he might have been starting to feel that his concerns about Lobach were coming true.

At 20:24, Eaves set the helicopter down on the helipad, and the pilots debriefed the failed approaches. Eaves even offered to let Lobach have another shot at landing, but she politely declined, insisting that she was “good with the demonstration.”[42:87]

It has been argued that Lobach’s failure to complete the landing maneuver ought to have resulted in an unsatisfactory grade and the termination of the evaluation.[41] However, according to the Blackhawk pilot I spoke with, the evaluation would not normally be terminated even if the trainee commits an error that results in an automatic fail.

Furthermore, there are risks associated with automatically failing a student for declining to complete an approach that she did not feel was safe, since it could cause students to start pushing ahead in situations that exceed their skill level, potentially creating an unsafe condition. Eaves would have needed to weigh this fact against the equally real expectation that a pilot for the 12th Aviation Battalion should be able to land a UH-60L at night in gusty wind conditions while using NVGs. Therefore, it’s entirely incorrect to fault Eaves for allowing the evaluation flight to continue.

At 20:28, Eaves lifted the helicopter into the air for the third and final time that night, climbing toward 1,000 feet as he steered them back to the south toward Fort Belvoir. Four minutes later, Lobach contacted DCA tower on the helicopter frequency and requested to fly to Davison Army Airfield via Cabin John, Route 1, and Route 4, straight through the heart of Washington.[42:95]

There did not appear to have been any serious discussion about whether or not to fly home via this route, which would take them right through the busiest airspace in the region during the evening arrival push. While on the ground at 20:25, Eaves had briefly mentioned heading south via Cabin John and the Chain Bridge, which lies along Route 1, couching it with the phrase, “if that’s where you want to go,” but no one ever suggested any alternative.[42:88] The transcript gives me the impression that the pilots saw Routes 1 and 4 as the default way home, to the point that it was not really even a question. That would be consistent with the testimony I described in Chapter 5, in which the battalion considered Routes 1 and 4 to be the best and safest path south, despite overwhelming evidence to the contrary. This lands a second death blow to the argument that the evaluation should have been ended early, because it is not at all clear to me that the route home would have looked any different from that point onward regardless of whether Eaves intended to continue or terminate the evaluation.

In any case, the tower did not immediately approve the routing request because the controller didn’t know who was calling. Instead, Eaves offered to hand the controls back to Lobach, which she accepted.[42:95–96] Most likely this was because she hadn’t flown the full required training time or performed all the required maneuvers yet. However, giving the controls back to the struggling trainee through the trickiest airspace on their entire route would have some unintended consequences.

At 20:33, following up on the earlier transmission, the DCA tower asked PAT 25 to squawk ident, meaning that he wanted the crew to press the “IDENT” button on their transponder panel, which would highlight the helicopter’s location on his radar display. The pilots did so, and the controller spotted them 6 miles north of Bethesda, at which point he asked again for their intentions, and Eaves repeated their request. The controller quickly shot back, “PAT 25, approved.”[1:342–343]

Throughout these transmissions, the helicopter’s cockpit voice recorder captured static, muffled speech, and dropped words, indicating a poor radio connection with the tower. The pilots complained about the intelligibility multiple times and even tried increasing the radio volume, but it was already at the maximum. Lobach asked whether the tower had access to military UHF radio, thinking that it might sound better, but Eaves correctly doubted the tower used UHF, and they stuck with the civilian VHF instead.[1:344–346] In the background, a constant stream of chatter lit up the radio, barely allowing anyone to get a word in edgewise. Little did the crew of PAT 25 know that they were about to fly into a hornet’s nest.

◊◊◊

On duty at the DCA tower at that moment were five controllers, plus a Supervisor, a trainee controller, a trainee Supervisor, and a Traffic Management Coordinator (TMC) on duty. The Clearance Delivery and Flight Data positions were combined, as usual; a second controller was working Ground, and a third was working the combined Helicopter and Local positions. The TMC was temporarily filling the Assistant Local control position, while the Supervisor monitored all four other controllers.[1:61] In the interest of their personal safety, the names of the controllers on duty that night have not been released.

The Local controller was 36 years old and had begun working at DCA in October 2022, before qualifying for the Local and Helicopter positions in May 2024. He had reported for duty feeling well rested and was now several hours into his shift, having already worked stints in the Clearance Delivery/Flight Data and Assistant Local control positions before switching to Local/Helicopter at 19:28.[1:61]

The Assistant Local controller was 41 years old and had been working at DCA for two years; although she was primarily a TMC, she still had to work regular ATC positions from time to time to maintain currency, which is why she was assisting the Local controller that night.

The Supervisor was 36 years old and had worked at DCA for a total of almost 9 years.[1:68] When he arrived on duty, he found that the previous Supervisor had already combined the Local and Helicopter positions, and he had no way of knowing why because the requirement to document that decision had been removed, but by his assessment the traffic situation when he started his shift at 16:30 was not complex enough to warrant de-combining the positions.[1:69] If he wanted to staff the positions separately, he could have done so, because several staff — including two full controllers — were conducting training in another room and could be called back at any time; thus, perceived short staffing played no direct role in the accident.[4–7:43:20]

Around 20:00, the Local controller experienced a large increase in traffic — known as a “push” — after which his workload decreased; however, beginning around the time PAT 25 contacted the tower, the traffic situation again increased in complexity and he started to feel a little overwhelmed. At that time the TRACON wasn’t giving them the requested four miles in trail, and planes were lining up waiting to depart from runway 1 because there wasn’t enough room to sneak them out between the arrivals. In fact, after 20:15 that night, 9 out of 16 arrivals had less than four in trail, including flight 5342, which was too close behind the flight ahead of it.[1:75–76] Unable to meet the four mile spacing request, the TRACON requested at 20:38 that the tower withdraw it, and the Supervisor agreed.[1:76] As a result, the Local controller had to start asking more flights to take runway 33, among them PSA flight 5342 at time 20:43.[1:62]

Despite feeling overwhelmed, the Local controller didn’t ask that the Supervisor split off the Helicopter control position because — as I established in Chapter 4 — he had no guidance against which to judge when it was appropriate to make such a request. And so the situation persisted, even as more airplanes and helicopters continued to pour into DCA airspace.

◊◊◊

On board PAT 25, as they approached Cabin John, the pilots initiated a descent to 1,300 feet, the maximum altitude for Route 1 in that area. But as the Potomac River stretched out before them, Lobach appeared to become disoriented. Instead of turning left to head downriver toward Washington, she turned right and started heading upriver, prompting Eaves to say, “What’s up ma’am, where we going?”

“Down the river, uh Route 1 to 4,” Lobach replied.

Eaves pointed out that they were heading west toward Great Falls, and Lobach quickly turned the helicopter around to put them back on course.

By this point it seems like a number of alarms should have been going off in the instructor’s head. Lobach had complained about dizziness, felt unable to land amid gusty winds, and now turned completely the wrong way, indicating a lack of awareness of her position relative to the Potomac River, the defining geographical feature in the region. Was she experiencing vertigo again? Was she feeling unwell? There’s no way to make an empirical determination, but it is worth noting that at the NTSB hearing, member Inman asked the brigade standardization pilot, David Van Vechten, what these signs of possible vertigo from a fellow pilot would say to him as an instructor, to which he replied that it would “heighten my sense of awareness for sure.”[4–9:13:10] Nevertheless, Lobach remained at the controls. Whether Eaves’ sense of awareness was heightened, no one can know. All I can say is that I sympathize with Lobach, and I’m glad that of all the times I’ve felt the way Lobach may have been feeling, I never had to deal with it while flying an aircraft.* People often feel like crap for reasons that will never show up in a post-mortem examination or a next-of-kin interview, whether it’s because they ate something that isn’t sitting right, or they feel a cold coming on, or they’re worried that they left the stove on, or they’re afraid they might fail an evaluation. Any of these could interfere with their ability to put 100% of their attention into the task of flying, but after the fact, all anyone will see are the resulting mistakes. And there’s no incentive to speak up, because if one does, the answer is usually, “everyone feels like crap sometimes, just deal with it.” But the reality is that these everyday discomforts have probably contributed to more accidents than we will ever know.

*Before anyone starts asking questions, I’m not a pilot and have never flown an aircraft while in any state of health, good or bad.

Over the next several minutes, PAT 25 made its way downriver, descending to 700 feet before passing the Chain Bridge, followed by a descent toward 300 feet, the route ceiling south of the Key Bridge. Moments later, at 20:43, PSA flight 5342 joined the DC tower frequency as it headed north toward runway 1. To the crew of PAT 25, the controller’s reply to “Bluestreak 5342” was nothing more than another snippet of endless background radio chatter.[1:356–361]

The gusty winds were still giving Lobach a hard time. “Getting choppy close to the ground,” she commented. Eaves agreed that as they descended, the turbulence was getting worse.

Seconds later, Lobach called out, “We’re at three hundred.”

Eaves replied that it looked to him like they were at 400 feet, not 300.[1:362] The reason for this discrepancy is unclear. No evidence was found to suggest that the pilots’ barometric altimeters were showing different values, although there was, as it turns out, a difference between the radio altitude and the barometric altitude, due to the accumulated error sources discussed in Chapter 5, which caused the barometric altimeters on the accident helicopter to read about 100 feet too low. Since the Potomac is a tidewater river as far inland as the Chain Bridge, the surface of the river would have had an elevation of about zero feet,[1:118] meaning that the radio altimeter in that location would have provided an accurate elevation reading about 100 feet higher than the inaccurate barometric altimeter reading. If Eaves had looked at his radio altimeter, which was not the Army policy when flying this route, then this could have been the source of his 400 feet estimation. However, it’s also possible that Lobach called out 300 feet before actually reaching it; or that one pilot or the other misread the altimeter. Either way, no further discussion of the discrepancy took place.

Less than a minute later, Eaves said “Alright, there’s three hundred for two hundred,” indicating that they had, in his view, now reached 300 and should continue down to 200, the route ceiling downstream of the Memorial Bridge. Lobach initiated a shallow descent, and after 28 seconds, she called out, “Two hundred.” This time Eaves didn’t mention any discrepancy.[1:363–365]

As the helicopter passed low over the Arlington Memorial Bridge, Eaves hopped on the radio and reported, “PAT 25, Memorial,” which the tower acknowledged. Then, observing that Lobach was having difficulty staying on course with the increasing turbulence, he began coaching her more heavily, offering frequent statements such as “lots of right pedal, ma’am,” and “there we go now, we can make the turn.” In the back, we know that Sergeant O’Hara was keeping watch for obstacles and traffic because at 20:45 he called out a crane, which Lobach announced was no factor.[1:367–368]

Moments later, Eaves again observed that they had drifted a little bit high, as he commented, “You’re at three hundred feet, come down for me.”

“Yeah, go down to two hundred,” Lobach acknowledged.[1:368]

Most likely, Lobach was simply having a hard time maintaining altitude and heading while flying manually in a UH-60L amid gusty winds. It was the Army’s expectation that she would be able to maintain altitude within ±100 feet, so Eaves called out the deviation as it approached that threshold. Based on the testimony of other 12th Aviation Battalion pilots, they almost certainly had no idea that the 200 foot route ceiling afforded a maximum separation of only 75 feet from landing airliners, nor would they have known that their barometric altimeters, which were set to the correct setting, were nevertheless reading 100 feet too low.

Looking outside, Eaves called out another crane, which he declared was no factor. Lobach acknowledged, maneuvering the helicopter across the Tidal Basin toward the Washington Channel.

Then, at 20:46 and 2 seconds, the Local controller called and said, “PAT two five traffic just south of Wilson Bridge is a CRJ at one thousand two hundred feet circling for runway three three.”

Knowing that PAT 25 was going to proceed down Route 4, and knowing that flight 5342, the CRJ, was circling for runway 33, the Local controller intended to arrange for the two aircraft to maintain visual separation from each other, as he had done countless times before. But in the cockpit of the Blackhawk, the poor radio reception quality and static interference coincidentally masked the word “circling,” which was not heard on the helicopter’s cockpit voice recorder.[1:220]

At the NTSB hearings, Clark Allen testified that the transmission quality to and from Army and Air Force helicopters was notably worse than other helicopter operators in the area, which in his view might have been because the military operators used older equipment.[3–2:45:00] Call it yet another reason to sunset the Limas.

Nevertheless, Eaves immediately replied, “PAT 25 has the traffic in sight, request visual separation.”

“Visual separation approved,” the Local controller replied.[1:370]

Now, strictly speaking, this traffic alert did not contain all the required elements, as it omitted the CRJ’s heading and distance. However, it’s doubtful that these elements would have increased PAT 25’s situational awareness. At that time, flight 5342 had yet to fully break off from runway 1 to begin circling to runway 33, so any heading and azimuth the controller might have provided were about to become obsolete anyway. Instead, the real problem with this transmission was the assumption that visual separation between these two aircraft was appropriate in the first place.

At that point, flight 5342 would have appeared to the Army pilots as one point of light among five all lined up with runway 1 at distances ranging from 3 to 20 miles away. Due to the orientation of the helicopter at that time, Eaves would have had to look out his right side window to see them, and none of the airplanes would have been visible to Lobach at all. Furthermore, from their perspective it would have been impossible to tell which dot was the “CRJ just south of the Wilson Bridge,” especially while using NVGs, which would have made less brightly lit airplanes appear farther away than they actually were.[1:237–238] Therefore, there was no way for the crew to know at that point which aircraft they were supposed to be visually separating from, and Eaves should not have reported that he had the traffic in sight.

However, as I established in Chapter 4, it was common practice among military pilots to report traffic in sight without actually spotting it, in order to facilitate traffic flow and avoid having to hold near Hains Point. Normally this practice was only applied when the traffic was approaching runway 1 or 19, because pilots perceived minimal risk of colliding with these aircraft. However, there is plenty of reason to believe that the crew of PAT 25 did not appreciate that flight 5342 was going to circle to runway 33, and that they assumed it was approaching runway 1.

Because the word “circling” was dropped from the controller’s traffic advisory, the pilots had to infer, based on the mention of runway 33, what the traffic pattern for that runway would be. However, 12th Aviation Battalion pilots mostly had little to no knowledge of the typical traffic patterns at DCA and many had never previously encountered an airplane landing on that runway. Therefore, they would have had to actively recognize that runway 33, based on its runway number, should be oriented southeast to northwest, and that an aircraft approaching it should come from the southeast, which was currently to their right but would be to their left while heading down Route 4. This was entirely possible for them to do, but only if they took a few seconds to think about it.[1:236]

At that time, however, the pilots were quite occupied with the task of flying the helicopter. With her very low experience level, maintaining heading and airspeed while navigating visually at low altitude in gusty wind conditions under NVGs most likely required Lobach’s total concentration, leaving little or no mental capacity to devote to the traffic situation. At the same time, the traffic advisory came during a period of especially high workload for Eaves, too. Within the last 47 seconds he had made a position report to ATC, advised Lobach to apply more right pedal, told her to begin a turn, called out an altitude deviation, and identified an obstacle. Most likely, he was devoting extra attention to their flight path, speed, position, and altitude because he knew that Lobach was struggling with those tasks, leaving him with little spare capacity to look for traffic either.[1:238–239]

As for O’Hara, from his position in the left crew chief seat looking out the left side window, he almost certainly could not have seen flight 5342 at any point during the flight,[1:134] nor did he discuss the position of the CRJ.

When Eaves immediately reported the traffic in sight and requested visual separation, this was most likely a rote response issued without thinking too much about the traffic in question. Because the traffic was still south of the Wilson Bridge, about 7.5 miles from his position, he might have considered it a low priority, and he didn’t discuss it with the other crewmembers at all. At the same time, his prompt and casually confident reply likely reassured Lobach that she didn’t need to worry about the traffic either.[1:237]

Taking into account the speed of his response, the number of other tasks demanding his attention, the absence of the word “circling,” and the general lack of knowledge of DCA operations, the NTSB concluded that Eaves most likely assumed the traffic in question was approaching runway 1, despite the controller’s mention of runway 33, and/or identified a target that turned out not to be flight 5342.[1:238] The possibility of such a misunderstanding had always been present with DCA’s visual separation scheme, and this probably wasn’t the first time it had happened, but either way, it was another huge step on the path toward disaster.

Now happily reassured that PAT 25 had assumed responsibility for maintaining its own separation from flight 5342, the Local controller turned his attention to some of the many other aircraft demanding his services. He considered giving a traffic advisory to flight 5342 as a matter of best practice, but in the end he decided not to, mistakenly estimating that the CRJ would have already landed by the time PAT 25 crossed its flight path.[1:62]

Meanwhile on PAT 25, Eaves remarked, “He’s got ’em stacked up tonight,” presumably while glancing south toward the long chain of lights descending into DCA.

“Kinda busy,” Lobach agreed.

The pilots spent some time discussing how to handle a right quartering tailwind that had begun to develop, all while Lobach steered the helicopter to the right, heading south down the Washington Channel toward Hains Point and Route 4. As they did so, flight 5342 was just beginning its right turn to follow Interstate 295 outbound for the circle to runway 33.[1:4, 372]

At that moment, the two aircraft were 48 seconds away from crossing paths. According to the alerting logic in the ForeFlight app, this was the point at which the helicopter pilots’ iPads most likely would have generated a traffic alert regarding flight 5342, calling out, “Traffic, 12 o’clock, 2 miles, 500 feet above.”[1:145] Had the iPads been integrated with the pilots’ headsets, they would have received the alert, glanced at the location of the intruder, and almost certainly realized that the traffic was approaching runway 33. Unfortunately, that didn’t happen.

At that moment, the CRJ would have been directly ahead, right in the middle of the pilots’ field of view.[1:129–130] There are probably many universes in which they saw it, realized what was occurring, and stayed clear, but we live in the timeline where they didn’t. Spotting traffic is hard enough with the naked eye and becomes even harder with NVGs, especially when the traffic is close to the ground and heading almost directly toward the viewer. In this case, flight 5342 was also flying at low altitude in close proximity to numerous ground lights, including the brightly lit National Harbor, which would have made it even harder to discern that that particular blob of light was an aircraft, especially when the pilots were probably expecting the traffic to be farther to the right, on approach to runway 1.[1:154–255] So it’s easy to sit in an armchair and say they should have seen it, but pilots fail to see traffic all the time, even when they’re looking for it. In this case, the pilots hadn’t received an updated traffic advisory with the target’s azimuth and altitude, so their chances of spotting it during a traffic scan were fairly poor even before accounting for other complicating factors. This is the whole reason why the reliance on visual separation in this airspace was so dangerous.

◊◊◊

At 20:47 and 33 seconds, with the aircraft about 26 seconds from colliding, a visual and aural conflict alert was triggered in the control tower.[1:7] Suddenly, the two aircraft that the Local controller thought were no longer his problem became his problem again.

The Local controller later judged that his workload at that time was about a 4 on a scale from 1 to 5, indicating high traffic complexity. Thirteen minutes earlier, when he first reported feeling overwhelmed, he had been responsible for 10 aircraft, including five helicopters; this number temporarily reduced to 8, but had since increased again to 12 aircraft, including 5 helicopters, by the time the conflict alert sounded. Given that he had been overwhelmed dealing with 10 aircraft, he was almost certainly even more overworked while handling 12, to the point that his situational awareness would have been rather adversely affected.[1:223–224]

For those of us who are not air traffic controllers, it’s tempting to ask, “is 12 aircraft a lot?” But the answer is always going to be, “it depends.” A controller can easily manage more than 12 aircraft if they’re all jets cruising on high altitude airways over a large chunk of airspace, but 12 aircraft of mixed types flying at low altitude through an area just a few kilometers across is totally different. Therefore, a better way to think about the workload imposed by this traffic density would be in terms of transmissions per minute. During the three minutes from 20:45 to 20:48, the Local controller went from making 4.5 transmissions per minute to 7.7, or about one every 7.8 seconds.[1:63] Put another way, during the 18 minutes from 20:30 to 20:48, he was on average either speaking or listening to a transmission 49% of the time, but after 20:46 this figure increased to 60% of the time.[1:65] Since these numbers don’t account for time spent identifying the aircraft calling, deciding what instructions to give, or other similar tasks, it’s clear that this workload would have left the controller with relatively little time to monitor his radar display or look out the window to improve his overall situational awareness. This explains why he didn’t notice that PAT 25 and PSA flight 5342 were on a collision course until the conflict alert sounded.

If we look at the events in the 90 seconds leading up to the start of the conflict alert, we can see this burden more vividly. At 20:46:10, the Local controller finished approving PAT 25’s visual separation request, then immediately gave a traffic advisory to American Airlines flight 1630, which was waiting for takeoff. At 20:46:19, he was contacted simultaneously on the separate helicopter and airplane frequencies by MUSL 7, an Air Force helicopter; and American Airlines flight 472, which was on approach to runway 1. He told MUSL 7 to stand by, then instructed another aircraft, PSA flight 5307, to taxi off the runway at taxiway November to make way for the next landing airplane. He then cleared American Airlines flight 1630 to take off, and as he was doing so, at 20:46:45, a medical helicopter, AirCare 1, attempted unsuccessfully to call him on the helicopter frequency. At 20:46:58, he turned his attention back to MUSL 7 and approved their requested routing, after which, at 20:47:13, American 472 and AirCare 1 simultaneously attempted to call him again. He approved AirCare 1’s requested routing, and at 20:47:33, as the medical helicopter was reading the clearance back, the conflict alert sounded.[1:65]

Ideally, the Assistant Local controller could have recognized the conflict well before the alert ever went off. However, during the two minutes leading up to the collision, she was writing down information about the different helicopters in the airspace, which, while required, was a lower priority than monitoring the traffic situation during a period of high workload. The NTSB later concluded that directly monitoring traffic would have been a better use of her time.[1:292]

Furthermore, the burden on both the Local and Assistant Local controllers would have been reduced significantly if the Helicopter and Local control positions had been staffed separately. Projecting the traffic situation into the future becomes harder as workload increases, so a standalone Helicopter controller with half the workload of the Local controller almost certainly would have detected the conflict earlier, and would have been able to actively monitor PAT 25’s progress relative to flight 5342.[1:226–227]

Unfortunately, this didn’t occur because the Supervisor never recognized a need to de-combine the positions. In fact, he later said he didn’t even recall hearing the conflict alert, nor did he notice anything abnormal about the traffic situation before the accident, and in his interview he conveyed an incorrect estimate of the number of helicopters in DCA airspace at the time.[1:229] The increasing traffic, the lack of requested miles in trail, the elevated use of runway 33, the presence of multiple helicopters, the history of close calls in the area, and the nighttime conditions were all risk factors that should have weighed toward de-combining the positions. However, the Supervisor had no guidance that he could use to weigh these risk factors, nor did he appear to recognize that these factors were present.

The NTSB found that his lack of awareness could have been partly because he had worked the position too long without a break. A 1989 study showed that if a controller spends more than 90 minutes on a task, their ability to detect complex situations in a timely manner starts to reduce. Nevertheless, there was no strict break requirement for Supervisors or Controllers in Charge, and the Supervisor had been working that role for more than 2 hours straight at the time of the accident. Therefore, the NTSB concluded that the Supervisor’s own situational awareness may have been degraded by spending too long on position.[1:229–230]

Nevertheless, in the end the conflict alert served its purpose by drawing the Local controller’s attention to a problem that he otherwise would have been too busy to notice. So when he heard it go off, he glanced at his radar screen, saw that PAT 25 was still flying toward flight 5342, and transmitted, “PAT 25, do you have the CRJ in sight?” Then, without even stopping to wait for an answer, he said, “PAT 25, pass behind that CRJ.” The sound of rapid beeping was audible in the background as the conflict alert continued to blare.[1:375]

On board the helicopter, the two rapid-fire transmissions confused Eaves, who keyed his microphone for 0.8 seconds during the second transmission, intending to reply, before realizing that he was stepping on the controller. The radio in the helicopter couldn’t transmit and receive at the same time, so everything the controller said during those 0.8 seconds was blocked, and the crew only heard, “PAT 25 — CRJ.”[1:8]

At that moment the two aircraft were less than 1.5 nautical miles apart, with minimal vertical separation and a closing speed of 200 knots. In hindsight, the controller needed to exercise positive control over the situation to prevent a collision, but that isn’t what happened.

As you may recall from Chapter 4, when I say “positive control,” I mean telling one or both aircraft to make a specific maneuver, such as “climb immediately.” FAA procedures for conflict resolution required the Local controller to use that phraseology. Telling PAT 25 to “pass behind that CRJ” isn’t taking positive control because the instruction is non-specific; its execution is dependent on the pilot’s judgment of where the CRJ is located.

When two airplanes are converging despite one aircraft previously reporting the other in sight, that’s a sign that visual separation is not working. Despite this, the Local controller’s call to PAT 25 contained no new information that would help them locate and steer clear of the CRJ, such as its relative altitude, azimuth, and heading.[1:231] The controller also did not at any point issue either a traffic advisory or a safety alert to flight 5342, further increasing his reliance on the assumption that PAT 25 was indeed maintaining visual contact with the CRJ.[1:232]

If the crew of PAT 25 had heard the words “pass behind,” they might have received some hint that the CRJ was on a crossing path with them rather than inbound to runway 1, although personally I wonder if it might have just caused confusion. Regardless, when asked whether he had the CRJ in sight, Eaves unhesitatingly replied, “PAT 25 has uh — aircraft in sight, request visual separation.”

“Visual separation,” The Local controller acknowledged.[1:375]

This exchange failed to fulfill the primary obligation of an air traffic controller, which is to prevent aircraft from colliding. If a pilot reports that they have an aircraft in sight but nevertheless continues to fly directly toward that aircraft, then the conflict hasn’t been resolved and further action is needed. The controller’s responsibility to resolve conflicts certainly doesn’t absolve the pilots of their basic responsibility to maintain awareness of the surrounding traffic, but neither does the pilots’ responsibility absolve the controller of theirs. As I mentioned in Chapter 4, many controllers at DCA didn’t appear to understand this.

The purpose of visual separation in a radar environment is to facilitate traffic flow by allowing aircraft to fly more efficient routes that take them closer than otherwise permitted to another aircraft that the pilot can visually confirm is not a threat. It’s useful in moderation, but when it becomes load-bearing, it turns into something it was never meant to be. It starts incentivizing controllers to put the aircraft out of mind to reduce workload, and it incentivizes pilots to request it in situations where separation from the traffic cannot be fully assured. The combination of these incentives is deadly because it causes controllers to rely on an overestimation of pilots’ actual knowledge of the traffic situation.[1:253–254]

As a result, when PAT 25 reaffirmed that they had the CRJ in sight, the Local controller was primed to accept that assertion over the judgment of his own eyes, which, had he looked at the radar display, would have shown him that the two aircraft were still on a collision course. Instead, he immediately turned his attention away, and after pausing for a few seconds, he received and answered a third attempted radio call from American Airlines flight 472.

In their final report, the NTSB noted that the controller had limited time and mental capacity to devote to solving the conflict, given his very high workload. This contributed to his failure to implement an effective solution. Risk mitigation while under time and workload pressure can be facilitated by threat and error management training, or TEM, which teaches controllers and pilots alike to quickly identify threats, recognize patterns that lead to adverse outcomes, and draw on previously learned problem solving strategies, making initial threat recognition and response effectively automatic. TEM is typically taught using scenario-based training designed to reflect actual threats that the controller or pilot is likely to encounter on the job.[1:209–212]

Following prior midair collisions involving light aircraft, the NTSB had recommended that the FAA provide scenario-based TEM training to air traffic controllers, including scenarios in which aircraft acknowledged visual separation but did not maneuver to avoid the traffic. The FAA partially agreed with the recommendation by promising to implement TEM training at its ATC academy, although it declined to use the suggested scenarios. But when the NTSB interviewed DCA tower personnel after the accident, they found that none of them were familiar with the term “threat and error management,” nor was there any evidence that they had received the training.[1:234–235] If he had, the Local controller might have recognized a common accident precursor in PAT 25’s continued flight toward the traffic they had promised to maintain separation from.

I’m not exaggerating when I say that this is a common accident precursor. In America’s deadliest midair collision, involving PSA flight 182 (a different PSA!) and a light aircraft over San Diego in 1978, the PSA crew reported that they were maintaining visual separation from the light aircraft, but failed to inform ATC when they lost sight of it. A conflict alert sounded in the approach control facility as the two aircraft approached one another, but the controller took no action to prevent the collision because he believed the PSA pilots were still maintaining visual separation. Sound familiar? Forty-seven years had passed, but had anything changed?

◊◊◊

At this point, with the two aircraft less than 20 seconds from colliding, PAT 25 was cruising along at a radio altitude of 281 feet above the river. Based on the flight recorder data, cross-checked with the elevations of their previous landing sites, the pilots’ barometric altimeters were likely showing values between 180 and 200 feet, leading them to believe that they were adhering to the Route 4 ceiling.

They were also slightly to the right of the route centerline, about 600 to 700 feet from shore, but this was not unusual. Pilots at the 12th Aviation Battalion testified that they did not fly directly over the bank itself for obstacle clearance reasons, but still stayed near the eastern side of the river; exactly how far from shore was acceptable had not been defined in any FAA regulation or battalion procedure.[1:53–54] PAT 25 was perhaps slightly farther from shore than optimal, but based on my rough estimates of the size of the blue line used to depict the route on the route chart, PAT 25 was probably just inside the line at this time, so it’s very difficult to argue that they were not following the route as depicted.

Regardless, with the helicopter at ~80 feet above the route ceiling and slightly west of the route centerline, the tiny clearance between Route 4 and the runway 33 approach path was eroded to zero.

Nineteen seconds before impact, as they were turning inbound to final approach, the pilots of PSA flight 5342 heard their TCAS call out, “Traffic, traffic.” The system would have generated a resolution advisory too, but they were below the RA inhibit altitude of 900 feet. The CRJ wasn’t equipped with ADS-B In, so the traffic alert was all they were going to get.

PSA Airlines procedures didn’t require pilots to verbally call out a TA, and neither pilot did so. In general, pilots trust that air traffic controllers are ensuring separation from nearby aircraft unless they have been instructed to maintain visual separation. A TA on approach while under radar separation will normally cause a pilot to stay alert for traffic and monitor the radio, but they would never jump to the conclusion that the controller has placed them into a dangerous situation.[1:158] A TA is not always a sign of an unsafe condition; TAs are often generated during normal operations that happen to involve less separation than the alerting envelope.

FAA guidance in the event of a TA advised that pilots should attempt to see the traffic, coordinating those attempts to the extent that workload allows, but should not maneuver based on a TA alone.[1:146]

At the time of the TA, Captain Jonathan Campos likely didn’t have the spare capacity to search for the traffic because he was hand-flying the airplane while aligning visually with the runway. At the same time, First Officer Sam Lilley was quite busy monitoring the approach while watching an aircraft that had been cleared for takeoff on runway 1 and was at that moment crossing their path.

Simulator tests with actual flight crews found that between reducing airspeed, monitoring the descent profile, making course corrections, monitoring the instruments, and listening to ATC, all while flying at night in gusty wind conditions, pilots rated the workload at a 7 out of 10, indicating “Very little spare capacity and maintenance of effort in the primary task is in question.”[1:151–153] This was why pilots didn’t like to take the runway 33 approach if they could help it, and it also explains why the TA didn’t prompt any audible reaction from the crew of flight 5342. During the simulator tests, when pilots were told to respond to the TA by searching until they spotted the traffic, they found that it was difficult or impossible to keep the plane on the desired flight path. Many also focused on the departing flight on runway 1 or even assumed that the TA was related to that aircraft.[1:151–153] The fact that the traffic alert coincidentally ceased as the airplane dropped below the 400-foot inhibit altitude around the time the departing flight became airborne could also contribute to the latter misconception.

It is unknown whether First Officer Lilley glanced down at his TCAS display, spotted the target, and attempted to find it. Given the high workload, it’s quite likely that he did not. But even if he did, he would have been looking for a rather small aircraft against a background of intense city lighting that would have made the helicopter almost impossible to see. The Blackhawk did not begin to be framed against the black Potomac River until 10 seconds before impact, by which time Lilley most likely would have already concluded his unsuccessful search and returned his attention to the instruments.[1:246–247] With the aircraft in a left turn toward the runway, both pilots thereafter would have focused their attention ahead and to the left, rather than to the right, where the helicopter was coming from.

The NTSB also pointed out that even if Lilley did see the helicopter, the pilots were trained not to maneuver unless they received an RA. That rule doesn’t apply below the RA inhibit altitude, but most PSA pilots didn’t remember what the inhibit altitude was. This could have caused the crew to hesitate to act until it was too late even if they had seen the helicopter in time.[1:247]

At the same time, visibility studies showed that the crew of PAT 25 could have seen the CRJ at this point if they had looked to their left, although it was still in an area of low visual acuity with lots of background lighting to interfere with the NVGs. Furthermore, Eaves was most likely looking ahead and to the right toward the area of runway 1, where he thought the traffic was located; he was not expecting an airplane to approach from his left. The lack of required azimuth information in the controller’s second traffic callout eliminated an opportunity for him to realize his mistake.[1:239] As for the others, we’ve already established that Lobach likely had no spare capacity to search for traffic, and O’Hara’s view was blocked by the aircraft structure.

Following the radio exchange, Eaves must have wondered why the controller was bringing up the CRJ again; perhaps he became worried that they were doing something wrong. So at t-minus 6 seconds from disaster, he said, “Alright, kinda come left for me ma’am, I think that’s why he’s asking.” This indicated that he believed the controller was worried about their clearance from landing traffic on runway 1 due to their distance from the shoreline. “Coming to the left a bit” would make no sense if he was aware of the CRJ’s true position.[1:239]

In response, Lobach said, “Sure,” acknowledging the instruction.

“We’re kinda…” Eaves started to say.

“Okay, fine,” said Lobach.

“…Out towards the middle,” Eaves concluded.

Two seconds after Eaves’ instruction, Lobach put the helicopter into a slight left roll, directly toward the approaching CRJ. The helicopter’s radio altimeter put them at a height of 278 feet.

Some articles written after the crash accused Lobach of failing to respond to an order to make an evasive maneuver by not turning left fast enough. This is a completely indefensible misinterpretation of what happened, because Lobach indeed responded to the order within the normal human response timeframe, and the collision was by that point already certain. Nothing Lobach did in the final seconds was causal to the accident.[4–9:11:00]

Just 1.3 seconds before impact, the pilots of flight 5342 saw the helicopter coming. With a desperate shout, Captain Campos hauled back on his controls to climb away, but it was too late. At 20:47 and 59 seconds, the helicopter’s rotor blades sliced into the low-hanging left wing of the CRJ, enveloping both aircraft in a halo of flame. Four seconds later, the shattered wreckage slammed into the ink-black water, taking with it the lives of 67 people.

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Chapter 8: Systems Theory and the Blame Game

While I was working on this article, a well-known aviation journalist said to me that blaming the Potomac River midair collision on an interaction between complex systems is a copout that allows those responsible for the accident to walk free and prevents corrective actions from being taken. I think that couldn’t be further from the truth, and it’s worth stopping to analyze why.

Articles have been written blaming the crash on various individuals, but most of them point the finger at the crew of PAT 25. These authors argue that Captain Lobach had no business being in control of that aircraft, that she violated the intentions of the helicopter route chart by flying too high and too far to the west, and Chief Warrant Officer 2 Eaves was derelict in his duty by failing to take corrective action. They also argue that both pilots ignored air traffic controllers’ warnings and failed to properly scan for traffic, flying directly into an aircraft that was visible if they had bothered to look.

Some of these arguments represent a willful disregard for the actual evidence. The NTSB found that the altimeters they were expected to use were reading too low, and various factors reduced the probability of spotting the aircraft, highlighting the inherent fallibility of the see-and-avoid concept. Furthermore, while Lobach was clearly struggling to maintain altitude and heading due to her lack of recent experience and generally average to below average stick-and-rudder skills, at the time of the accident she was flying within the only plausible interpretation of the route’s non-existent lateral boundaries, and believed she was adhering to the route ceiling. In fact, if PAT 25 had flown at exactly 200 feet down the exact centerline of Route 4, they still would have passed no more than 100 feet beneath flight 5342, which would be considered a near miss of historic proportions. Therefore, those who argue that the deviations from the route altitude and centerline were causal to the accident implicitly accept that flying 100 feet under a landing airliner while adhering to the published chart is somehow acceptable. Such a stance is, however, obvious lunacy.

The NTSB did conclude that “the lack of effective pilot-applied visual separation by the helicopter crew” was a causal factor in the accident.[1:299] This is because Eaves most likely knew that he did not have the CRJ in sight, or at least did not know which aircraft in his field of view was the CRJ, when he requested visual separation. There is no question that this was an error of judgment, but it was not a unique one, and therein lies the catch. The man who made that error is no longer with us, but the risk remains because the problem wasn’t the man. He requested visual separation from traffic he couldn’t positively identify because he felt that it was expected of him.

The fact is that this accident was made inevitable by the design of the airspace and the procedures used within it. With only 75 feet of clearance between Route 4 and runway 33, even a helicopter crew who flew the route perfectly could have collided with an airliner due to the fleetwide 100-foot altimeter error. While this risk could have been mitigated by applying radar separation, controllers preferred to use visual separation in order to increase efficiency and reduce workload, even though this technique carries greater risk of human error due to the inherent limitations of visual acuity. Therefore, the NTSB concluded that the placement of Route 4 itself, the FAA’s failure to conduct required annual reviews of the helicopter routes, and an overreliance on visual separation without considering the associated risks were all among the accident’s causal factors.[1:299]

Also causal to the accident, in the NTSB’s view, were the control tower’s lack of risk mitigation processes and the inappropriate combination of the Helicopter and Local control positions, which led to the tower crew’s loss of situational awareness and ineffective management of the conflict between PAT 25 and flight 5342. The NTSB also faulted the FAA for its failure to respond to warnings about the risk of a midair collision at DCA, and the Army for failing to ensure that its crews were aware of the Blackhawk’s barometric altimeter errors. Contributing factors included the limitations of the collision alerting systems in use; the “unsustainable” airport arrival rate, which placed an undue burden on controllers; the FAA’s failure to require ADS-B In technology; and the lack of effective sharing of safety data within the FAA and between the FAA and other stakeholders.[1:199]

However, I want to go beyond these conclusions to talk about two organizations that were called out in the NTSB’s findings — the FAA and the Department of Defense — and the pressures that were both imposed upon them and imposed by them upon others.

After the accident, the FAA responded to the dysfunction at the DCA control tower by reassigning several managers, which the NTSB called “inconsistent with the characteristics of a positive safety culture.”[1:283] This is because most of the shortcutting and risk-taking by ATC personnel was incentivized by a mismatch between the expectations placed on those personnel and the actual physical, human, and procedural resources available to them. ATC rules ineffectively constrained a drift in operating practices because the consequences of following the rules — such as widespread delays, frequent go-arounds, and inconvenience to thousands of people — were perceived as more undesirable than the consequences of breaking them. The FAA can’t solve this contradiction by reassigning personnel or updating policies. In its final report, the NTSB explained this same concept: “Organizational research has shown that policy or procedural changes alone are unlikely to produce durable effects,” they wrote, “unless they are accompanied by corresponding adjustments to authority, resources, workload allocation, and competing priorities that shape how work is actually performed.”[1:165]

At DCA, the need to maintain a high rate of traffic flow and the need to maintain a certain standard of aircraft separation were in active conflict, and the facility did not manage to find a balance between them that was acceptable to all stakeholders. In fact, Bryan Lehman of the Potomac TRACON said at the NTSB hearing that “Our ratio of safety to efficiency has gone slightly too far toward efficiency.”[4–7:26:10]

This struggle represents a microcosm of the FAA’s broader mission, which is to balance three impulses: safety, efficiency, and cost. Safety means minimizing loss of life and property; efficiency means ensuring that passengers and cargo can get where they want to go on time; and cost means ensuring that its actions taken to improve safety and efficiency don’t undermine the ability of commercial air carriers to maintain and expand their operations. Should any of these impulses be neglected, the others will also collapse: if the public believes it is unsafe to fly, efficiency will fall and costs will increase as more people avoid flying; if the system is inefficient, it becomes difficult to make money while upholding an adequate level of safety; and if costs for airlines are too high, they could cut corners to save money, compromising safety, or they could go out of business, limiting options for consumers.

When accomplished correctly, this balancing act reduces risk to the minimum level that can be achieved without overburdening the system as a whole. Obviously risk can only ever be zero if no airplanes are flying, because flight carries inherent risks. However, as the system evolves, new ways to further minimize risk become available, and the FAA implements new safety regulations that will achieve that progress at a price that is sustainable for the industry and for the FAA’s budget. However, the reality is that the FAA’s own funding has always been subject to the arbitrary will of elected officials whose interests must be accommodated if the agency doesn’t want to face cuts next time around.

For example, the FAA regularly takes the blame for the air traffic controller shortage, but did you know that a bipartisan plan to fund the creation of a second ATC training facility, removing one of the biggest bottlenecks in the system, was torpedoed because of politics? In 2024, a proposal to do just that was nixed after encountering opposition from Oklahoma lawmakers, who argued that a second facility might not be able to maintain the same quality standards as the existing facility in Oklahoma City.[43] For what it’s worth, I don’t see any merit to this argument; the more likely explanation is that the lawmakers were representing the interests of Oklahoma by perpetuating a system that currently forces most instructors and students to move to their state. (As a side note, I was told by a person in the know that Senator Ted Cruz also held up the proposal because he wanted the second facility to be in Texas; I have not yet seen documents that would officially confirm this.)

Similarly, Congress has forced the FAA to find ways to accommodate more flights to National Airport than the facility was designed to handle. I don’t need to reiterate why the number of slots is too high or how it contributed to the degradation of safety; I already did that in Chapters 2 and 4. What I want to focus on here is this political pressure as a fourth impulse that is outside the FAA’s ability to regulate. In my view, the primary reason that, as Lehman put it, the “ratio of safety to efficiency” went “too far toward efficiency” is because Congress was stepping on the scales. If the FAA had the power to act unilaterally, then it would have responded to the problems at National Airport by reducing the number of flights to a level where the traffic could be accommodated efficiently without compromising safety. But it couldn’t do that because Congress was in the way. Instead, the FAA was told to “make it work,” and that pressure was passed on to the control tower, which made it work by using visual separation as a cheat code to avoid a collapse in efficiency without initially appreciating the extent to which safety was being sacrificed instead. Some of the controllers themselves recognized it, of course, but doing anything about it would have set off a string of dominos leading to a confrontation with Congress, and nobody who was high enough up the chain of command to recognize that fact wanted to risk it.

Political intervention in the FAA isn’t inherently bad; for example, over the years Congress has acted to cut through inefficient bureaucracy and advance safety measures that the FAA was taking too long to implement. In that case Congress is making a conscious decision that the FAA has not correctly balanced the three impulses and needs to put more focus on safety. But when the system is used as a tool to advance a personal political goal, such as when a senator holds up a funding bill in committee in order to secure a flight slot to their district, unintended consequences follow. And as elected officials, the only reckoning they can face is with their own voters, because scrutinizing the actions of Congress is not within the NTSB’s remit; as far as an executive branch agency like the NTSB is concerned, Congress dictates the Overton window of what may be investigated. As long as the number of flight slots is statutory (written by Congress) rather than regulatory (written by an executive branch agency), the NTSB has to treat it like it’s a law of physics, while the FAA gets all the blame for setting the arrival rate too high.

Now, to be clear, I’m not saying that the FAA doesn’t bear any responsibility, or that the agency should just throw up its hands and say “nothing I can do.” There’s a lot that it can do and is doing to improve safety at DCA and throughout the national airspace system, but there are also some things it can’t control, and those influences played a key role in creating the circumstances for this accident to occur.

The other outside influence that I want to talk about came from the Department of Defense. I’ve already discussed how the helicopter routes were probably drawn up by the DoD, and how efforts to move them were blocked due to “continuity of government” interests. I’ve also talked about internal issues within Army Aviation and the Army more broadly that contributed to the accident, or at least made it more likely. And one thing the FAA can’t do is tell the military that it can’t use certain airspace, even though Army training and experience standards, aircraft certification standards, and safety systems might not meet the bare minimum required by civilian regulations.

But perhaps most dangerous is the DoD’s attitude toward the civilian aviation world. The US Army did not appear to even consider whether its operating practices put civilian air traffic in danger, a fact that the NTSB highlighted in its report, where they wrote, “The Army must take extraordinary care that it does not routinely introduce unacceptable risk to civil aircraft operations.”[1:285] The prevailing attitude within the military is that these kinds of considerations are wholly subordinate to the mission. At the NTSB hearings, the head of the 12th Aviation Battalion testified that in the unit’s risk management process, security ranks above safety — which should be unsurprising, because a military’s purpose is to enforce a country’s security interests first and foremost. However, it’s possible to take this concept too far, applying it to scenarios where major safety risks are introduced for minimal security benefit. For instance, the use of ADS-B Out during a training flight was considered a risk under the battalion’s risk management system due to the security risk of a crew accidentally revealing the locations of mission sites (which are mostly not secret, by the way; I mentioned the locations of two of them in this article and I didn’t break any laws to find that information).[3–3:56:00] Pilots were actually forbidden from turning ADS-B on mid-flight, preventing them from using it while passing through the class B airspace, even though this wouldn’t compromise mission security at all.[1:39] This had no impact on the accident, but it was representative of the Army’s mentality.

Near misses involving the US military’s lack of care toward civilian airspace have only continued. In December 2025, multiple aircraft reported experiencing losses of separation with large military transport aircraft over the Caribbean Sea during tensions with Venezuela; in each case the civilian aircraft received no TCAS alert because the military plane was operating with its transponder turned off. “We almost had a midair collision up here,” one JetBlue pilot ranted to air traffic control. “They passed directly in our flight path. … They don’t have their transponder turned on, it’s outrageous. We just had traffic pass directly in front of us within five miles of us — maybe two or three miles — but it was an air-to air-refueler from the United States Air Force and he was at our altitude. We had to stop our climb.”[44] The incidents spawned debate about whether the rather low security risk in the region was being weighed too heavily against the risk of crossing civilian airspace without a transponder. After all, if the security risk was really high enough to require that level of secrecy, why were commercial airplanes allowed in the airspace at all?

However, incidents raising questions about military attitudes are not confined to conflict zones; for instance, in recent months there has been an alarming series of low flyby events by military aircraft in violation of FAA minimum altitudes and without FAA approval. In the most recent event, a Blue Angels F/A-18 Super Hornet flew extremely low over a crowd of beachgoers in Pensacola, Florida during a practice demonstration, coming close enough to strafe civilians with heavy jet blast; had the maneuver been miscalculated even slightly, dozens could have been killed. The FAA stated that they had not issued a waiver permitting the Blue Angels to violate the 500 foot minimum altitude over a populated area.[45] The commander of the Blue Angels called the maneuver “unsafe,” and the pilot was reportedly mortified by their error. Nevertheless, senior civilian military leaders celebrated the incident.[46] The Secretary of the Navy posted, “No reprimands. No firings. No problem. That’s the sound of Freedom! Semper fi and Hooyah;”[45] a Defense Department account wrote, “Carry on, patriots;” the Secretary of Defense wrote, “The flyovers will continue until morale improves;”[47] and the White House posted, in response to criticism of the flyby, “It’s okay to love America.”[46] These statements follow an increasing pattern of civilian military leaders praising, encouraging, and even quashing investigations into potentially unsafe acts and regulatory violations by military pilots.[45][46] If this pattern continues, it will inculcate an even deeper disrespect for the Federal Aviation Regulations among military personnel, and the FAA will effectively lose control over military traffic within the National Airspace System.[45] Furthermore, such attitudes risk turning support for aviation safety into a political statement, which would be catastrophic.

This cultural issue within the US military represents another factor that makes it more difficult for the FAA to balance the three impulses, by introducing a highly random negative safety impulse that the agency is unable to control. To a large extent this is also a political impulse, albeit one that uses the military as an instrument rather than acting on the FAA directly.

If the status quo persists, the US military is likely to resist efforts to make it more accountable for the safety of civilians during peacetime, which could lead to the development of more unsafe practices in the name of national security. In fact, this is already beginning to happen, as we will see in Chapter 9.

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Political pressure on the FAA will always exist because it’s a government agency. However, if we want to prevent political interference from making the system less safe, we have to acknowledge its presence and recognize its harmful effects. I don’t mean to suggest that politics alone caused the disaster at DCA; in fact, far from it, but they did help create the circumstances for it to occur. A certain level of FAA cowardice or incompetence is also evident, as is the US Army’s blind ignorance, and a few split-second mistakes of judgment by people who were there that night and are now mostly dead.

The web of events that conspired for this accident to occur was composed of a large number of discrete and continuous elements, giving it the appearance of improbability, but each of those elements was individually commonplace, requiring only the right alignment in space and time. It was like brute-forcing a combination lock, testing the system over and over again until eventually the right combination was achieved. The probability that any one guess will turn out to be the right combination is tiny, but the probability that 1 million guesses will contain the combination is 100%.

The goal of all stakeholders now isn’t just to increase the amount of numbers in the combination; it’s also to stop making so many guesses. That requires buy-in from the FAA, the US Army, and the United States Congress. The final chapter in this story is about what they’re doing to break the cycle — and what they’re not doing.

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Chapter 9: Breaking the Wheel

If you’ve made it this far, you’ve probably lost count of the number of safety deficiencies that led up to this accident. The NTSB’s findings were sweeping and damning; hardly anyone escaped scrutiny and the need for improvement was universal. Some of those improvements are already taking place.

Aiming to reduce airport congestion, shortly after the accident the FAA conducted a review of the DCA arrival rates, which predictably concluded that the rates should be reduced. The arrival rates were then “temporarily” reduced by two across the board in the south configuration and six across the board in the north configuration.[1:74] As of this writing, these limits are still in place, but The Air Current reported in December 2025 that efforts to make them permanent had been stalled for some time.[26] If the FAA can avoid pressure to backslide on this issue, then this move might help reduce the strain on the system at DCA, but it will inevitably face scrutiny. Reducing the arrival rate lowers the number of aircraft that the airport can receive, meaning more flights will be forced to hold or divert. Eventually Congress may forget the lessons of the disaster and become annoyed by the increase in delays and cancellations, resulting in new pressure on the FAA to put things back the way they were before.

Early in its investigation, the NTSB recommended that the FAA prohibit use of helicopter Route 4 when runway 15/33 was in use, but on this matter the FAA went even further. Shortly after the accident the agency entirely abolished Route 4 from Hains Point to the Wilson Bridge without even waiting for a replacement route to be designated, leaving only narrow exceptions for “specific, limited operations,”[1:208] encompassing actual continuity of government missions, air ambulance flights with patients on board, and active law enforcement operations; furthermore, during those missions, runway 15/33 will be closed.[38] Route 6, which overflew the airport at 1,500 feet, was also removed. As a result, the NTSB classified its recommendation as “Closed — Exceeds Recommended Action,” which is extremely rare.[1:208–209]

In March 2025, the FAA began meeting with stakeholders to develop a replacement for Route 4 that would not interfere with DCA operations. So far, this has resulted in a number of significant safety changes to the Baltimore-Washington VFR Helicopter Route in addition to the removal of Routes 4 and 6, including modifications to zone boundaries and other helicopter routes to improve separation from airline traffic; introduction of labels and supplementary text identifying areas of elevated risk; and defined widths for some routes.[1:209] These changes are the first significant alterations to the chart since 1991.[1:46]

Across the National Airspace System, the FAA has begun using objective proximity data such as PDARS to identify areas of collision risk between fixed-wing aircraft and helicopters; assembling local task forces to implement changes to problematic routes; and implementing a mechanism to ensure that required annual reviews of helicopter route charts actually take place.[1:217–218] The FAA also announced its intention to create a Safety Integration Office to establish communication between different data collection and analysis centers and integrate their efforts into a comprehensive safety management system.[1:280]

In order to crack down on the dangerous overreliance on visual separation, the FAA prohibited visual separation within five miles of DCA and issued a nationwide order banning the use of visual separation whenever a helicopter is crossing the approach or departure path of a fixed-wing aircraft.[48]

In order to accommodate these changes without a major decrease in traffic flow efficiency, the FAA needed to accelerate the implementation of Time-Based Flow Management (TBFM) technology. Initially, this did not happen; in fact, documents show that in February 2025, days after the accident, the ongoing effort to implement TBFM was placed on hold “due to budget constraints and other program priorities.”[49] However, these priorities must have been revised at some point, because the NTSB later reported that the system became partially operational at DCA in October 2025 and was expected to become fully operational in March 2026;[1:79] I have not verified whether it met this deadline.

Despite these changes, some fundamental issues remain. While the DCA tower was not understaffed at the time of the accident, the staffing situation there has deteriorated since, with only 20 controllers and 3 supervisors available for duty out of an authorized 30 and 8, respectively, as of January 2026.[1:59] This crisis will ensure that the strain on DCA controllers only continues to increase despite positive changes to the airspace configuration and procedures. Controllers have also complained that the FAA has imposed rule changes and safety directives upon them without consultation, potentially creating new conflicts between the rules and the day-to-day job expectations, which is part of what caused the normalization of deviance at the facility in the first place.[1:187] If the job expectations themselves aren’t adjusted, no amount of rule changes will help, because controllers will feel pressure to improvise, especially as time passes and the accident fades from immediate memory. So far, traffic into DCA has not decreased, but the number of controllers has; this will complicate any effort to fix the tower’s safety culture over the medium to long term.

Some NTSB recommendations have yet to be acted upon. For instance, the NTSB wants the FAA to evaluate whether the Helicopter and Local control positions should use a common frequency when combined; no conclusion to this inquiry has been reached yet.[1:256] The NTSB also points out that FAA standards for VHF radio systems with anti-blocking technology, which either prevents simultaneous transmissions or notifies users when their transmission is stepped on, have existed since 1994. However only one anti-blocking radio has been certified by the FAA for aviation use and almost no aircraft or ATC facilities are equipped with the technology. Blocked transmissions played a significant role in the accident, and the NTSB recommended that the FAA act on this longstanding issue;[1:257] however, it will be many years before the technology becomes widespread even if the FAA acts quickly, which they might not.

The NTSB also recommended that conflict alerting systems in control towers should identify whether an alert has been generated due to proximity or projected aircraft trajectories, which would allow controllers to more quickly determine whether action is required; so far it’s unclear when or if this change will be implemented.[1:259]

On the Army side, some changes have taken place, but major issues remain unresolved. Some improvements have been made to the safety reporting system, such as segregation of aviation-related reports; however, the cultural issues surrounding reporting will take long-term sustained effort to resolve. The Army updated their UH-60 simulators to improve area familiarization training, and introduced procedures to ensure that ADS-B Out is functional on UH-60 helicopters;[1:218] meanwhile, Sikorsky distributed an all-operator letter describing the effect of the ESSS system on barometric altimeter readings, along with a correction table.[1:219] And in what is perhaps the most significant improvement of all, as of December 2025 the 12th Aviation Battalion was slated to sunset its UH-60Ls and switch to an all-UH-60M fleet by the end of 2026.[36]

The NTSB recognized that there’s a problem with radio reception on US Army aircraft, and recommended that the Department of Defense take action to correct the issue; however, it may be some time before anything comes of this.[1:236]

Fundamental issues related to Army pilot experience and aircraft utilization were not even addressed by any NTSB recommendations and will likely worsen as military fleets continue to age. It remains my impression, based on following economic and foreign policy-related news for many years, that America is losing its capability to develop next-generation combat platforms without massive cost overruns, cancellations, and serious production issues, before even accounting for the general loss of manufacturing capacity that has taken place over the last 20 years. If the United States can’t even build enough 155 millimeter artillery shells to replenish its own stockpiles, it’s not going to magically pull replacements for 50-year-old platforms out of thin air. And the older these aircraft get, the less time pilots will spend flying them, and the more risky the remaining flights will become. And while a replacement for the Blackhawk is slated to enter service a few years from now, it’s a needlessly complicated tiltrotor aircraft, so I can’t even imagine what kind of maintenance downtime it’s going to need when it’s as old as the Blackhawk!

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One of the most significant areas for improvement, or at least the one that got the most attention in the NTSB report, is the realm of collision alerting systems, including both ADS-B and TCAS. The latter is supposed to represent a last line of defense when other forms of separation have failed, but it failed to prevent this collision due to the inherent limitations of the system’s design. One of the major goals laid out by the NTSB was to push for this gap to be closed.

Testing based on the accident scenario showed that if flight 5342 had been equipped with ADS-B In, an ADS-B Traffic Advisory System, and a compatible cockpit display, it would have alerted the crew to the presence of PAT 25 twice during the 40 seconds prior to the first TCAS traffic alert, and the display would have provided considerably more detail about the location of the traffic. These alerts would have contained PAT 25’s azimuth and relative altitude, making it easier for the crew to spot the helicopter despite their high workload.[1:269–270] This system would have worked even though PAT 25 was not broadcasting ADS-B Out, because aircraft equipped with ADS-B In can display aircraft with transponders broadcasting Mode S, such as PAT 25, when in range of a ground station.[1:26]

It’s unacceptable to me that there has been so little progress toward incorporating systems with these capabilities into the flight decks of commercial airliners, while private pilots flying single-engine aircraft have had access to them for years. I understand that technology intended for Part 121 (scheduled commercial aviation) aircraft has to adhere to higher standards than Part 91 (general aviation), but if this becomes a barrier to adopting more capable systems, then we have a problem.

In its final report, the NTSB recommended that all aircraft operating in airspace where ADS-B Out is currently mandatory should be required to have ADS-B In as well. This is not the first time they’ve made such a recommendation and it might not be the last. After the accident, the deputy head of the FAA ATO stated that he supports an ADS-B In mandate, but it remains unclear whether this is official FAA policy.[1:216–217] Regardless, there remain significant technological barriers to bringing ADS-B In to every airline cockpit, and while the best time to start working to eliminate these barriers was 10 years ago, the second best time is now.

The NTSB also made a similar recommendation to the Department of Defense with regard to ADS-B In, but with the added stipulation that military aircraft equipped with ADS-B In should have a display configured to provide aural alerting that is actually audible to the flight crew.[1:272] This seems blatantly obvious, but hindsight is 20/20.

Of course, as I said in Chapter 4, the one capability that ADS-B systems lack is the ability to issue a resolution advisory. Flight 5342 never received one, but did it have to be that way? The NTSB sees great promise in an experimental technology called ACAS X that could fix some of the limitations of current traffic collision avoidance systems.

ACAS X, short for Airborne Collision Avoidance System X, is similar to TCAS except that it incorporates ADS-B traffic information directly, eliminating the need for two separate systems. Features of ACAS X that are absent from TCAS include lateral and speed-based resolution advisories; incorporation of ADS-B velocity vectors to determine threat level prior to issuing an alert; machine learning-based “probabilistic threat modeling;” and detailed traffic displays including arrows to show each target’s direction of travel.[1:34–35] It also produces 65% fewer alerts than TCAS, eliminating the majority of nuisance activations.[1:35] Testing showed that in the accident scenario, ACAS X would have issued a traffic alert to the crew of flight 5342 eight seconds earlier than TCAS did. However, at time of writing, the inhibit altitude for resolution advisories is the same for both TCAS and ACAS X. As a result, ACAS X, in its current form, wouldn’t have prevented the accident.[1:272–273]

The NTSB pointed out that there is no longer any technological limitation requiring such a high inhibit altitude. Individuals involved in the development of ACAS X testified that the reason the inhibit altitude hasn’t been lowered is due to legacy dependencies; for example, one aircraft manufacturer has an autoflight system that will automatically enact TCAS RAs, which would have to be reworked if the inhibit altitude was lowered.[5–1:50:00] However, these are not insurmountable challenges, and the benefits are significant. NTSB modeling found that if flight 5342 had been equipped with ACAS X with the inhibit altitude lowered to 300 feet, the crew would have received a timely resolution advisory, and the probability of a near miss or collision would have been reduced by 90%.[1:272–273]

At the same time, a version of ACAS X intended for helicopters, called ACAS Xr, is also in development. Because helicopters operate at low altitudes, ACAS Xr produces resolution advisories as low as 200 feet, and even with no modifications to the inhibit altitude, simulations showed that it would have reduced the probability of a near miss or collision by 50% had it been installed on PAT 25.[1:148] However, helicopters currently aren’t required to have any type of collision avoidance system at all, so deploying the system across the National Airspace System will require major rulemaking even after the technology becomes commercially available.

Unfortunately, there’s a long way to go before we start seeing ACAS X in widespread use. The design standards for ACAS Xr haven’t even been finished yet, and while standards for ACAS Xa — the airplane version — have existed since 2018, no equipment adhering to those standards had been deployed at the time of the accident. That’s partly because the European Aviation Safety Agency (EASA) didn’t recognize the ACAS X standard until March 2025.[1:35] Nobody was going to build an ACAS X module that couldn’t be sold in Europe, so this delay no doubt significantly impeded adoption of the technology.

Again, however, the second best time to start is now, so the NTSB recommended that the FAA require ACAS X on all new and existing airliners as soon as practicable, and require helicopters operating in Class B airspace to have ACAS Xr as soon as the design standards are finished and the system becomes available.[1:303]

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In total, the NTSB issued 52 recommendations as a result of its findings, spanning almost every topic I’ve touched on in this article, and some that I haven’t. Only a small number of these, most of which I’ve mentioned over the course of this Chapter, have been implemented to date. Some are in progress; the fates of others are unclear. A sustained effort by the families of the 67 victims has pressured Congress to act, and so far this effort has resulted in two sweeping bills, the ROTOR Act and the ALERT Act; however, neither of these has become law as of July 2026.

In the fall of 2025, work began to draft and pass the ROTOR Act, which was primarily aimed at implementing ADS-B In and Out requirements for civilian and military aircraft in congested airspace.[50] At that time, it was widely expected that this technology would become mandatory within the next several years, and to that end the FAA had already hashed out a memorandum of understanding with the Department of Defense, under which military helicopters in DC airspace would broadcast ADS-B Out at all times.

However, in December 2025, language was inserted into the annual National Defense Authorization Act (NDAA), the must-pass bill specifying the budget the Department of Defense, that undermined this agreement.[51] The bill stated that military helicopters conducting training missions in specifically the Washington D.C. area need only “actively provide warning of the proximity of such aircraft to nearby commercial aircraft in a manner compatible with the traffic alert and collision avoidance system [TCAS] of such commercial aircraft.”[52] This section effectively removed any requirement for military helicopters to broadcast ADS-B Out in the D.C. area, because only a basic transponder signal is required for compatibility with TCAS; and furthermore, as the accident illustrated, TCAS is almost useless in preventing conflicts at low altitudes where helicopters in the D.C. region operate.[51] But the text went even farther than that, too, authorizing a waiver to even this inadequate requirement — effectively allowing military aircraft to fly completely dark through Washington, D.C. — if the secretary of any military department finds that the waiver is in the national security interest of the United States and completes an assessment of the risk to commercial aviation. The bill did not explain what this assessment would look like, did not impose any limits on what may be considered “in the national security interest,” and required only the assent of the Secretary of Transportation, with no input from the FAA, prior to issuance of a waiver.[52]

NTSB chair Jennifer Homendy harshly criticized the provision, calling it a “step backward” and a “whitewash.”[53] Nevertheless, the bill passed the House and Senate and became law because holding up the annual defense authorization act was not seen as an option.

In response to this backward step, the Senate amended the ROTOR Act, which already proposed to require ADS-B In by 2031, in order to close the loophole created by the NDAA. This amendment would have restricted exceptions to ADS-B Out requirements for military helicopters to “sensitive government missions,” a definition that would exclude “routine flights, non-classified flights, proficiency flights, or flights of Federal officials below the rank of Cabinet Member or the Chairman of the Joint Chiefs of Staff.” The bill also would have required military flights not broadcasting ADS-B out to notify air traffic control of this fact.[54]

The Senate fast-tracked the ROTOR Act by unanimous consent, after which the bill was sent to the House for approval. However, when the House attempted to fast-track the bill on February 24, 2026 with a simple roll call vote, bypassing the normal rules of debate,[50] the Pentagon withdrew its support, arguing that it would create “operational security risks affecting national defense activities.”[55] As a result, several lawmakers switched from supporting to opposing the bill, and the ROTOR Act unexpectedly fell one vote short of the two thirds majority required to pass under the fast-track procedure.[50] Technically, the bill was not dead and could have been resurrected via the normal, more laborious process, but instead the House decided to move forward with its own bill, called the ALERT Act, which is rather different from the ROTOR Act.

Instead of narrowly focusing on accelerating adoption of ADS-B In, the intention behind the ALERT Act is to force the FAA and the DoD to address every single NTSB recommendation.[50] Initially, the NTSB expressed opposition to the ALERT Act, publishing a list of points where it felt the bill fell short of the intent of its recommendations.[56] The House subsequently amended the bill to address these concerns, but one major gap remains.

The ALERT Act, to its credit, does a very long list of things, too many to describe them all here. It basically goes through the recommendations section of the NTSB report and directly mandates that the FAA or the DoD, whomever is concerned, implement the recommendation within a specified timeframe. Some of these mandates even force the FAA and DoD to address systemic safety culture issues. However, instead of directly mandating that all aircraft currently required to have ADS-B Out also have ADS-B In, it rolls the ADS-B In requirement into a mandate that all applicable airplanes and helicopters have ACAS Xa or ACAS Xr that uses ADS-B In technology by December 31, 2031. Furthermore, the act would permit military aircraft to operate without broadcasting ADS-B Out if doing so would “affect the operational security of Department of Defense aircraft or special missions,” and requires only a risk assessment by the secretary of a military department with the assent of the Secretary of Transportation prior to issuing such a waiver.[57] This is only a marginal improvement over the NDAA provision that sparked fury from the NTSB in December 2025.

These two aspects of the ALERT Act have sparked widespread concern among safety advocates. The requirement to install ACAS X by 2031 is problematic because the technology isn’t even commercially available yet and might not be ready for installation on existing fleets for years to come. As the deadline approaches, the aviation industry will likely request waivers to the requirement while they wait for the technology to become widely available. Because the requirement for ADS-B In is tied to ACAS X, these delays will also delay installation of ADS-B In, even though that technology is already available for many aircraft types.[55]

As a result of this shortcoming, as well as the weak restrictions on military flights without ADS-B, Senators Ted Cruz and Maria Cantwell of the Senate Transportation Committee called the ALERT Act inadequate and urged the House to pass the ROTOR Act instead or in addition to the ALERT Act.[55] Other Senators stand with them, including Jerry Moran, chairman of the Senate Commerce Subcommittee on Aviation, as well as the families of the crash victims.[58]

The ALERT Act passed the House on April 14, 2026 by a vote of 396 to 10; however, as of this writing, the bill has not yet been taken up by the Senate due to skepticism in that chamber. Negotiations over the text of the bill are ongoing between the House and the Senate, but it’s unclear when it will become law or what it will look like if it does.[50]

As long as this legislative quagmire persists — and perhaps forever, should the ALERT Act and/or ROTOR Act fail to pass — military helicopters will retain broad authority to fly through crowded Class B airspace without broadcasting ADS-B Out and possibly without a transponder enabled at all. The military wants this capability because it views the perceived national security benefits as more important than the risks the practice poses to commercial aviation. In light of the recent pattern of behavior by military aircraft in civilian airspace, and the unprecedented intervention of high officials to encourage this behavior, it’s my belief that the Pentagon doesn’t deserve the leeway that it demands. Congress must forcefully assert the authority of the FAA over civilian airspace during peacetime, or risk further midair collisions.

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Until legislation has been signed into law, its deadlines have been met, and enough years have passed to give us a long-term perspective, the story of the Potomac River midair collision will not be over. In 20 or 30 years we will know its true place among the great tragedies that have shaped aviation across the last twelve decades, including whether it becomes a seminal moment that reshapes flight safety in the United States, or whether it turns out to be but the first warning sign that a golden age we thought would last forever had in fact come to an end, becoming another casualty of American decline.

It would be one thing if nobody had anticipated the disaster. That would have made it a true Normal Accident in the spirit of Perrow, who saw such events as “unexpected, incomprehensible, uncontrollable and unavoidable.” But while the collision was undoubtedly the inevitable result of interactions between the complex systems in which the two aircraft were operating, so many pilots and air traffic controllers saw it coming that Perrow might disavow the comparison, even as I insist upon its relevance.

The dangers created by the interlocking web of commercial, military, and political interests surrounding National Airport were evident to those who had to work there every day, but higher officials found the courage to defy those interests only after 67 people were already dead.

In her addendum to the NTSB report, Chairwoman Homendy decried a “tombstone mentality,” in which bodies such as the FAA or Congress only take action after a tragedy has occurred instead of listening to prior warnings. This mentality is a natural extension of human psychology, which struggles to correctly weigh hypothetical or probabilistic costs against immediate, known costs; hence, a potential safety expense appears more reasonable in that mental calculation once people have already died and the cost of inaction is no longer hypothetical. Proactive safety changes are possible, but they will always be harder than reactive safety changes; it is unlikely to ever be otherwise. This is especially the case when correcting the problem requires focused, multi-level coordination between several organizations. At the public hearing, Homendy decried the fact that once frontline FAA personnel identify a safety risk, it takes 21 bureaucratic steps to implement a change, bogging down proactive efforts until a disaster forces improvements.[3–6:37:00] The ultimate goal of theoretical research into risk management in complex systems is to find practical solutions to intractable problems such as these, but they may never be fully solved.

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Away from the pages of NTSB reports and the writings of safety theorists, hundreds of people continue to live with the irreversible consequences of the failures that culminated on the 29th of January, 2025. First Officer Sam Lilley left behind a fiancée and a wedding date that brought emptiness and grief instead of optimism for a future they had planned to spend together.[38] Sixteen-year-old figure skater Spencer Lane, a prodigious talent who had only been skating for three years but had already won medals, perished alongside his mother, leaving behind his father and younger brother to pick up the pieces. The Han family suffered a nearly identical tragedy, losing both 13-year-old skater Jinna and her mother Jin Hee.[59][60] Maxim Naumov, only son of the 1994 World Champions Vadim Naumov and Evgenia Shishkova, was orphaned in an instant; already an award-winning figure skater himself, he had to learn all over again how to follow his dream without them.[61]

Today, a year and a half on from the tragedy, those who were left behind are still shaped by that horrible night. Sam Lilley’s father has become a traveling advocate for aviation safety. Other family members have stood in the halls of Congress to plead for action. Maxim Naumov has taken over the youth skating club once run by his parents, and in February 2026 he fulfilled the mission they had long shared, traveling to Milan to compete for the United States in the Winter Olympics, just days after earning the bronze medal in the US Figure Skating Championships. In his pocket he carried a picture of himself, aged three, standing between his smiling parents, who watched over him as he received a standing ovation at the Milano Figure Skating Arena. Delivering a heartfelt address to the cameras after the performance, he gave a piece of advice to all those who might follow in his footsteps: do things out of love instead of fear.

For those who waited that night for a text message that never came, those who sat refreshing FlightRadar for a flight that would never arrive, the struggle is not over, and neither is it over for those who have dedicated their lives to the shining ideal that such loss is unnecessary. Forces of inertia, disinterest, and even arrogance continue to resist their efforts, pushing us toward a more dangerous aviation system, one where might makes right, the rules don’t matter, safety is an inconvenience, and managing risk is someone else’s problem. The Pentagon still wants to fly dark helicopters through DC airspace; the FAA is cutting control tower staffing targets and forcing controllers to work more hours;[62] soon, I expect, politicians will work up the courage to once again demand more flight slots into DCA, citing magical numbers that bear no relationship to reality. These interests, if allowed to operate unchecked, will drive us into the gaping maw of another disaster. But heroes like NTSB investigators, the families of flight 5342, and unnamed, uncelebrated people within the FAA still fight to avoid that fate, and to them I say: godspeed, and may you do that good work not only out of fear for the future, but out of love for your fellow man.

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If you live in the United States, call your representative to urge them to pass the ROTOR Act or a modified ALERT Act. The legacy of flight 5342 may hinge on the outcome.

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A massive thank you to all my readers, and especially my supporters on Patreon, whose contributions are crucial to my ability to produce stories like this one. This essay required more than three months of non-stop work to research, write, and deliver; it was a significantly larger undertaking than my master’s thesis. If you give back for the content I freely distribute, my gratitude to you will be immense.

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