On a fall afternoon, a Boeing passenger jet had just been cleared for takeoff at Reagan National Airport when the pilot saw a Bell helicopter lift off in a direction that would cross the plane’s path. The airplane pilot aborted the takeoff, overrunning the runway before coming to a stop on a grassy strip just 130 feet from the Potomac River.

It was Sept. 24, 1985. Although there were no injuries or damage to the plane, the incident triggered alarm over the coordination of helicopter and airplane traffic, and the adequacy of staffing and training of air traffic controllers.

“The circumstances of this incident exemplify safety issues regarding the general operation of helicopters at busy airports,” the National Transportation Safety Board wrote in a 1986 report.

The episode, which took place at a time when helicopter traffic was a “small percentage” of the airport’s traffic, shows how concerns over managing the congested airspace have stretched back decades before Wednesday night’s deadly collision of an American Airlines passenger jet and a Black Hawk helicopter.

The report from nearly 40 years ago brought into focus the importance of coordination between air traffic controllers. The passenger jet had been cleared for takeoff by the tower’s local controller, while the helicopter had received the go-ahead from another controller manning the helicopter position. The helicopter controller told investigators she hadn’t coordinated with the local controller because she didn’t expect the copter to cross into a flight path.

On Wednesday night, a single controller was monitoring both airplane and helicopter traffic, The Washington Post has reported, which presents a challenge during heavy air traffic. Two people were handling the jobs of four people inside the airport’s control tower at the time of the crash, according to an internal report. The cause of the crash remains under investigation by the National Transportation Safety Board, which has said tower operations will be among areas of scrutiny.

Robin Dillon-Merrill, a professor at Georgetown University who has studied near-collision aviation incidents, pointed to the abundance of such cases. “If the data is there, why don’t people do something about it?” she said, before answering her question.

The more people accomplish a risky maneuver successfully, she said, the less they worry. She summed up the attitude as: “We know that we can operate with less traffic controllers because we did it last week and we got away with it.”

Dillon-Merrill, who landed in a regional jet at National on Monday, predicted that government officials will now step in to improve the airport’s safety. “We had to lose lives for it to happen,” she said. “It’s so terribly, terribly, terribly sad.”

The Federal Aviation Administration did not respond to a request for comment.

Transportation Secretary Sean P. Duffy said Friday that helicopter access to airspace around the airport will be curtailed at least through the preliminary stages of the crash investigation. When certain exempt helicopter flights are permitted, such as emergency medical airlifts, airliner takeoffs and landings will be paused at the airport “to prevent potential conflicts in this airspace,” the FAA said in a published notice for pilots.

The FAA is aware that helicopter operators do not always follow prescribed routes and zones during flights, a practice that could compromise safety, according to a 2021 report by the Government Accountability Office. However, the agency does not track how often this may occur because of the technical challenges associated with conducting such an analysis, the report said.

The number of fully certified controllers at National’s air-control tower has fallen in recent years, with trainees making up more of its workforce, according to FAA records. The agency’s annual staffing plans show that the tower had 21 fully certified controllers on staff in 2019, before the onset of the COVID pandemic. That number rose to 24 in 2021 but had fallen to 19 by September of 2023, according to the records.

Meanwhile, the number of trainees at the tower climbed from three in 2019 to 10 in 2023. The total number of staff is in line with a target set collaboratively by the agency and the controllers union. But a 2023 audit by the Department of Transportation’s inspector general said the contributions of trainees are disputed. While they are certified, they are not able to perform all the jobs in the tower, according to the audit.

Nick Daniels, president of the National Air Traffic Controllers Association, said chronic understaffing is putting serious strains on the system — and it’s a problem that won’t be solved quickly.

“Right now, we have only 10,800 certified professional controllers doing this job every day, where we should have 14,335 doing it to staff the system,” he said. “A lot of that is overcome by controllers working six-day workweeks and 60 hours within that week, which leads to fatigue and exhaustion.”

The FAA has stepped up hiring, but even if the agency hires the maximum number of controllers each year, he said, it would take eight years for the system to catch up with today’s needs.

An expert panel the FAA convened in 2023 in response to a string of close calls said that air traffic controller shortages nationally led to fatigue and absenteeism. Typically the impact is flight delays, the experts said, but the shortages can also create risks.

“The combined effect of irregular operations necessitated by staff shortages erodes the margin of safety,” the experts reported.

Nationally, the combination of anti-collision technology, deft direction by controllers and vigilance by pilots has managed to orchestrate an exceptionally complex airborne ballet with very few fatal collisions. That has earned American aviation an exemplary safety record, cementing the notion for millions that getting on a plane is no more hazardous than driving — and statistically much safer. The last fatal U.S. airline crash was in 2009. A regional plane crashed near Buffalo, killing 50 people.

But a review of government reports and accounts by pilots and controllers reveals a steady drumbeat of concerns over the years at Reagan National Airport.

In November 2013, a National tower controller criticized the performance of a colleague after a helicopter came within a mile of a passenger plane, accusing the other controller of disregarding attempts to coordinate. “Our helicopter operation is an abomination of the picture of safe aircraft movement,” the tower controller wrote in an account submitted to the Aviation Safety Reporting System, a federal database of voluntary air-safety reports that haven’t been verified by regulators.

Less than two years later, an airplane captain complained that air traffic controllers at National were overly aggressive in trying to expedite traffic, noting how the busy airspace was complicated by military helicopters flying at a low altitude. “This is probably the most dangerous airport in the United States, strictly based on the fact that the controllers are pushing, pushing, pushing in an attempt to handle the traffic they have,” the pilot wrote in May 2015.

Two months later, a pilot complained that controllers gave a warning about a nearby helicopter only after the plane had maneuvered to avoid colliding with a helicopter at low altitude. “There was an extreme lack of communication between DCA Tower to [our flight] or DCA Tower to the associated helicopter,” the pilot wrote.

Air traffic controllers, for their part, have reported their own lapses.

In January 2016, a controller at National was handling traffic for both helicopters and airplanes and dealing with runways that were closed due to snow. “I had numerous helicopters in my airspace as well as a steady rate of arrivals and departures,” the controller wrote in a report. The controller failed to give traffic guidance to two helicopters, the report said, and was later told that one had to take evasive action to avoid colliding with the other.

In July 2018, a controller reported a failure to give traffic guidance to planes coming in for a landing after one pilot described seeing three helicopters close by. “I recommend recurrent helicopter training for the facility to prevent this incident from occurring in the future with other controllers,” the controller wrote.

Staffing has also surfaced as a concern, with controllers reporting on multiple occasions in recent years that they were simultaneously coordinating helicopter and airplane traffic. One such controller complained in September 2022 that after a certain point, “there isn’t enough staffing to fill all positions in the tower cab.”

As recently as April, a pilot faulted National’s air traffic control for not alerting the passenger plane to the presence of a helicopter about 300 feet below. “We never received a warning of the traffic,” the pilot wrote, “so we were unaware it was there.”

Michael Laris contributed to this report.

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