On Tuesday night, just 24 hours before a deadly collision between a military helicopter and a regional jet at Reagan National Airport, a different passenger jet coming in for a landing at the airport alerted the tower it had to abort. The reason: risk of possible collision with a helicopter.

A similar situation played out less than a week earlier, on Jan. 23, when a flight from Charlotte suddenly pulled out of its approach at National. The captain informed passengers that he was tracking a helicopter and needed to abort the landing.

“They had to circle back around because there was a helicopter in the flight path,” Richard Hart, a passenger returning from a business trip, recalled the pilot announcing. “At the time I found it odd. … Now I find it disturbingly tragic.”

The two scrubbed landings within a week illustrate the heightened danger posed by frequent military helicopter flights adjacent to the busy airport, which have been the source of close calls and worries about crashes for years.

The U.S. Army Black Hawk that crashed into an American Airlines regional jet Wednesday night and killed 64 people, as well as three Army crew members on the chopper, had been flying along the east bank of the Potomac River in a flight corridor designated for low-flying helicopters.

The narrow lane for helicopters keeps them away from jetliner flight paths in much of National’s airspace, but it intersects with the path of aircraft on the southeastern approach to Runway 33, which is where American Eagle Flight 5342 from Wichita was attempting to land Wednesday.

Frequent military training and other flights around the airport have prompted the Federal Aviation Administration to place an air traffic controller dedicated to helicopters in the National Airport tower to manage the hazards, a person who is familiar with tower operations said.

But staffing levels were “not normal” inside the tower at the time of Wednesday night’s accident, and no single controller was assigned to helicopter flights, according to an air traffic safety report described to The Washington Post. When the crash occurred around 8:50 p.m. Wednesday, the job of managing helicopters in the vicinity was being handled by a controller who was also managing other air traffic, said the person, who spoke on the condition of anonymity to discuss an ongoing investigation.

According to a 2023 report to Congress, 50 entities operated roughly 88,000 helicopter flights within 30 miles of the airport between 2017 and 2019, based on FAA data. The largest percentage were tied to the military, but others included flights by medical operations, state and local law enforcement, and federal agencies. Some experts in aircraft safety raised questions about procedures and helicopter flight patterns.

Jim Brauchle, an Air Force veteran who flew cargo planes and now represents plane crash victims as an attorney at Motley Rice, citing maps for aircraft in the area, said planes approaching Runway 33 fly north on the eastern side of the Potomac River, then bank left as they descend.

“That helicopter route goes right underneath the final approach,” he said. “I was kind of taken aback by that.” Even if airplane and helicopter pilots are doing everything right, he said, they “potentially only have separation of a couple hundred feet. Why is this routing so close together?”

Investigators are still trying to determine what led to the midair collision, which caused a fireball in the air and sent pieces of aircraft plunging into the icy Potomac River. After searching the river all night, officials said early Thursday morning they did not expect to find any survivors.

The crash is likely to be the deadliest in the Washington area since Air Florida Flight 90 struck the 14th Street Bridge just after takeoff from National Airport. Seventy-four of 79 passengers and crew members died in the crash on Jan. 13, 1982. Four motorists on the bridge were killed. Investigators said the crash was caused by a combination of pilot error and improper de-icing procedures amid a snowstorm and freezing temperatures.

Transportation Secretary Sean P. Duffy said early Thursday that after the FAA “studies what happened, we will take appropriate action, if necessary, to modify flight paths and permissions.”

Wednesday’s crash happened on a clear but windy night, after air traffic controllers directed the American pilots to land at one of the airport’s smaller runways, a shift to the east that put it closer to the Army helicopter approaching on that side of the river. It meant the helicopter’s route would cross the regional jet’s approach for landing on National’s Runway 33.

The special helicopter routes are designed to give the military access to various bases along the Potomac River, said Michael McCormick, an associate professor at Embry-Riddle Aeronautical University who specializes in air traffic control. According to a person familiar with operations at the airport, who spoke on the condition of anonymity because of the ongoing investigation, conflicts between helicopters and jets often occur but are resolved with the helicopter swerving away or by the airliner circling and attempting a new landing approach.

The helicopter routes are meant to help “create as much certainty as you can in a three-dimensional safety environment,” said a former FAA official, who spoke on the condition of anonymity to discuss sensitive issues relating to the crash. “They want you as far to the east, and as far away from the approach path, as possible,” the former official said.

But questions have also been raised about whether there may also be structural problems at play — whether helicopter traffic over the Potomac is kept far enough away from the commercial planes coming in over the river so they can land on National’s Runway 33. A 2021 report by the Government Accountability Office noted that “in airspace near Reagan National and the Potomac River, FAA further limits the maximum altitudes for helicopters where helicopter routes overlap with commercial passenger airplane operations to ensure the safety of all aircraft.”

Wednesday night, air traffic controllers were in communication with the military helicopter, with a pilot confirming he could see the airliner and would avoid it, according to radio communications archived by LiveATC.net. That would be enough for air traffic controllers to be confident the situation was being handled safely, said Scott Dunham, a retired National Transportation Safety Board investigator.

Some, however, have theorized that the helicopter pilot could have confused the plane the tower was referring to with another aircraft in the area. Craig Alia, a retired Black Hawk pilot, said that on a clear night like Wednesday, the helicopter crew would have had good visibility. But he said the combination of city lights and busy skies can make it hard for pilots to understand the traffic patterns around them.

“When you get in that area, there’s a lot of congestion. A lot of times when you get a warning of an aircraft, you’re trying to figure out which aircraft,” said Alia, who is now the deputy commandant of cadets at Virginia Tech.

On Tuesday night, the evening before the fatal crash, the pilot of Republic Airways Flight 4514 from Connecticut told the National Airport traffic controllers that it had to divert. “We had an RA with a helicopter traffic below us,” said a female voice in the cockpit, according to the audio recording of air traffic control traffic.

“RA” is the code for the automated emergency alert that pilots receive when their aircraft is at risk of collision with another nearby aircraft, known as a resolution advisory. The twin-jet Embraer ERJ 175 was heading south along the Potomac River corridor toward its planned landing at National at the time, flight tracker maps show. Just as the aircraft neared Arlington Memorial Bridge, however, a male voice in the cockpit alerted the tower they would have to “go around.”

The plane took a sharp turn to the west, according to flight tracker maps of the aircraft’s path that night, and later landed safely at National at 8:16 p.m. A spokesperson for Republic Airways said the company was reviewing The Post’s questions and the details of the incident and could not immediately comment.

American Airlines did not respond to questions about Hart’s account of the diversion of its jet from Charlotte on Jan. 23, after the plane encountered a helicopter. Hart, who works in real estate and lives in Rockville, Maryland, frequently takes regional jets in and out of National.

“I’m on those jets all the time, so it hits home,” he said. “This was what was happening to us, though we didn’t crash, thank God. It’s terrible.”

Daniel Gilbert contributed to this report.

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