(AP) — Long-standing concerns about military helicopters flying in crowded airspace and worries over short staffing among federal aviation workers emerged Thursday as key factors in investigators’ inquiry into the fatal midair crash between an Army helicopter and a commercial airliner earlier this year.

During the second of three days of witness testimony and public inquiry by the National Transportation Safety Board into the January midair crash over the Potomac River, the board focused on air traffic control.

The NTSB heard Thursday that it was common for pilots to ask to use visual separation — basically relying on their eyesight — just as the Army Black Hawk’s pilot agreed to do the night of the crash. FAA officials also said controllers relied heavily on pilots using visual separation as a way to manage the complex airspace with so many helicopters flying around Washington D.C.

But Rick Dressler, an official with medevac operator Metro Aviation, told the board it is difficult to identify other aircraft in the night sky around Ronald Reagan National Airport, especially if an onboard locator system was switched off, as Army choppers routinely did.

Dressler said that he and other civilian helicopter pilots have long been concerned about military helicopters flying around Reagan airport.

“I don’t like saying this. I’ll say it again on the record,” Dressler, a former Army aviator and retired Air Force officer, said. “I’m speaking for my group there. We we are all very uncomfortable when those two units are operating.”

The Department of Defense referred questions about Thursday’s testimony to the Army, who did not immediately respond.

The Air Force also did not immediately respond to questions about Dressler’s remarks.

The American Airlines jet arrived from Wichita, Kansas, carrying, among others, a group of elite young figure skaters, their parents and coaches, and four union steamfitters from the Washington area.

The collision was the nation’s deadliest plane crash since November 2001 and was the first in a string of crashes and near misses this year, despite statistics that still show flying remains the safest form of transportation.

It’s too early for the board to identify what exactly caused the crash. The board’s final report won’t be released until sometime next year.

Final moments on Black Hawk

Communications from on board the helicopter moments before the collision were released as part of the board’s investigation.

The Black Hawk’s crew had been communicating with the airport’s control tower, although the helicopter pilots did not fully hear the controller’s instructions.

The Black Hawk pilots told the tower twice in the minutes before the crash that they had the American Airlines passenger plane in sight and would maintain proper separation. But when the controller instructed the pilots to “pass behind” the jet, the crew didn’t hear that instruction because the Black Hawk’s microphone key was pressed at that moment.

Just before the collision an instructor pilot aboard the helicopter asked the pilot at the controls to come left. But it wasn’t clear if the pilot had time to maneuver the helicopter before the crash.

“Kinda come left for me ma’am,” the instructor said.

The pilot responded: “Sure.”

‘Be fully transparent’

Bryan Lehman, who has worked for the FAA for more than 35 years, said during Thursday’s hearings that the agency must do better at listening to safety concerns.

Lehman, who works at a regional radar facility that directs planes into the D.C. area, said he sent a detailed memo in 2023 urging the FAA to reduce flights coming in and out of Reagan airport. But Lehman said the issue was dropped.

At several points throughout the hearing, NTSB Chairwoman Jennifer Homendy reminded FAA and Army witnesses that they are covered by whistleblower protections and shouldn’t be disciplined for anything they say.

But just before lunch on Thursday, she ordered a change in seating arrangements after a supervisor elbowed an FAA employee in midsentence during testimony, prompting that person to stop speaking.

“We want people to be fully transparent and feel safe in providing us answers. So we’re going to switch the panelists. I’m not going to put up with that,” Homendy said.

‘Fix it’

On the first day of hearings Wednesday, investigators highlighted the warnings about helicopter traffic that the Federal Aviation Administration received years before the tragedy over the Potomac River.

Homendy urged the FAA to “Fix it. Do better” at the end of a fiery exchange when she highlighted the warnings the agency ignored years earlier. She also suggested the Army adopt a formal policy making it clear that helicopter pilots should never fly under landing planes because pilots told investigators they were doing that routinely.

“Every sign was there that there was a safety risk and the tower was telling you that,” Homendy said.

But there were 21 bureaucratic steps the tower had to follow to get a change made and after the accident the FAA transferred managers out of the tower instead of acknowledging that they had been warned.

“What you did is you transferred people out instead of taking ownership over the fact that everybody in FAA in the tower was saying there was a problem,” Homendy said. “But you guys are pointing out, ‘Welp, our bureaucratic process. Somebody should have brought it up at some other symposium.’ Are you kidding me? 67 people are dead. How do you explain that?”

FAA didn’t add warning to helicopter charts, official says

Homendy said an FAA working group raised concerns about all the helicopter traffic around Ronald Reagan National Airport and the risk of a collision in 2022, but the FAA refused to add a warning to helicopter charts urging pilots to use caution when this runway was in use.

“This is the very event that this would have been the cautionary note for,” she said.

Video and animation presented during the proceeding’s first day showed the helicopter flying above the 200 feet (61 meters) altitude limit before colliding with the plane.

Investigators said Wednesday the flight data recorder showed the helicopter was actually 80 feet to 100 feet (24 to 30 meters) higher than the barometric altimeter the pilots relied upon showed they were flying. So the NTSB conducted tests on three other helicopters from the same unit in a flight over the same area and found similar discrepancies in their altimeters.

Dan Cooper with Sikorsky helicopters said that when the Black Hawk helicopter involved in the crash was designed in the 1970s, it used a style of altimeter that was common at the time. Newer helicopters have newer air data computers that help provide more accurate altitude readings.

Army officials said a discrepancy of 70 to 100 feet (21 to 30 meters) between the Black Hawk’s altimeters is within the acceptable range because pilots are expected to maintain their altitude plus or minus 100 feet.

Concern about distances between planes and helicopters

John Cox, an aviation safety expert and retired airline pilot, said the hearings are headed in the right direction to determine what happened and to prevent similar accidents.

His main concerns focus on the Black Hawk helicopter, including why it was above the 200-feet (61 meters) elevation limit for that particular helicopter route. Another question is why the Black Hawk wasn’t closer to the east bank of the Potomac River, where it would have been further away from landing airplanes.

“I’ve passed helicopters underneath me over the east bank of the Potomac a lot of times,” said Cox, who flew commercial airliners for 25 years. “And there’s always been plenty of separation. It’s not a lot because the space is so constrained. But you’re dealing with professional pilots and it’s not been a problem.”

Investigators said Wednesday the flight data recorder showed the helicopter was actually 80 feet to 100 feet (24 to 30 meters) higher than the barometric altimeter the pilots relied upon showed they were flying.

Staffing worries

James Jarvis helped evaluate Reagan airport operations for several years. During a 2022 evaluation, he said the airport was so far out of compliance on more than 33 items that the audit was stopped to help the facility identify where to improve.

Jarvis said that he was concerned about staffing levels, particularly the lack of support staff who helped air traffic controllers focus on what they needed to. And he said controller staffing levels were always on the low side.

“At one point I was told to quit bringing it up,” said Jarvis who works for FAA contractor Leidos.

In response to Jarvis’ comments, the FAA said in a statement that it has “supercharged the air traffic controller hiring pipeline – shaving months off the process and incentivizing new recruits with bonuses, which resulted in the busiest July in FAA Academy’s history.”

Associated Press writers David Klepper, Mike Catalini, and Ben Finley contributed to this story.