The first of the National Transportation Safety Board’s three days of investigative hearings is underway to help determine what caused the deadly midair collision on January 29 between an Army helicopter on a training mission and American Airlines flight 5342, operated by PSA Airlines, landing at Ronald Reagan Washington National Airport.
Transcripts of the cockpit voice recorders and air traffic control audio released in the docket for Wednesday’s hearing reveal what was said inside the aircraft in the moments before the crash.
As the passenger jet approached the airport, inside the helicopter the instructor was asking the pilot to descend.
“You’re at three hundred feet, come down for me,” the transcript from the cockpit voice recorder, also known as a black box, says.
Pilots on the regional jet performed their checks to land as the tower told the helicopter, call sign PAT 25, to look out for their CRJ-700 regional jet approaching at 1,200 feet.
“PAT 25 has the traffic in sight. Request visual separation,” the helicopter responds, asking for permission to avoid it visually.
In the helicopter the instructor says, “He’s got’em stacked up tonight,” according to the black box transcript.
The pilot responds, “Yeah kinda, busy.”
At 8:47 p.m., the controller asks the helicopter, “PAT 25, you have the CRJ in sight?” as the beeping of an alert the planes are getting too close together is heard in the background.
“PAT two five has uh – aircraft in sight. Request visual separation,” the helicopter responds.
Another instruction – to stay behind the passenger plane – wasn’t heard in the helicopter as a momentary press of the radio microphone in the Black Hawk cut it off.
Inside the helicopter, the instructor tells the pilot to change course.
“Alright kinda come left for me ma’am, I think that’s why he’s asking… We’re kinda… out towards the middle.”
“Oh-kay,” the helicopter pilot responds. “Fine.”
Not even a second later the recordings capture the sound of the collision and impact as the aircraft falls into the frigid river below.
Aircraft flown by PSA Airlines received collision avoidance alerts caused by helicopters five times in the five months prior to the crash, including one caused by two Black Hawk helicopters the day before the fatal collision, according to documents released in the NTSB docket.
The Traffic Alert and Collision Avoidance System, or TCAS, sounds an alarm in the cockpit if planes could be getting too close to each other.
On January 28, a PSA Airlines flight from Norfolk, Virginia, to Washington was leveling off at 3,000 feet when it received a warning due to two Black Hawks one to two miles away and 600 feet below it, the document shows.
PSA flights also received TCAS warnings caused by helicopters while landing at Reagan National Airport in September, October, and November.
The NTSB also presented for the first time major “discrepancies” in the altitude readouts on board the US Army Black Hawk helicopter that led to the crew believing they were flying lower over the Potomac River than they actually were.
Investigators said Wednesday that, following the crash, they tested three of the same models of Black Hawk helicopters from the same Army unit involved in the collision flying over the river.
“Notably, the barometric altimeters continued to be 80 to 130 feet lower than the helicopter’s determined altitude above sea level when flying at speed over the tidal portion of the Potomac River,” NTSB investigator Marie Moler presented to the hearing.
Barometric altimeters use pressure to gauge altitude and can be impacted by a variety of atmospheric and other factors.
In its preliminary report, the NTSB said the Black Hawk was consistently higher than maximum published altitudes along the Potomac River, including when it collided with the passenger jet.
The heavily technical findings were some of the the most significant in Wednesday’s 10-hour-long hearing.
The helicopter route at the time of the collision allowed the Black Hawk to fly as close as 75 feet below planes descending to land on runway 33 at Reagan National Airport, according to the NTSB. With allowable errors in the helicopter’s altimeters and other equipment as well as Army rules expecting aviators to hold their altitude within 100 feet, it could end up being much closer.
“How much tolerance should we have for aviation safety whenever civilian lives are at risk?” asked Todd Inman, NTSB board member. “How much is that tolerance,” he continued. “I think it should be zero.”
The Army responded that machines cannot be exact, but when dealing with such close altitudes the variables are concerning.
“We have to understand there are physical limitations to that, which is offhand plus or minus 100 feet,” Scott Rosengren, speaking on behalf of the Army, responded. “Knowing that there’s plus or minus 100 feet, any qualified Army pilot or any civil pilot will (think) the fact that we have less than 500-foot separation is a concern.”
The helicopter route has since been closed, but NTSB Chair Jennifer Homendy said she doesn’t believe “anyone did the math until the NTSB did the math” to determine how close planes and helicopters were getting until after the crash.
“My concern is, where else in the national airspace does that exist where there are charted helicopter routes?” she said.
Homendy also called on the Army to test the altimeters in all Black Hawks, not just a similar model to those involved in this crash.
The Army was also questioned about flying with the tracking system called automatic dependent surveillance-broadcast, or ADS-B, turned off.
ADS-B out broadcasts an aircraft’s location, altitude and other key factors to surrounding planes to prevent collisions, independent of ground-based controllers or radar.
Military helicopters still operate with their ADS-B tracking systems turned off “every day, including to this day,” in the Washington DC area, testified Rick Dressler, who works with medical helicopters for Metro Aviation in Washington, DC.
“It adds an unacceptable layer of complexity and risk to the system,” he said.
Colonel Andy Deforest of the US Army said the battalions view “the risk” to security as “paramount.”
He said the helicopter involved in the collision was following an Army policy to keep the technology turned off, in compliance with a memorandum of understanding between the Federal Aviation Administration and Department of Defense.
“The policy the day of the accident was to have ADS-B out off anytime you are conducting anything related to the mission, (for example) flying near a mission, route or location,” he said.
In March, the FAA committed to lawmakers that it would require nearly all aircraft near Reagan National Airport to have ADS-B turned on. Tuesday Sen. Ted Cruz proposed a bill that would require nearly all military aircraft in the US fly transmitting an ADS-B signal.
At the start of the hearing, an 11-minute animation was shown detailing the minutes leading up to the collision and a video of the accident itself. The board paused briefly to allow any of the family members of the victims of the crash to leave the room or look away before it was played.
The air traffic controller working in the control tower that night was responsible for two different positions on two different radio channels, the timeline animation revealed.
The captain of the regional jet had completed 106 flights into the airport and the first officer had completed 51, records reviewed by NTSB showed.
However, investigators said interviews with PSA Airline’s pilots showed they generally didn’t know much about the helicopter routes in the area. Three Reagan National Airport-based captains and one first officer were asked about their knowledge of published helicopter routes and only one PSA captain – who was a former military helicopter pilot in the region – had knowledge of the routes prior to the accident.
Sixty-seven people died in the accident over the Potomac River, including 60 passengers and four crew members on the plane and three soldiers on the helicopter.
“This is not an adversarial hearing,” Homendy said in her opening remarks. “This does not mean difficult questions won’t be asked. They will be, and they should be. This is an investigation. We are here to improve safety.”
The Army, PSA Airlines, the FAA and other parties are represented at the hearings. The NTSB will meet again Thursday and Friday. A determination of what caused the crash will come in January.
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