Key takeaways from 3-day hearing on deadly D.C. midair collision

Over the course of three days of investigative hearings, the National Transportation and Safety Board sought to gather more information about the factors that lead to the deadly midair collision over Washington, D.C., in January between an Army helicopter and a passenger plane.

The NTSB heard testimony from air traffic controllers, the Federal Aviation Administration and the Army, and the families of several of the victims were in attendance. At one point on the first day of the hearings, NTSB Chairwoman Jennifer Homendy said of the circumstances leading up to the crash, "Every sign was there that there was a safety risk." Addressing the families, she said the hearings would be "a critical part of our ongoing investigation."

On Jan. 29, a Black Hawk helicopter struck an American Airlines flight from Wichita, Kansas, as it was coming in for a landing at Ronald Reagan National Airport, killing all 67 people aboard both aircraft.

The NTSB will continue its fact finding and will compile a final report with determinations about the probable cause, likely within the next year.

Here are the top takeaways from the hearings:

The barometric altimeter the Black Hawk crew members were relying on may have given them incorrect information, according to NTSB investigators, because the crew was calling out altitudes that were lower than the actual height at which the helicopter was flying.

The helicopter and commercial airliner collided approximately 300 feet above the Potomac River, and the maximum altitude for helicopters at that part of the route near D.C.'s Reagan Airport is 200 feet.

The NTSB, as part of its investigation, tested three helicopters that are in the same battalion as the one that crashed and found that the barometric altimeter for all three was off by 80 to 130 feet. Army representatives on Wednesday told investigators that discrepancy is within the accepted variability because pilots are trained to maintain their altitude at plus or minus 100 feet.

NTSB Chair Jennifer Homendy told CBS News' senior transportation correspondent Kris Van Cleave the NTSB calculated the margin of error on Route Four in that area of the Potomac to be 75 feet.

The Army said it is conducting additional reviews to determine how to proceed, frustrating investigators who asked why it would not make changes to the equipment, based on the findings of the NTSB tests.

In 2022, an FAA working group considered moving helicopter traffic away from the airport, but ultimately did not.

Transcripts from the airplane's cockpit voice recorder show the pilots received an automated verbal warning about traffic in the vicinity approximately 20 seconds before the collision. Less than two seconds before impact, the pilots shouted in alarm. Flight data indicates the plane's pilots attempted to climb to avoid the helicopter just before impact.

The transcripts also reveal the pilots of the American Airlines flight questioned the move to Runway 33. The plane was originally supposed to land on Runway 1 but was redirected by air traffic controllers to Runway 33. As it was trying to land on that runway, the helicopter and plane collided.

The pilots of the Black Hawk missed a key word when communicating with the air traffic control tower, according to a transcript released during the hearings of the conversation between the helicopter crew and the control tower.

Fifteen seconds before the collision, DCA Tower asked the helicopter if it had the regional jet in sight. Four seconds later, the DCA Tower instructed the helicopter to pass behind the plane. The Black Hawk's cockpit voice recorder indicated that the phrase "pass behind" was rendered inaudible because a helicopter crew member pressed the microphone key.

Although it was already known — based on control tower audio from that night — that the controller did not warn the American Airlines plane that the Black Hawk might cross its path, the FAA only openly acknowledged this for the first time during this week's hearings.

In a key moment from the second day, Homendy asked FAA Air Traffic Oversight Service executive director Nick Fuller if any traffic advisories or alerts were issued to the plane. He responded, "No safety alerts."

Homendy then asked, "Should the local controller have let the [plane] crew know that there was a helicopter there?"

"Yes," Fuller responded.

Rick Dressler, of Metro Aviation – which operates medical helicopters — was asked if there are units flying in the National Airport airspace that make him uncomfortable.

"I don't like saying that first heli of [U.S. Air Force] from Andrews (Air Base) and I don't like saying that 12th Aviation Battalion gives us all pause in the community…," Dressler said, but "we are all very uncomfortable when those two units are operating."

During the hearing, the Army admitted helicopters regularly flew below flights that land at Reagan National Airport.