Key Insights Gleaned from the NTSB's Discussion on the DCA Mid-Air collision

Key Insights Gleaned from the NTSB's Discussion on the DCA Mid-Air collision

A tragic midair collision between an American Airlines regional jet and a U.S. Army Black Hawk helicopter near Ronald Reagan Washington National Airport on January 29 has raised concerns about the safety of helicopter routes near commercial airports and the accuracy of barometric altimeters in Army helicopters.

The National Transportation Safety Board (NTSB) is investigating the crash, which resulted in the death of 67 people, making it the deadliest U.S. aviation accident in decades. Transportation Secretary Sean Duffy has since permanently restricted nonessential helicopter operations around DCA and eliminated mixed traffic between helicopters and fixed-wing aircraft, both actions recommended by the NTSB.

FAA staff had previously warned about the Army helicopter route's proximity to commercial flights landing at the airport, but the agency did not act on these concerns. At DCA tower, one controller often handles helicopter traffic while another monitors fixed-wing aircraft. On the night of the accident, one controller was performing both roles, which is common at the airport.

NTSB Chairwoman Jennifer Homendy has suggested that the Black Hawk pilots may not have been aware of their altitude due to a malfunctioning barometric altimeter. Radar altimeters and barometric altimeters are different types of altitude measurement systems used in aircraft. The helicopter involved in the crash was on a training mission near the airport, operated by the 12th Aviation Battalion's Bravo Company, which runs training missions in the area related to priority air transport and continuity-of-government operations.

Investigations into a recent fatal crash revealed that the Black Hawk involved had an altimeter discrepancy where the barometric altimeter underreported the helicopter's altitude by about 80 to 100 feet compared to actual altitude. Tests of other Black Hawks in the same unit showed similar errors, with some helicopters having altimeter errors up to +/-200 feet.

This altitude inaccuracy likely contributed to the pilots' unawareness of their true height relative to a passenger jet, playing a role in the midair collision. The helicopters tested were older models lacking modern air data computers that improve altitude accuracy, relying on barometric altimeters that can show significant discrepancies.

To address this issue, the U.S. Army plans to inform all Army aviators about these known altimeter discrepancies by mid-September 2025, signaling a move toward raising awareness of potential errors in altitude readings. Additionally, there has been legislative interest in requiring all aircraft, including military ones, to transmit Automatic Dependent Surveillance-Broadcast (ADS-B) location data to improve situational awareness and safety, although military aircraft have exemptions for security reasons.

NTSB Chairwoman Jennifer Homendy criticized the FAA for not acting on the safety concerns of its employees, saying, "Sixty-seven people are dead! How do you explain that? Our bureaucratic process?" The FAA's acting deputy chief operating officer, Nick Fuller, stated that staffing at DCA was commensurate with other similarly sized facilities, despite a national shortage of air traffic controllers.

A working group at the airport had considered the possibility of moving or eliminating part of Route 4, but was unable to do so due to continuity of government operations or security concerns. Army representatives have stated that barometric altimeters can sometimes be off by a significant amount, and this may not necessarily be cause for alarm.

As the investigation into the midair collision continues, the NTSB has not provided any new information about the ongoing investigation. However, the problem of inaccurate barometric altimeters in Black Hawk helicopters has been acknowledged publicly, and measures such as pilot notification and legislative proposals for better tracking and altitude awareness are underway to mitigate this safety risk.

1. The National Transportation Safety Board (NTSB) is investigating the midair collision, with Chairwoman Jennifer Homendy suggesting that the Black Hawk's barometric altimeter may have malfunctioned.
2. Transportation Secretary Sean Duffy has taken action to restrict nonessential helicopter operations around DCA and eliminate mixed traffic between helicopters and fixed-wing aircraft.
3. The tragic collision has raised concerns about the safety of helicopter routes near commercial airports and the accuracy of barometric altimeters in Army helicopters.
4. A recent investigation into a fatal crash revealed that the Black Hawk's barometric altimeter underreported the helicopter's altitude by about 80 to 100 feet.
5. To address this issue, the U.S. Army plans to inform all Army aviators about known altimeter discrepancies by mid-September 2025, and there has been legislative interest in requiring all aircraft to transmit ADS-B location data.
6. NTSB Chairwoman Jennifer Homendy critically commented that the FAA should have acted on the safety concerns of its employees regarding the Army helicopter route's proximity to commercial flights.
7. As the investigation into the midair collision continues, measures such as pilot notification and legislative proposals for better tracking and altitude awareness are underway to mitigate this safety risk. Other aviation issues, such as general news, crime and justice, aviation, transportation, aerospace, finance, politics, policy-and-legislation, and war-and-conflicts, may also be discussed in related news stories.

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