Why ADS-B In must be Mandatory on the Flight Deck
By Capt. Ron Abel, MBA FRAeS — President & CEO, AbelWorks LLC
“This was 100% preventable.” — NTSB Chairwoman Jennifer Homendy, on the January 29, 2025 collision between PSA Airlines Flight 5342 and a U.S. Army Black Hawk helicopter over the Potomac River, which killed all 67 people aboard both aircraft.
Sixty-seven people died in an accident the National Transportation Safety Board determined was entirely preventable, using technology that was mature, standardized, and available on the date of the collision. The crew of Flight 5342 received their first TCAS warning 19 seconds before impact on approach to Runway 33 at Ronald Reagan Washington National Airport. A cockpit equipped with ADS-B In and an integrated Cockpit Display of Traffic Information (CDTI) would have given them 59 seconds. The NTSB is unambiguous that this difference was a matter of life and death. The Board is equally unambiguous about why that equipment was not there: its predecessor bodies and the Board itself had recommended, over more than two decades, that the FAA require aircraft to both broadcast and receive ADS-B signals. That recommendation was made and ignored 18 times.
The Asymmetry We Cannot Defend
Every commercial airliner operating in controlled U.S. airspace is now required to broadcast its position continuously under the ADS-B Out mandate that took effect January 1, 2020. Not one of those aircraft is required to receive the positions of surrounding traffic in the cockpit. Ground controllers receive a fused picture of radar and ADS-B data in near-real time. NAV CANADA and NATS receive North Atlantic position updates within seconds via space-based ADS-B. Airlines track their own fleets globally through operations center integrations. Members of the public follow flight movements on Flightradar24 from their personal devices.
The airline flight crew — the people legally responsible for the aircraft and for every life aboard it — are the last people in the ADS-B information chain, and in most airline cockpits today, they are not in that chain at all. This is simply unacceptable.
TCAS, the system the crew of Flight 5342 relied upon, issues Traffic Advisories that indicate only that a threat is nearby without specifying its precise position or vector, and its Resolution Advisories are automatically suppressed below 1,000 feet AGL — the exact altitude band where this accident occurred. Nineteen seconds was not enough time to identify the threat, confirm it, and execute a maneuver at low altitude on approach. Fifty-nine seconds is.
The Technology Is Ready
The argument that ADS-B In requires further development does not withstand scrutiny. The FAA’s ADS-B In Retrofit Spacing Initiative (AIRS) evaluated CDTI applications, including CDTI-Assisted Visual Separation and Initial Interval Management, in operational conditions, and standards for these applications are complete. American Airlines equipped a fleet of A321 aircraft with ADS-B In avionics in 2022 and conducted operational evaluations in enroute airspace. MITRE Corporation has produced a multi-purpose CDTI integrating 13 distinct functional capabilities within a single interface, designed without added crew workload burden. The ICAO Assembly’s 42nd Session has rightly identified ADS-B cybersecurity as a matter requiring systematic attention, and that work deserves our full support — but it is not a reason to delay the airborne display mandate that the safety record demands. The barrier here is not technical. It is regulatory will.
The Legislative Moment
The Rotorcraft Operations Transparency and Oversight Reform (ROTOR) Act, sponsored by Senators Ted Cruz and Tammy Duckworth, passed the United States Senate unanimously on December 17, 2025. It would require all aircraft equipped with ADS-B Out to carry ADS-B In with an integrated CDTI and audible alerting by December 31, 2031, and would require military and government operators to broadcast ADS-B Out in high-volume or high-risk airspace — closing the loophole that allowed a non-broadcasting Army helicopter to converge unseen on a commercial airliner in the airspace of the nation’s capital.
The House alternative, the ALERT Act, does not mandate ADS-B In with a CDTI. It relies on a rulemaking process that would delay meaningful action by years. ALPA, the Allied Pilots Association, the Association of Flight Attendants-CWA, and the NTSB have all identified this as falling short. ALPA President Captain Jason Ambrosi has stated the pilot community’s position clearly: any aircraft required to broadcast ADS-B Out must also carry ADS-B In integrated into the flight deck with audible alerting. That is not a union preference. It is a safety requirement, grounded in 20 years of deferred recommendations and 67 deaths over the Potomac.
Our window of opportunity is open now, but it will not remain open indefinitely. The House must amend the ALERT Act to include a specific, time-bound ADS-B In mandate with CDTI integration, and it must close the military loophole. These are not complex demands. They are the minimum that the evidence requires.
The Obligation We Cannot Defer
The case for mandating ADS-B In in airline cockpits is complete. We have the technology, the standards, the operational experience, the NTSB’s unambiguous findings, and the unanimous endorsement of the United States Senate. What we must now secure is the political and regulatory will to finish what the ADS-B Out mandate began.
Every aircraft required to broadcast must also be required to receive. Every operator that enters high-density or high-risk airspace must be required to broadcast. I am proud to stand with ALPA, IFALPA, the Allied Pilots Association, the Association of Flight Attendants-CWA, and the families who have advocated with courage and clarity throughout this process. The next preventable accident will be exactly that — preventable — and it will be on us if we fail to act. Jennifer Homendy was right: this was 100% preventable. We must ensure it is also the last time those words apply.
Capt. Ron Abel President & CEO, AbelWorks LLC Fellow of the Royal Aeronautical Society Former President, IFALPA