NTSB Again Recommends Technology to Warn Pilots of Collision Risk
WASHINGTON (June 4, 2024) — Interruptions and multitasking led to distractions that caused the three-member flight crew of a B-777 airliner to mistakenly cross a runway occupied by another airplane taking off at John F. Kennedy International Airport in New York last year, the National Transportation Safety Board announced in an abstract published Tuesday.
In the evening hours of Jan. 13, 2023, air traffic controllers cleared a Delta Air Lines B-737 with 159 passengers and crew for takeoff on Runway 4L at JFK. Twenty seconds after the Delta 737 began its takeoff roll, an American Airlines B-777 destined for London’s Heathrow Airport with 149 passengers and crew crossed the same runway without a clearance.
As the Delta 737 accelerated down the runway, Airport Surface Detection Equipment – Model X, or ASDE-X, issued aural and visual alerts in the air traffic control tower, warning of a potential collision. Five seconds after the alerts, the controller cancelled the takeoff clearance of the Delta airplane, which quickly decelerated from its top speed of 121 mph as the American 777 was crossing in front of it.
In this incident, technology designed to prevent runway incursions alerted the air traffic controller of the danger of a collision, investigators said. The NTSB had recommended such technology in 1991, which led to the development of ASDE-X. The Federal Aviation Administration installed ASDE-X at JFK in 2009, one of just 35 major airports in the U.S. so equipped. The NTSB said additional risk mitigation strategies are needed to reduce the likelihood that flight crew surface navigation errors will result in runway incursions.
“The whole reason U.S. aviation has such an exemplary safety record is because we’ve built in extra layers of protection, which is why we need lifesaving technology at more of the nation’s airports,” said NTSB Chair Jennifer Homendy. “Our investigation also makes clear why we’ve long supported systems that warn flight crews of risks directly: because every second matters. Thankfully, the controllers acted quickly in this case, but safety shouldn’t be all on their shoulders. Instead, we must back up every single component of the system; direct crew alerts do just that.”
NTSB investigators cited numerous factors that contributed to the American Airlines captain’s mistake in continuing along the wrong taxiway and crossing the occupied runway without a clearance, including interruptions and multitasking that were happening on the flight deck during critical moments of ground navigation. The other two flight crewmembers didn’t catch the captain’s error because they were both engaged in tasks that diverted their visual attention from outside the airplane.
The investigation also identified safety issues with air traffic control.
The ground controller who provided the taxi instructions to the American B-777 crew didn’t notice the aircraft turned onto the wrong taxiway because he was performing a lesser priority task that involved looking down, the investigation found. The ATC tower team, which was involved with operations related to switching runways, also didn’t prioritize their duties to continuously scan the airport operations environment.
The NTSB made the following safety recommendations to the Federal Aviation Administration to address the risks identified in this investigation:
- Encourage flight crews to verbalize the number of the runway they are about to cross, unless an automated system already provides an advisory.
- Encourage air carriers to use their safety management systems to identify flight crew surface navigation errors and develop effective mitigation strategies.
- Evaluate the effectiveness of the activation logic for runway status light systems and update the logic as necessary to improve its effectiveness.
- Collaborate with aircraft and avionics manufacturers to develop a system that would alert flight crews of traffic on a runway or taxiway and traffic on approach to land and require that both newly manufactured and existing transport category airplanes have such a system installed.
- Updated a long-standing recommendation to require all airplanes be fitted with a cockpit voice recorder capable of recording the last 25 hours of audio.
Additionally, the NTSB once again called on the FAA to require all airplanes be fitted with a cockpit voice recorder capable of recording the last 25 hours of audio instead of the current standard of two hours.
CVR information was not available for this incident because the data were overwritten. As a result, the NTSB had to rely exclusively on flight crew recollections about the incident; however, these were not documented until a month after the incident occurred.
A cockpit voice recording would likely have provided additional details about the content and timing of crew communications, shed light on the crew’s minute-by-minute focus of attention, and revealed any unreported, non-pertinent conversations or other distractions.
The investigation abstract is available on the JFK investigation webpage. The final incident report will be published in several weeks.
The accident docket opened on Jan. 29, 2024.
To report an incident/accident or if you are a public safety agency, please call 1-844-373-9922 or 202-314-6290 to speak to a Watch Officer at the NTSB Response Operations Center (ROC) in Washington, DC (24/7).
