CNN —
A source familiar with the near-collision between two planes on a runway at John F. Kennedy International Airport told CNN that special flashing lights warning pilots not to taxi over a runway were actually working.
The new development further raises the possibility that human error contributed to Friday night’s incident.
The incident involved an American Airlines 777 improperly traversing an active runway at the busy airport. “Shit!” yelled an air traffic controller over the radio, urging a Delta Air Lines 737 to halt takeoff from the same runway on which the American plane crossed its direct path. The Delta plane stopped within 1,000 feet of the American jet.
On Wednesday, the source told CNN that airport staff “went out immediately” after the incident to confirm the runway status lights were working properly.
JFK is one of 20 airports in the United States equipped with the Federal Aviation Administration’s fully automated system that warns pilots “if it is unsafe to enter, cross, or take off from a runway.”
On Tuesday, the National Transportation Safety Board told CNN that “interviews are ongoing” as part of its investigation into the incident. The FAA is also investigating.
– CNN’s Gregory Wallace contributed to this report