Overview
- The NTSB’s preliminary report released Thursday outlines how a controller cleared a Port Authority truck to cross Runway 4 just seconds before Air Canada Express Flight 8646 landed on March 22, then issued urgent “stop” calls that the truck crew did not immediately recognize as meant for them.
- ASDE-X, the tower’s surface-surveillance tool that fuses radar with transponder data, did not generate an alert because the fire truck lacked a transponder and several closely spaced vehicles merged on the display, limiting the system’s ability to track a conflict.
- Runway entrance lights that act as a red stop signal for crossing traffic remained on until about three seconds before impact, and experts note vehicles are expected to obey those lights even when a controller grants crossing clearance.
- Only two controllers were on duty as scheduled, with one juggling ground control and supervisory duties during an unrelated United Airlines odor incident and the other transmitting on both radio frequencies during heavier-than-normal late-night traffic.
- Pilots Capt. Antoine Forest and First Officer Mackenzie Gunther were killed and about 40 people were hospitalized, including two firefighters, as the jet was traveling about 104 mph; investigators made no causal finding, and the months-long probe could spur moves to equip emergency vehicles with transponders and to reassess tower workload and procedures at busy hubs.