Federal investigators on Thursday detailed a series of issues and failures that led up to last month’s deadly collision between a regional jet and a fire truck at New York’s LaGuardia Airport.
According to a preliminary report from the National Transportation Safety Board, the truck drove through the airport’s version of a stop light and the vehicle lacked a transponder, hampering a crash warning system. There was also extra heavy air traffic and an emergency involving another plane at the time.
Air Canada Express Flight 8646, a regional jet from Montreal with 76 people aboard, slammed into the fire truck seconds after landing on March 22. Pilots Antoine Forest, 30, and Mackenzie Gunther, 24, were killed, and 39 people were taken to hospitals with injuries, including the two people in the fire truck.
It was the first deadly crash at LaGuardia in 34 years. Here are some key takeaways from the NTSB’s report.
Busy air traffic controllers
Two air traffic controllers were on duty on the night of the crash, consistent with normal scheduling.
But LaGuardia was busier than usual because flight delays pushed the number of arrivals and departures after 10 p.m. to more than double what was scheduled, according to aviation analytics firm Cirium.
Planes were landing every few minutes in the lead up to the crash. At the same time, the controllers had to shuffle their duties because of an emergency involving a strong odor on a departing United Airlines jet. The fire truck involved in the collision was leading a convoy of vehicles responding to the emergency.
While the more senior controller was coordinating the United emergency response, the other controller took over directing vehicles on the ground while continuing to authorized takeoffs and landings.
“These controllers were just way busy, just too busy,” aviation safety expert Jeff Guzzetti said.
No transponder on the fire truck
LaGuardia is one of 35 major U.S. airports with an advanced surface surveillance system that combines radar data with information from transponders inside planes and ground vehicles to help prevent collisions. Controllers have a display in the tower that’s supposed to show the location of every plane and vehicle.
The fire truck involved in the crash – and the others in the convoy – were not equipped with transponders that would have enabled the system, known as ASDE-X, to precisely track their movements.
The system’s radar had trouble distinguishing the fire truck and the other vehicles, and the radar targets intermittently merged on the display. As a result, it didn’t sound an alarm to alert controllers.
Red lights were on
According to air traffic control transmissions, the Air Canada flight was cleared to land at 11:35 p.m. About two minutes later, 25 seconds before the crash, the fire crew asked to cross the same runway.
The flight was about 100 feet (30 meters) above the ground when an air traffic controller cleared the fire truck to cross. At the time, a system of red lights on the runway that act as a warning for crossing traffic were still lit up.
They remained illuminated until the truck reached the edge of the runway – about three seconds before the collision. By design, the lights turn off two or three seconds before a plane reaches a runway intersection, the report said.
The truck should have never entered the runway while the warning lights were on, even though the controller cleared it to cross, according to former airline pilot John Cox, CEO of Safety Operating Systems.
“That’s an automated system so even though the controller says you’re cleared to cross, the lights mean that there’s an airplane that is either on the runway or about to be,” Cox said.
Guzzetti said it may have been hard to see the runway lights before the crash because it was dark and the pavement was wet.
‘Stop, stop, stop’
Nine seconds before the crash, the controller realized the plane and truck were set to collide and told the fire crew: “Stop, stop, stop, stop. Truck 1. Stop, stop, stop, stop.”
The fire truck’s turret operator told investigators that he recalled hearing “stop, stop, stop” but didn’t know who the words were intended for until subsequently hearing “Truck 1.”
He then noticed the truck had already entered the runway. As they turned left, he said he could see the plane’s lights on the runway.
It’s understandable that the driver didn’t realize the controller’s initial stop call was meant for the truck, Cox said, since he was giving instructions to multiple different vehicles in succession.
“Now we know who he’s talking to, but the first three stop, stop, stop there is ambiguity, if you were listening to it, who he’s talking to,” Cox said.
But Cox said he’s not sure the truck would have been able to stop in time even if the driver had slammed on the brakes at the first call to stop, because the NTSB said it had reached 29 mph (47 kph) before it entered the runway.
Given the truck’s speed and weight, Cox said, the vehicle “isn’t going to stop on a dime.”
