Federal investigators on Thursday detailed a series of issues and failures that led to the fatal collision between a regional jet and a fire truck at New York’s LaGuardia Airport last month.
According to a preliminary report by the National Transportation Safety Board, the truck drove through the airport’s version of a stop light and the vehicle lacked a transponder, which disrupted the crash warning system. There was also extra heavy air traffic and an emergency involving another plane at the time.
Regional Jet Air Canada Express Flight 8646 from Montreal with 76 people on board collided with a fire truck seconds after landing on March 22. Pilots Anthony Forrest, 30, and Mackenzie Gunther, 24, were killed, and 39 others were injured when the truck caught fire.
It was the first fatal 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 the night of the accident, in line with the normal schedule.
But LaGuardia was busier than usual because flight delays pushed the number of arrivals and departures after 10 a.m. to double than scheduled, according to aviation analytics firm Serium.
Planes were landing every few minutes in the lead up to the crash. At the same time, an emergency involving a strong odor on a departing United Airlines jet forced controllers to reschedule their duties. The fire truck involved in the crash was leading a convoy of emergency response vehicles.
While the more senior controller was coordinating the joint emergency response, the other controller took over directing the vehicles on the ground, continuing authorized takeoffs and landings.
“These controllers were very busy, very busy,” said aviation safety expert Jeff Guzzetti.
Fire trucks do not have transponders
LaGuardia is one of 35 major U.S. airports with an advanced surface surveillance system that combines radar data with information from transponders inside aircraft and ground vehicles to help prevent collisions. Controllers have a display in the tower that shows the location of every aircraft and vehicle.
The fire truck involved in the crash – and others in the convoy – were not equipped with transponders that would enable the system, known as ASDE-X, to precisely track their movements.
The system’s radar had trouble distinguishing fire trucks and other vehicles, and radar targets intermittently merged into the display. As a result, it does not sound an alarm to alert controllers.
The red light was on
According to air traffic control transmissions, the Air Canada flight was cleared to land at 11:35 p.m., about two minutes later, and 25 seconds before the crash, firefighters were asked to cross the same runway.
The flight was about 100 feet (30 m) above the ground when an air traffic controller cleared the fire truck to cross. At that time, there was a red light on the runway that served as a warning for crossing traffic.
They remained lit until the truck reached the end of the runway – three seconds before collision. By design, the lights turn off two or three seconds before the plane approaches the intersection of the runway, the report said.
According to former airline pilot John Cox, CEO of Safety Operating Systems, trucks should never enter a runway when the warning lights are on.
“That’s an automated system so even if the controller tells you it’s clear to cross, the lights mean there’s an airplane that’s either on the runway or about to,” Cox said.
Guzzetti said it may have been difficult 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 felt the plane and truck collide and told the fire crew: “Stop, stop, stop, stop. Truck 1. Stop, stop, stop, stop.”
The fire truck’s turret operator told investigators he heard “stop, stop, stop” but didn’t know who the words were intended for until he later heard “Truck 1.”
Then he saw that the truck had already entered the runway. When they turned left, he said he could see the lights of the plane on the runway.
It’s understandable that the driver didn’t realize the controller’s initial stop call was for a truck, Cox said, because he was directing several different vehicles in succession.
“Now we know who he’s talking to, but the first three stop, stop, stop there’s an ambiguity, if you’re listening to it, who he’s talking to,” Cox said.
But Cox said he’s not convinced that even if the driver had slammed on the brakes in the first call to stop the truck, he wouldn’t have been able to stop the truck in time, because the NTSB said it reached 29 mph (47 km/h) before it hit the runway.
Given the truck’s speed and weight, Cox said, the vehicle “won’t stop on a dime.”
