New information from the NTSB explains how the March 2026 LaGuardia runway collision between an Air Canada CRJ-900 and a fire truck happened.
On the night of 22 March 2026, something went very wrong at New York’s LaGuardia Airport (LGA).
A routine arrival from Montréal–Trudeau International Airport (YUL) ended in a deadly runway collision between an Air Canada Express regional jet and an airport fire truck. The National Transportation Safety Board’s preliminary report now provides the first detailed account of what happened in those final moments.
Although many questions remain, the initial findings are already prompting difficult questions.
A Landing That Never Finished
Jazz Aviation flight 646, operating as Air Canada Flight 8646, was on final approach to LGA’s Runway 4 just before midnight. The CRJ-900 had 76 people on board and was nearing the end of what had otherwise been a normal flight from YUL.
At 23:35:07 (all times local), the aircraft was cleared to land.
At the same time, multiple airport rescue vehicles were responding to a separate emergency near Terminal B. Seven ground vehicles began moving across the airfield, planning to cross Runway 4 via Taxiway D.
What happened next took place over the course of just a few seconds.
At 23:37:04, with the aircraft just a quarter mile from touchdown and about 130 feet above the ground, the lead fire truck, identified as Rescue 35, was cleared to cross the runway.
Three seconds later, the truck began moving.
Four seconds after that, the aircraft crossed the runway threshold.
The gap between them was closing fast.
“Stop! Stop! Stop!”
As the aircraft touched down, controllers took immediate action.
At 23:37:12, the tower instructed the fire truck to stop. Then again at 23:37:20.
Inside the truck, the crew sensed the urgency in the radio call but did not immediately understand what it meant.
One crew member later recalled hearing “stop stop stop” on the frequency, but not realizing right away that it was directed at them. Only after hearing “Truck 1 stop stop stop” did it fully register.
By then, the truck had already crossed the hold short line and was entering the runway at roughly 30 mph.
At the same moment, the aircraft was decelerating through about 100 knots, less than 400 feet from the intersection.
Two seconds later, they collided.
A System That Stayed Silent
LaGuardia is equipped with multiple layers of safety designed to prevent exactly this kind of scenario.
But in this case, several of them didn’t provide the protection you might expect.
The airport’s ASDE-X surface detection system, which is designed to track aircraft and vehicles and warn of potential conflicts, did not generate any alert in the tower.
Investigators say one key reason is that none of the responding ground vehicles were equipped with transponders. That meant the system could not reliably distinguish or track each vehicle, especially as they moved close together.
Instead of seven distinct vehicles, controllers saw only intermittent and merged radar targets.
Without a clear track for the fire truck, the system never recognized the developing conflict.
REL Lights Were On
Another layer of protection, however, did activate.
Runway Entrance Lights (RELs), designed to warn vehicles not to enter an active runway, illuminated as the aircraft approached.
Surveillance video shows the red lights were clearly on while the fire trucks were holding short, about 300 feet from the runway.
But those lights are designed to turn off as an aircraft passes an intersection.
In this case, they went dark about three seconds before the collision—just as the truck reached the runway edge.
That timing, by design, may have removed a final visual warning at the worst possible moment.
The Outcome Could Have Been Much Worse
The collision caused catastrophic damage to the forward section of the aircraft.
The cockpit area was destroyed, and both pilots were killed.
However, for passengers seated further back in the cabin, the outcome could have been much worse.
Passenger seats remained largely intact, and many occupants were able to evacuate through overwing exits. In total, 39 people were taken to hospitals, including six with serious injuries.
The aft flight attendant said the landing seemed normal until a sudden impact, followed by confusion and darkness, before passengers began evacuating.
Even with the confusion, most people evacuated in an orderly way.
The Investigation Continues
It’s important to remember that this is only a preliminary report. The NTSB has not yet determined a probable cause, and many details are still being analyzed.
But even at this early stage, some key issues are already becoming clear:
- A high workload environment, with controllers managing both arriving aircraft and a ground emergency
- Communication challenges, including blocked transmissions and delayed recognition of instructions
- Limitations in surface detection systems when ground vehicles are not fully equipped
- Safety systems that worked as designed, but may not have been enough in combination
None of these factors alone tells the full story.
But taken together, these factors help explain how a routine landing and a routine runway crossing ended up overlapping with tragic results.
As the investigation into Air Canada Flight 8646 continues, the focus will shift from understanding what happened to understanding why it happened. And perhaps, most importantly, preventing it from ever happening again.
The full preliminary NTSB report is below.
