An Air Canada regional jet landing at one of the country's busiest and most prominent airportsslammed into a fire truck at more than 100 miles per houron Sunday, leaving federal investigators and frightened passengers questioning what could have gone wrong.
The National Transportation Safety Board combed through wreckage, collecting data and physical evidence to find answers in the first days of an investigation that will take a year or longer.
"We have a lot of data right now, a lot of information, including information on tower staffing, but the NTSB deals in facts," said Jennifer Homendy, chair of the NTSB, at a news conference on Monday. "We don't speculate. We don't take one person at their word. We verify that information carefully before we provide it."
Investigators have released the plane to Air Canada, the airline said, which will move it into a secured hangar where teams will begin reuniting passengers with the personal belongings they left behind as they evacuated.
"Items will be safely returned as soon as possible, although the process of sorting and identifying all belongings from the aircraft will take time," the airline said Wednesday.
Air Canada Express flight 8646, operated by Jazz Aviation, had 72 passengers and four crew members on board for the flight from Montreal to New York's LaGuardia. The two pilots died and four of the dozens of passengers and crew who were injured in the collision remain in the hospital, the airline said.
The Transportation Safety Board of Canada, the airline and the Port Authority of New York and New Jersey, which runs the airport, will also participate as parties to the investigation.
The first several days of the investigation are going to be focused on data collection, according to Jim Brauchle, an attorney that represents plaintiffs in aviation disasters for the law firm Motley Rice.
"They won't be doing a lot of analysis the first few days," Brauchle said. "That's more facts and data collection and getting witness statements and those kind of things, while it's still fresh."
What happened in the tower?
Questions about the people in the control tower, their responsibilities, and if all proper procedures were followed will be answered in the course of the investigation.
Homendy confirmed Tuesday there were two controllers working in the tower cab, the top of the control tower which looks out over the airfield, at the time of collision. The "local controller" manages active runways and the immediate airspace surrounding the airport. The "controller in charge" is a supervisor responsible for the safety of operations, and on the night of the crash, they were also assigned to give pilots departure information.
The NTSB says the staffing was standard operating procedure for LaGuardia at that time of the night, but whether that procedure was adequate will also be investigated.
"We saw that there was a pretty heavy workload for these two controllers where you had an emergency going on; you had several flights that they had to attend to," Homendy told CNN anchor Kaitlan Collins on The Source Wednesday. "We will look at controller staffing entirely in this tower, but then across the national airspace."
Another part of the investigation is to determine which of the controllers were responsible for the aircraft and vehicles on the ground.
"It is not clear who was conducting the duties of the ground controller. We have conflicting information," Homendy said. That person would be tasked with managing all aircraft and vehicle movements on taxiways but typically not active runways.
There is also "conflicting information, including dates and times on the logs," of who else was elsewhere in the air traffic control facility, she said. The NTSB will have to "rectify some of those inconsistencies," Homendy continued.
The controllers involved in the crash continued to work for some time after the crash, and the NTSB will also investigate why they were not relieved more rapidly.
Eighteen minutes after the collision, one controller appeared to blame himself for the crash in a conversation with a pilot who saw it happen.
"That wasn't good to watch," the pilot said in audio recorded by LiveATC.net.
"Yeah, I know. I tried to reach out to them," the noticeably distraught controller said. "We were dealing with an emergency earlier. I messed up."
The pilot responded, "Nah man, you did the best you could."
Investigators will probe far beyond the comment and investigate every aspect of what happened and always note accidents often have complicated causes.
"Our aviation system is incredibly safe because there are multiple, multiple layers of defense built in to prevent an accident," Homendy said. "So, when something goes wrong, that means many, many things went wrong."
The NTSB interviewed the local controller on Tuesday night and continued interviews with others on staff through Wednesday, Homendy said. Investigators will also examine audio recordings the Federal Aviation Administration keeps of every tower radio transmission to determine what exactly was said and by who.
"It looks like it's a communication error," Brauchle said, noting that publicly available recordings of air traffic control audio appear to show "the tower both cleared the aircraft to land, and also cleared the fire truck to cross the active runway."
But he said investigations can sometimes reveal more than is apparent in the first moments.
Why didn't the controllers see the collision coming earlier?
LaGuardia Airport has systems designed to prevent vehicles on the ground from colliding, and investigators will want to know why they were not able to stop this crash.
The airport's surface detection equipment –ASDE-X– uses radar to track ground vehicles but did not warn the controllers ahead of the collision, according to the NTSB.
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"Due to the close proximity of vehicles merging and unmerging near the runway," no alert was issued, Homendy said.
The radar returns on the screen showed two "blobs" on the taxiway, but never showed one go in front of the plane, she said.
Another revelation was that the fire truck involved in the crash was not equipped with a transponder to help air traffic controllers identify it and know its precise location. Though a vehicle without a transponder should show up on radar, no other information would be displayed, and obstructions might prevent radar returns. Why a transponder was not installed will be part of the investigation.
While stressing the need to wait for the investigation's findings, Homendy said Wednesday that she and the team believe all vehicles on tarmacs should have transponders so controllers can see them.
Did the fire truck hear the warning from the control tower to stop?
Another area of the investigation will include looking at the radio transmissions between pilots of Flight 8646, the firefighters, and the control tower.
"Stop. Stop. Stop. Stop, truck 1. Stop," one of the controllers yelled as the fire truck pulled in front of the plane landing on Runway 4.
Nine seconds after the first warning, they collided.
The first radio call the fire truck made to the control tower more than a minute before the collision was "stepped on" by another transmission and was apparently not audible in the control tower, recordings from that night show, but later transmissions appeared to go through.
Investigators will want to know what was transmitted and what was heard, and will review recordings from the control tower, the plane's cockpit voice recorder, and interview other people listening to the frequency that night.
During the investigation into the 2025 midair collision between an Army Black Hawk helicopter and an American Airlines regional jet over the Potomac River, the NTSB found the soldiers in the helicopter didn't hear all the directions given by air traffic control due to a problem with the frequency.
For Sunday's collision at LaGuardia, investigators also will be looking into the status of the airport's runway status lights. These are a type of traffic light system that is embedded in pavement of taxiways and runways.
The lights should, for instance, automatically signal vehicle operators whether it is unsafe to cross a runway,according to the FAA.
"We … know from the replay that the runway status lights were functioning," Homendy said Tuesday. "But we still have to verify that with tech ops from the FAA."
Why was the fire truck cleared to cross the runway?
Perhaps the most vexing question: Why did the controller apparently clear the fire truck to cross Runway 4 when the plane was speeding toward it?
Controllers are working in high stress situations with long hours and busy airfields to manage. Investigators want to know if something was going on with them that may have contributed to the crash.
The two controllers started their shifts about an hour before the 11:37 p.m. collision and at some point took over duties in the tower cab, the NTSB noted.
Shortly before the collision, another plane on the other side of the airport declared an emergency after an aborted landing and odor in the cabin. Controllers dispatched the fire trucks and were working to find a gate for the plane in the minutes before the accident.
"This is a heavy workload environment," Homendy noted, but said no one should jump to conclusions.
"I would caution (against) pointing fingers at controllers and saying distraction was involved," she said. "We still have to determine what happened at shift change, which was around 10:30. We have to determine who else was in the tower and the facility and available at the time. We rarely, if ever, investigate a major accident where it was one failure."
What was going on in the plane?
The cockpit voice recorder and flight data recorder, often referred to as black boxes, are two "critical" pieces to the puzzle in any aviation incident investigation, Peter Goelz, former NTSB managing director and CNN aviation analyst told CNN Monday.
The data recorders are expected to give some insight into what happened during the flight's final moments,capturing everything from what was said in the cockpit, to the sound of switches and automated warnings as well as what the aircraft's instruments were reading.
"They give you the functionality of the plane," Goelz said. "It will tell you exactly when it touched down. Did the pilots attempt to do a go-around? Did the speed brake work effectively? And it will discuss the comments between the pilots on whether they were following procedures, what they saw and how they reacted."
Investigators had to "cut a hole," on top of the aircraft to retrieve the recorders, Homendy said. They were then driven to the NTSB's headquarters in Washington, DC, for analysis.
The cockpit voice recorder contained more than 25 hours of good quality audio across four separate channels, said Doug Brazy, NTSB lead investigator. The flight data recorder contained approximately 80 hours of data and recorded more than 400 parameters.
What will the debris tell us?
While investigators moved quickly to recover data and comb the wreckage before any clue is lost to time or the elements, they have to be careful because some of what is left of the plane and fire truck is complex and hazardous.
"There is a tremendous, tremendous amount of debris from taxiway delta across Runway 4," Homendy said. "It's pretty expansive, and we want to make sure, because as you're walking around, you can get injured. There's also hazardous materials, of course, on the firefighting vehicle itself."
Runway 4 at LaGuardia remains closed until Friday afternoon, according to a FAA notice, while the NTSB conducts its investigation.
The airport, meanwhile, has reopened with flights using a perpendicular runway. As they whiz by, passengers can catch a glimpse of the wreckage and the investigators making sure they understand what went wrong so it never happens again.
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An Air Canada regional jet landing at one of the country's busiest and most prominent airportsslammed into a fire tr...
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