‘Something unusual happened’: Here’s what aviation experts said about the Delta crash at Toronto Pearson airport

Former pilot Keith Mackey says there was a substantial cross wind upon landing.

In a whirlwind of events, a Delta Air Lines plane crashed into a runway at Pearson International Airport in Toronto on Monday afternoon.

Images captured from the scene showed the commercial aircraft, which was carrying 80 people, upside down while first responders attended the scene. Around 18 people were injured.

Flight 4819 was arriving from Minneapolis-Saint Paul, Minn.

What happened?

According to aviation expert John Gradek, a fuel leak and severe wind gusts may have contributed to the dramatic crash of the plane.

A crash survivor, John Nelson, told CNN that passengers could “smell jet fuel.”

“When you have that type of situation, the fuel running down the windows of the airplane on landing, the wing got ripped off the airplane, and that’s where the fuel tanks are,” Gradek, a lecturer at McGill University’s School of Aviation Management, told CTV’s Your Morning Tuesday.

He explained the ruptured fuel tanks likely led to fires on both side of the aircraft.

Passengers’ accounts describe the plane hitting the ground hard before flipping over, with one individual reporting seeing an “explosion” on one side of the aircraft, according to CNN.

Landing challenges

Gradek emphasized that landing a large commercial plane involves carefully managing a number of critical factors including wind, runway conditions and braking systems.

“You’re taking an airplane from 400 kilometres an hour and you got to stop it on that runway,” he said.

Air traffic control audio captured the moments after the plane crash. An air controller is heard speaking with an air ambulance dispatched to the scene and warns the pilot of people on the runway surrounding the overturned plane.

Gradek said the landing window is important and the crew must be vigilant for control issues that may occur at the time.

He noted it is unusual for a large commercial aircraft to flip like a small plane, indicating that “something unusual happened” in the last few seconds, during the landing, that caused the plane to veer off course and ultimately flip.

Keith Mackey, an aviation safety consultant, also had a few ideas of what could have gone wrong.

He said video appears to show the airplane approaching the runway amid cloud cover “with fairly limited visibility.”

“The airplane appears to be descending very rapidly and doesn’t flare as you’d expect it to as it approaches the runway, so I think that was what happened with the hard landing and I think it was just beyond the structural capability of the airplane,” Mackey said in an interview with CTV News Channel from Ocala, Fla., on Tuesday. The flare is the transition phase before the plane touches down, allowing the plane to land gently.

He said the cause of the crash probably won’t be officially released for a year or two.

Evacuation and survival

Nelson said he recalled being upside down and falling into the ceiling. “Then everybody was just like, ‘Get out, get out, get out,’ we could smell jet fuel,” he added.

“Some people were saying they were hanging like bats,” Gradek said. Given these accounts, he added that passengers would have had to unbuckle their seatbelts and then jump down in a “chaotic” scene.

In footage captured and circulated on social media, passengers could be seen evacuating the overturned plane as flight crew and airport staff appear to assist them.

Unravelling the precise chain of events that led to the dramatic crash will be up to investigators.

“Hopefully we’ll find out rather quickly as to what exactly happened,” Gradek said, pointing out that the data from the black boxes and communication between air traffic control and the flight crew will be crucial in piecing together the final moments of the flight.

Mackey said it was a miracle there were no casualties.

“This is really a tribute to the maker of that airplane,” Mackey said. “Bombardier certainly designed a well-built airplane to be able to take that abuse and also the flight attendants around this flight deserve a lot of accolades for getting everybody off there safely in minimum amount of time with very little injuries. So a lot went right. Unfortunately, we have to find out what did go wrong. That will be the next step.”

With files from CTVNewsToronto.ca’s Alex Arsenych, CP24’s Joshua Freeman and CTVNews.ca’s Christl Dabu.