A Delta Air Lines regional jet has flipped upside down upon landing at Canada's Toronto Pearson Airport amid windy weather following a snowstorm, injuring 18 of the 80 people on board, officials say.

Three people on flight DL4819 from Minneapolis-St Paul International Airport suffered critical injuries, among them a child, a Canadian air ambulance official said, with 15 others also immediately taken to hospitals.

Some of the injured have since been released, Delta said later.

The US carrier said a CRJ900 aircraft operated by its Endeavor Air subsidiary was involved in a single-aircraft accident with 76 passengers and four crew members on board.

The 16-year-old CRJ900, made by Canada's Bombardier and powered by GE Aerospace engines, can seat up to 90 people.

At least one of the two wings was no longer attached to the plane, video showed after the accident.

Canadian authorities said they would investigate the cause of the crash, which was not yet known.

Emergency responders work near the aircraft at Toronto Pearson International Airport. – Reuters

Passenger John Nelson posted a video of the aftermath on Facebook, showing a fire engine spraying water on the plane that was lying belly-up on the snow-covered tarmac.

"We're in Toronto. We just landed. Our plane crashed. It's upside down. The fire department on site. Upside down. Everybody, most people appear to be OK," Nelson narrated in the video.

"We're all getting off. Some smoke going on." 

He later told CNN there was no indication of anything unusual before landing.

"We hit the ground, and we were sideways, and then we were upside down," Nelson said.

"I was able to just unbuckle and sort of fall and push myself to the ground. And then some people were kind of hanging and needed some help being helped down, and others were able to get down on their own," he said.

Peter Carlson, a passenger traveling to Toronto for a paramedics conference, said the landing was “very forceful.”

“All the sudden everything just kind of went sideways and then next thing I know it’s kind of a blink and I’m upside down still strapped in,” he told CBC News.

Carlson said when he took off his seat belt he crashed onto the ceiling, which had become the floor. He smelled gas, saw aviation fuel cascading down the cabin windows and knew he needed to get out but said his fatherly intuition and paramedic skills kicked in. He looked for those he could help.

Carlson and another man assisted a mother and her young son out of the plane and then Carlson dropped onto the tarmac. Snow was blowing and it “felt like I was stepping onto tundra.”

“I didn’t care how cold it was, didn’t care how far I had to walk, how long I had to stand – all of us just wanted to be out of the aircraft,” he said.

Toronto Pearson Airport said earlier it was dealing with high winds and frigid temperatures as airlines attempted to catch up with missed flights after a weekend snowstorm dumped over 22cm (8.6 inches) of snow at the airport.

A firefighter at the Delta Air Lines plane crash site at Toronto Pearson International Airport. – Reuters

The Delta plane touched down in Toronto at 2.13pm (1913 GMT) after an 86-minute flight and came to rest near the intersection of runway 23 and runway 15, FlightRadar24 data showed.

The reported weather conditions at time of the crash indicated a "gusting crosswind and blowing snow," the flight tracking website said.

Toronto Pearson Fire Chief Todd Aitken said the runway was dry and there were no crosswind conditions, but several pilots who had seen videos of the incident pushed back against this comment.

US aviation safety expert and pilot John Cox said there was an average crosswind of 19 knots (22mph) from the right as it was landing, but he noted this was an average, and gusts would go up and down.

"It's gusty so they are constantly going to have to be making adjustments in the air speed, adjustments in the vertical profile and adjustments in the lateral profile," he said of the pilots.

"It's normal for what professional pilots do."

Investigators would try to figure out why the right wing separated from the plane, Cox said.

Michael J McCormick, associate professor of air traffic management at Embry-Riddle Aeronautical University, said the upside-down position made the Toronto crash fairly unique.

"But the fact that 80 people survived an event like this is a testament to the engineering and the technology, the regulatory background that would go into creating a system where somebody can actually survive something that not too long ago would have been fatal," he said.

Three previous cases of planes flipping over on landing involved McDonnell Douglas's MD-11 model.

In 2009, a FedEx freighter turned over on landing at Tokyo's Narita airport killing both pilots. In 1999, a China Airlines flight inverted at Hong Kong, killing three of 315 occupants.

In 1997, another FedEx freighter flipped over at Newark with no fatalities.

The plane rests upside down after the crash. – Reuters

Flights have resumed at Toronto Pearson, but airport president Deborah Flint said there would be some operational impact and delays over the next few days while two runways remained closed for the investigation.

She attributed the absence of fatalities in part to the work of first responders at the airport.

"We are very grateful that there is no loss of life and relatively minor injuries," she said.

The audio recording from the tower at Toronto Pearson International Airport shows the flight was cleared to land at about 2:10pm local time.

The tower warns the pilots of a possible air flow bump in the glide path as the plane comes into land because of a preceding aircraft in front of it.

In the recording Tower controllers were heard speaking with the crew of a medical helicopter that had just left Pearson and was returning to help with the crash.

The plane came to a rest at the intersection of Runways 23 and 15L, the controller said. That’s not far from the start of the runway.

“Just so you’re aware, there’s people outside walking around the aircraft there,” a tower controller said.

“Yeah, we’ve got it. The aircraft is upside down and burning,” the medical helicopter pilot responded.

Boards list delayed and cancelled flights at Toronto Pearson International Airport. – Reuters

"It’s very rare to see something like this,” said John Cox, CEO of aviation safety consulting firm Safety Operating Systems in St Petersburg, Florida. “We’ve seen a couple of cases of takeoffs where airplanes have ended up inverted, but it’s pretty rare.”

Cox, who flew for US Air for 25 years and has worked on NTSB investigations, said the CRJ-900 aircraft is a proven aircraft that’s been in service for decades and does a good job of handling inclement weather.

“The weather conditions were windy. The wind was out of the west at 27 to 35 knots, which is about 38 miles an hour (61km/h). So it was windy.

"But the airplanes are designed and certified to handle that. The pilots are trained and experienced to handle that."

Among the questions that need to be answered, Cox said, was why plane was missing a right wing.

“If one wing is missing, it’s going to have a tendency to roll over,” he said. “Those are going to be central questions as to what happened to the wing and the flight data recorder and cockpit voice recorder.

"They will be found, if not today, tomorrow, and the Transportation Safety Board of Canada will read them out and they will have a very good understanding of what actually occurred here.”

First responders at the Delta Air Lines plane crash site at Toronto Pearson International Airport. – Reuters

The Transportation Safety Board of Canada (TSB) said it was deploying a team of investigators, and the US National Transportation Safety Board said a team of investigators would assist Canada's TSB.

Global aviation standards require a preliminary investigation report to be published within 30 days of an accident.

Japan's Mitsubishi Heavy Industries, which closed a deal to buy the CRJ aircraft program from Bombardier in 2020, said it was aware of the incident and would fully cooperate with the investigation.

It is at least the fourth major aviation mishap in North America in the past month. A commercial jetliner and an Army helicopter collided near the nation’s capital on January 29, killing 67 people.

A medical transportation plane crashed in Philadelphia on January 31, killing the six people on board and another person on the ground and 10 were killed in a plane crash in Alaska.

Recent aviation disasters in North America

The crash of a Delta Air Lines plane in Toronto is the fourth major aviation disaster in North America in the last month. Here's a look at the other crashes.

Commuter plane crashes in Alaska, killing all 10 aboard

A small commuter plane on its way to Nome crashed on February 6, killing the pilot and nine passengers.

The Bering Air single-engine turboprop Cessna Caravan was traveling from Unalakleet when it disappeared about an hour after taking off. The Coast Guard said the aircraft went missing about 30 miles (48km) southeast of Nome.

After a wide search, the plane's splintered body and debris were found the next day on the sea ice.

The day of the crash there was light snow and fog, with a temperature of 17F (-8.3C).

The commuter flight was part of a workhorse network of short-hop flights that people in the immense and rugged state rely on to get to medical appointments, attend work meetings, buy essential supplies or even travel to away sports games.

The victims included two men who were on a work trip to service a heat recovery system vital to a community's water treatment plant, a retired teacher who was on a trip mentoring other teachers, and another person who was flying for a doctor's appointment.

Air ambulance crashes onto busy Philadelphia street, killing seven

A medical transport jet with a child patient, her mother and four others aboard crashed into a Philadelphia neighbourhood on January 31, exploding in a fireball that engulfed several homes. The crash killed seven people, including all those aboard, and injured 19 others.

The Learjet 55 took off and then plummeted in a steep descent, crashing less than a minute after takeoff from the Northeast Philadelphia Airport.

The plane hit the ground during a busy Friday evening less than 3 miles (5km) from the airport, leaving a crash scene covering at least four blocks.

A father who was inside his car when the small plane crashed was among those killed.

The plane operated by Jet Rescue Air Ambulance was on its way to Mexico, returning the child, who had spent months in treatment at Shriners Children's Philadelphia hospital.

Jet Rescue is based in Mexico and has operations both there and in the US.

Helicopter and plane collide near Washington, killing 67

A midair collision between an Army helicopter and an American Airlines flight about to land at Washington's Ronald Reagan National Airport on January 29 killed all 67 people aboard the two aircraft. It was the country's deadliest aviation disaster since 2001.

The regional jet out of Wichita, Kansas, was carrying 60 passengers and four crew and preparing to land when the helicopter apparently flew into its path, causing a collision that sent both aircraft into the icy waters of the Potomac River.

The UH-60 Black Hawk, based at Fort Belvoir, Virginia, was on a training exercise and carried three soldiers.

Among those killed were members of the Skating Club of Boston who were returning from a development camp that followed the 2025 US Figure Skating Championships in Wichita.

The victims also included a group of hunters returning from a guided trip in Kansas, four members of a steamfitters' local union in suburban Maryland, nine students and parents from Fairfax County, Virginia, schools and two Chinese nationals.