On a Roll in Toronto

Photo by YYZBrennan, CC BY-SA 4.0 , via Wikimedia Commons

It has been a bad year for the airlines. And that’s not the first time that I’ve written that in 2025.

The latest chapter in the saga of air disasters of 2025 occurred Monday in Toronto (which is not the capital of Canada by the way). First, let’s look at the basic facts of the accident.

On Monday, February 17, a Canadair Regional Jet CRJ-900 crashed on landing at Toronto’s Pearson airport. The flight, Endeavor 4819, was operated by Endeavor Air and originated in Minneapolis. The CRJ-900 is in the same family as the CRJ-700 that was involved in the Washington National midair collision last month, and also like that airplane, was operated under a codeshare agreement with a major airline. In the case of the Toronto crash, the flight was a Delta Connection flight, and Endeavor Air is a wholly-owned subsidiary of Delta Air Lines. You can refer back to my comments on the Washington National crash for more details on regional airlines and codeshare agreements.

The first thing that we learn about the crash is that the CRJ was landing when it departed the runway. Post-crash videoshows the airplane resting inverted with its wings torn off. (Cue the scene from Top Gun where Maverick explains, “I was inverted at the time.” I feel comfortable joking since no one died.) There was reportedly a fire as well that was extinguished by crash crews. One of the things that strikes me about the video is the snow on the ground.

I took a look at the Toronto hourly weather report shortly after the crash and shared the screenshot on the platform formerly known as Twitter. The METAR reported wind from 270 degrees at 26 knots gusting to 34 (30 mph gusting to 39). That’s a strong wind, but not as crazy as the 70 mph wind that I initially saw reported by Fox. ATC audio has the tower reporting the wind to the CRJ as 270 at 23 gusting to 33.

Strong winds can be a problem. That’s especially true if the wind is from the side rather than straight on. At some point, airplanes will lose the ability to keep moving straight ahead as they slow for landing if the wind is too great. For this reason, most airplanes have a maximum allowable crosswind component.

Within limits, there are two techniques for maintaining directional control on crosswind landings. One technique is to “crab” the nose into the wind with the rudder and then kick straight as you touch down. The other is to dip the wings into the wind and touch down with the upwind wheel first. The wing-low method is probably the most common for smaller aircraft, but airliners with engines mounted below the wing often favor the crab in order to maintain ground clearance.

I looked up the crosswind component for the CRJ-900 and found a study guide online that is intended for Endeavor pilots. It lists the maximum crosswind component for landing as 32 knots.

Flight Global reports that Endeavor 4819 was landing on runway 23 so we have enough information to do some preliminary calculations. Runways are numbered by their direction so runway 23 means that it is aligned with 230 degrees. It is a simple matter to plug the data into a crosswind calculator. The wind reported by the tower and runway direction yield a crosswind of 15 knots with gusts to 22. Based on that, it seems that the CRJ was within limits.

But wait! There’s more.

The limitation that I just gave you was for dry conditions. If the runway condition is degraded, the allowable crosswind drops. The study guide gives lower numbers for a wet runway (22 knots), a runway with “braking action fair” (20 knots), and a runway with “braking action poor” (15 knots).

The weather report that I posted doesn’t mention the runway condition, but it does mention drifting snow. Snow and ice can degrade stopping and steering performance as you probably know if you’ve ever driven a car on a snowy or icy road. It is very possible that the CRJ crew landed with the aircraft outside the crosswind limitation due to a runway contaminated with snow.

Even without runway contamination, excessive crosswinds can affect airport operations. For example, large airports often use one runway for arrivals and another for departures. When strong winter winds strike an area like New York, crosswinds often make this coordination impossible and cause delays as airports are restricted to a single runway.

We have other information on the crash as well. TMZ has posted a video that shows the moment of the crash. This video, which was apparently taken from a closed-circuit camera, shows an explosion as the CRJ touches down. The angle makes it hard to determine exactly what is happening, but it could be consistent with a failure to maintain the runway due to the crosswind.

Another video has also emerged with a better angle. This video, posted to the platform formerly known as Twitter by the pilot of an airplane apparently waiting to take off, shows the moment of touchdown from the right rear. It is difficult to tell exactly what happens, but the video raises the possibility of a collapse of the right main landing gear. It definitely looks like something catastrophic happened at the moment of touchdown.

It goes without saying that a spontaneous collapse of the landing gear is unusual. Typically, redundant systems monitor that the landing gear is down and locked into place. If these systems don’t detect that all is as it should be, an unsafe gear indication is triggered in the cockpit. In the CRJ, those indications would include both an error message on the crew alerting system (EICAS) and an audible warning of “Too low Gear.”

If the pilots get an unsafe gear indication, there are checklists to follow that would direct the crew to use an alternate extension system. A crew that knew they were experiencing a landing gear problem would probably have notified the tower to have emergency vehicles standing by. It is also likely that they would have diverted to an airport with more favorable weather since none of Toronto’s runways were aligned with the prevailing gusty winds. So far, I haven’t heard any indication that the crew knew there was a problem.

Probably the most common cause of a landing gear collapse is a collision with some sort of obstruction. There is the possibility that some foreign object on the runway might have caused the gear to collapse (if indeed it did), but this is unlikely since the runway was apparently used by other aircraft only a few minutes earlier. That brings us back to the possibility of a runway excursion due to winds that could have caused the landing gear to strike a sign or ditch near the runway.

An honest appraisal of the video does not confirm that the aircraft left the runway, however. Based on the immediate explosion after touchdown, it seems that the plane would have had to initially touch down off the runway for landing to turn catastrophic so quickly. It will be up to investigators to determine exactly where the plane touched down and whether any obstacles contributed to the crash, but if the plane was not lined up with the runway, the crew should have executed a go-around rather than touching down.

The big mystery is what caused the explosion and fire since that probably contributed to the loss of control. One possibility is mechanical problem such as a tire failure. In at least two high profile accidents, exploding tires have caused enough damage to an airplane to destroy it. One of these was the Air France 4590 crash of the Concorde in 2000. A second and lesser known example is the 2008 crash of a Lear 60 carrying Travis Barker, the drummer from Blink 182. The catastrophic failure of a tire can spray the fuselage with fragments that can sever fuel and hydraulic lines, flight control cables, or cause an engine failure.

The ultimate cause of the crash is uncertain at this point. It will likely be the result of a combination of causes. Crosswinds and icy runways may have played a role, but I’m going to go out on a limb and note that even these wouldn’t cause an explosion on landing.

As always with these articles, I’ll stipulate that I’m speculating based on the available data. Air crash investigations are a detailed and thorough process that takes time, but I’m sure we will have an answer to this crash. I’m less certain about the Washington midair.

It is miraculous that all of the 80 passengers and crew escaped with no deaths and no significant injuries. Toronto emergency authorities deserve a lot of credit for their quick response. The same applies to cabin crew that evacuated their charges quickly and safely.

As a final bit of trivia, a great many injuries and deaths could be expected from the fact that the airplane came to rest upside down with the passengers and crew dangling from their seats. I’ve heard of similar cases where people survived crashes and broke their necks when they released their seatbelts to fall on their heads. This is just one more reason the survivors of Flight 4819 should thank God for their lives.