What Was the Gimli Glider? Air Canada Flight 143 Explained, Verified November 2026

Last verified: November 7, 2026, at 04:03 UTC (UTC+00:00).

The Gimli Glider was an Air Canada Boeing 767 that ran out of fuel in flight on July 23, 1983. Its pilots glided the powerless aircraft to an emergency landing at a former military airfield in Gimli, Manitoba. All 69 people aboard survived.

The flight became a Canadian aviation landmark because of both the crew’s response and the chain of preventable failures behind the emergency. An official inquiry found that faulty fuel gauges, an incorrect fuel calculation and weaknesses in communication and procedures combined to leave Flight 143 with too little fuel.

Destaques

• Flight 143 was traveling from Montreal to Edmonton, with a scheduled stop in Ottawa.
• Captain Robert Pearson and First Officer Maurice Quintal diverted toward Gimli after both engines failed.
• The aircraft carried 61 passengers and eight crew members; there were no deaths or significant physical injuries.
• The investigation found that a pounds-to-kilograms calculation error was one part of a broader safety breakdown.

What happened to Air Canada Flight 143?

The Boeing 767, registered C-GAUN, departed Montreal for Edmonton via Ottawa with its fuel gauges inoperative. The crew and ground personnel used manual measurements to estimate how much fuel was aboard, but their calculation gave them a misleading picture of the supply.

After the Ottawa stop, the aircraft continued west. The first warnings appeared shortly after 8:00 p.m. Central Daylight Time in the region of the flight, on July 23, 1983 (UTC−05:00; shortly after 01:00 UTC on July 24). The crew initially diverted toward Winnipeg, but both engines stopped as the fuel ran out. The aircraft was then at about 35,000 feet, according to the board of inquiry’s account.

With Winnipeg out of reach, the pilots headed for Gimli. Quintal was familiar with the former Royal Canadian Air Force base, but part of its airfield had since become a motorsports venue. The crew had to bring a large passenger jet down without engine thrust onto a runway that was being used for other activities.

The main landing gear extended, but the nose gear did not lock. It collapsed on touchdown, damaging the aircraft while also helping slow it. The passengers and crew evacuated. The final inquiry report recorded no loss of life and no significant physical injuries.

Why did the Gimli Glider run out of fuel?

The immediate problem was fuel exhaustion, but the explanation reaches back to the aircraft’s fuel quantity indication system. Its fuel gauges were not working when the plane left Montreal and Ottawa. That meant the quantity had to be checked manually using drip-stick readings, which were converted into a volume and then a weight.

The crucial error came in converting liters of fuel into kilograms. Personnel used a factor of about 1.77, which produced a weight in pounds, but treated the result as kilograms. A kilogram is about 2.2 pounds, so the mistake made the fuel supply appear much larger than it was. A check in Ottawa repeated the same kind of error rather than revealing it.

The inquiry did not reduce the accident to a single person confusing two units. It described a joint effort by flight crew and maintenance personnel, unclear responsibility for the calculations, inadequate training and communication, and problems with manuals and procedures. It also concluded that the aircraft should have been grounded with its fuel gauges inoperative. The fuel processor malfunction set the other failures in motion, but the safeguards meant to catch the problem did not hold.

How could a passenger jet glide without engines?

Airliners generate lift as air flows over their wings. If their engines stop, they do not immediately fall straight down: they can trade altitude for forward motion while the pilots control their speed and direction. A glide still has a limit, however. The crew must find a suitable landing place before the aircraft runs out of altitude.

Flight 143’s crew also had to manage the loss of systems normally supported by the engines. Emergency equipment and standby instruments helped them retain essential control and information, while air traffic control supplied distance information as they assessed whether a landing site was reachable. Pearson used a sideslip on the approach to help lose height before landing, according to accounts of the flight.

The Royal Canadian Air Force’s history of the incident describes the glide and landing at the former base that gave the aircraft its enduring nickname.

What happened after the Gimli Glider landed?

The aircraft was repaired and returned to airline service. The incident also prompted detailed scrutiny of how a modern airliner could depart with defective gauges and a fuel shortage despite multiple opportunities to detect the problem.

Its lasting lesson is broader than a warning to convert units carefully. A calculation can look convincing when everyone uses the same mistaken assumption, and a repeated check may reproduce an error instead of catching it. Clear responsibilities, usable procedures, functioning equipment and independent verification all matter when a normal system fails.

Flight 143 remains a historical case, not evidence of a new aviation incident. Its value for readers today is in understanding how equipment failures and human decisions can interact—and why a successful emergency response does not erase the failures that made it necessary.

Frequently asked questions

Did everyone survive the Gimli Glider?

Yes. All 61 passengers and eight crew members survived. The inquiry reported no significant physical injuries.

Where did the Gimli Glider land?

It landed at the former military airfield in Gimli, Manitoba, where part of the site was being used for motorsports.

Was the Gimli Glider caused only by a metric conversion error?

No. The wrong conversion factor was central, but investigators also identified a malfunctioning fuel indication system and shortcomings in training, communication and procedures.