The Gimli Glider: How Precision, Airmanship, and Glider Skills Saved Flight 143 🇨🇦🔥


 Date: July 23, 1983

Aircraft: Boeing 767-233

Flight: Air Canada 143, Montreal → Edmonton

Crew: Captain Robert (Bob) Pearson, First Officer Maurice Quintal

Passengers: 61

Incident: Total fuel exhaustion at 41,000 feet

Outcome: Safe unpowered landing at Gimli, Manitoba


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1. Background: A New Jet, A Metric Mistake


The Boeing 767 was one of Air Canada's newest aircraft — a modern, twin-engine, wide-body jet equipped with electronic flight instrumentation systems (EFIS) and digital fuel management systems.


However, the fuel quantity indicator system (FQIS) had a known fault. Since the Minimum Equipment List (MEL) allowed the aircraft to be dispatched without it (provided fuel was manually confirmed), the crew proceeded — manually calculating fuel using dipsticks and density factors.


Key Failure:


The fuel was calculated in liters, converted to kilograms using the density factor.


But the technician used the incorrect density conversion (lbs instead of kg), loading 22,300 lbs instead of 22,300 kg.


Result: The aircraft departed with only about half the required fuel — enough for 1,200 miles, not the full route.


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2. The Crisis Unfolds: Total Flameout at 41,000 Feet


At cruising altitude over Red Lake, Ontario, the left engine flamed out first, triggering alarms.

Moments later, the right engine also failed, leaving the aircraft completely powerless.

This meant:


No thrust


Loss of electrical systems


Hydraulics failed


Flight displays darkened


No pressurization


Lifeline: The RAT (Ram Air Turbine) — a small propeller that deploys to use the airstream to generate limited hydraulic and electrical power. It allowed partial control of the flight surfaces.


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3. Glide Performance: Turning a Jetliner Into a Glider


Without engines, a Boeing 767 becomes a very heavy glider.


Glide ratio: About 12:1 — for every 1,000 feet of altitude lost, it can glide ~12 nautical miles.


Starting at 41,000 feet, they had around 80 nautical miles of gliding range.


First Officer Quintal quickly calculated they would not reach Winnipeg — the original diversion.

He remembered Gimli, a former RCAF base 70 miles away, where he once trained.


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4. Airmanship Under Pressure: Systems, Strategy, and Skill


The aircraft was descending 3,000+ feet per minute, and systems were rapidly degrading.


What the crew managed:


Manual landing gear extension via gravity drop (but the nose gear didn’t lock).


Maintained lateral control using limited hydraulic power from the RAT.


Communicated with ATC using backup radios.


Calculated glide angle and descent rate on paper — there were no working FMC displays.


First Officer Quintal navigated using dead reckoning — no FMC maps available.


Captain Pearson, a seasoned glider pilot, made the crucial call: to perform a sideslip — a gliding maneuver that increases drag without increasing lift — allowing a fast descent without overshooting the field.


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5. The Hidden Danger: Gimli Was a Racetrack That Day


Unknown to the crew, Runway 32L at Gimli had been converted into a car racing track, complete with:


Concrete barriers


Crowds of spectators


Families camped nearby


But it was still a flat strip of asphalt — and Pearson had no better option.


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6. The Touchdown: Controlled Chaos


The 767 approached too fast and high. With no flaps or spoilers (hydraulics were limited), airspeed control was minimal.


Landing Dynamics:


No reverse thrust


No nose wheel steering


Main gear touched down hard


The nose gear collapsed, sliding on the forward fuselage


Sparks flew, tires blew out, and onlookers scattered


The crew used differential braking to keep the aircraft aligned


Final result: A complete stop on the drag strip, just short of campers.

Not a single fatality. Minor injuries only.


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7. Investigations & Legacy:


Root Causes:


Human error in unit conversion


Inadequate training in metric/imperial transition


Dispatching with a known FQIS fault


Lapses in procedural double-checks


Actions Taken:


Air Canada overhauled metric conversion training


ICAO and national agencies issued guidance on fuel mismanagement prevention


Crew were initially faulted but later honored for heroism and skill


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8. Why It Matters: Real Lessons in Aviation


Crew Resource Management (CRM): Quintal and Pearson operated as a true team under duress.


Airmanship: Pearson’s glider experience directly saved lives.


Training & Systems: Modern avionics mean nothing if fundamentals fail.


Redundancy: The RAT, MEL policies, and judgment call on destination proved essential.


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9. Fast Facts Recap


Fuel Needed: ~20,400 kg


Fuel Onboard: ~10,100 kg


Glide Distance from 41,000 ft: ~80 nautical miles


Landing Gear: Nose gear failed to lock


Landing Site: Active drag racing strip


Casualties: 0 fatalities, 10 minor injuries


Nickname: “Gimli Glider”


Aircraft Later Flew: Until 2008


From quiet skies to runway sparks — the Gimli Glider incident is still studied in aviation schools worldwide. A testament to cool heads, steady hands, and the timeless value of pilot instinct.

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