The Gimli Glider
By Sam Longo AME, A&P
Its not very often that you hear of a modern jetliner gliding, engines silent, for some 250 kms, with the flight terminating in a successful dead stick landing. However, 25 years ago, on July 23, 1983, Captain Bob Pearson and First Officer Maurice Quintal managed to do just that.
Air Canada’s Boeing 767-200, C-GAUN, fin number 604 was forever afterward known as the Gimli Glider. During my maintenance career with Air Canada I had on many occasions worked on that very aircraft. In my humble opinion I always felt that the incident was a bit of a set-up right from day one.
The Canadian Government was on its all-metric kick and forced the company (at additional cost) to purchase its new 767s using all metric fuel measuring systems (kilograms and litres) when the standard of the industry was still pounds and gallons. The second part of the set-up for the unsuspecting flight crew was the ongoing problem with the FQIS (Fuel Quantity Information System). The subsequent investigation showed the system was only working on one of its two channels due to a bad soldered joint in the fuel tank capacitance gauges.
Due to poor communication on crew switch over the Captain was lead to believe the system was completely unserviceable, when in fact it was still working on one channel. Unfortunately a maintenance worker inadvertently reset a pulled circuit breaker that subsequently rendered all channels U/S. With blank fuel gauges and a constantly changing MEL (Minimum Equipment List) due to the newness of the aircraft, the Captain made a judgment call. He accepted maintenance clearance and calculated his fuel load based on numbers supplied only from the fuel quantity drip sticks. Drip sticks are manual devices that maintenance personnel can unlock and pull down on the underside of each wing tank. Simply put, when fuel streams out of a small-calibrated orifice a number is recorded from the stick’s protruding length. When all these numbers are plotted on a graph it can give a very accurate account of how much fuel is on board.
The drip stick numbers were dutifully taken and delivered to the flight deck. Unfortunately due to improper information (and next to no training on the procedure) the flight crew used the wrong conversion factor. Despite checking the math three times they only had 10,000 kg of fuel onboard, however their incorrect calculations assured them they had 22,300 kg. And so the stage was set for a potential disaster.
Flight 143 originated in Montreal, made a scheduled stop in Ottawa and proceeded to Edmonton. A short while later at 41,000 feet, somewhere over Red Lake, Ontario the cockpit’s warning system sounded, signaling a fuel delivery problem on the aircraft’s port side. Soon after the port engine flamed out, the crew prepared for a single engine landing with a diversion to Winnipeg. Seconds later the starboard engine flamed out and 604 began its silent descent. For the record, flight simulator training does not include powerless gliding. Despite a ram air turbine to give minimal hydraulics for flight controls, both pilots were now charting unfamiliar territory.
Some rough calculations using crude backup instruments and additional information from Winnipeg’s ATC radar established a glide ratio of approximately 12 to 1. Captain Pearson’s extensive gliding experience may have helped him guesstimate his chosen glide velocity of approximately 220 knots (407 km per hour). However, despite their best efforts, it soon became clear, they were never going to reach Winnipeg. Fortunately, First Officer Quintal remembered his air force training base at Gimli Manitoba, and a quick calculation confirmed that the aircraft could make it.
Meanwhile, on the ground at Gimli Industrial Park Airport (the former airbase) it was “Family Day” for the Winnipeg Sports Car Club. Much to their surprise, Captain Bob Pearson skillfully dropped the gear and side slipped the big Boeing onto an unused section of the runway. Had the nose gear not collapsed, it would have been a picture perfect landing. As it was, the accomplishment was simply incredible.
Subsequently Air Canada disciplined the flight crew while shortly thereafter in 1985 the same crew was awarded the first ever Fédération Aéronantique Internationale Diploma for Outstanding Airmanship. Captain Pearson continued his flying career with the airline, as did the Gimli Glider. Pearson retired in 1993 but aircraft 604 continued flying for almost 25 years. On January 24, 2008 the old girl was fueled up in Montreal for the last time, her destination, the bone yard in the Mojave Desert. Captain Pearson and First Officer Quintal were on board to oversee that final flight. I am happy to report she made it, with fuel to spare.
One last little known fact about the legend of the Gimli Glider, turned out to be an interesting coincidence. The Air Canada maintenance crew assigned to drive from Winnipeg to Gimli to repair the aircraft, ran out of gas en route and were stranded until a back up crew arrived. Two days later aircraft 604 was ferry flown back to the maintenance base in Winnipeg, subsequently becoming, perhaps the most famous Boeing 767 of all time.