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“Holy shit.”

Inside the cockpit of the cruising airliner, Captain Bob Pearson was understandably alarmed at the out-of-the-ordinary beeps that were chiming from his flight computer. On the control panel, an amber low fuel pressure warning lamp lit up to punctuate the audio alarm.

First Officer Maurice Quintal, copilot of Air Canada Flight 143, checked the indicator light to determine the cause of the computer’s complaints. “Something’s wrong with the fuel pump,” he reported.

The mustachioed Captain Pearson pulled out the trusty Boeing handbook, his fingers dashing through the pages to find the specifics of the warning. To his relief, the troubleshooting chart indicated that the situation was not as perilous as it might seem: the fuel pump in the left wing tank was signaling a problem, a minor issue considering that gravity would continue to feed the engines even if the pump failed.

“You know,” he commented to Copilot Quintal, “I would not take this air…” He trailed off as the computer blurted out another four beeps, and the indicator panel lit up like a Christmas tree decorated with bad news. “Oh fuck,” Pearson lamented, “we’ve got to go to Winnipeg.”

The date was 23 July 1983, and although the fuel pressure warnings were not the flight’s first mechanical frustrations, they were certainly the most distressing so far. When pilots Pearson and Quintal had arrived for their shift earlier that day, they had been notified that the plane’s fuel gauges were non-functional due to a fault in the Fuel Quantity Indicator System (FQIS). Even worse, the component required to repair it could not be delivered until later that evening.

Rather than canceling the flight, Captain Pearson instructed the engineers to check the fuel level manually. The four-month-old 767 was a state-of-the-art machine with state-of-the-art glitches, and FQIS issues were becoming a common complaint. Several independent dripstick checks later, the fuel hosers were satisfied that sufficient fuel was loaded, and they advised Air Canada Flight 143 to take off. The airliner departed from Montreal at 5:48pm eastern time with their sixty-one passengers. At 6:58pm they made a brief scheduled stopover in Ottawa, where engineers once again checked the fuel dripsticks⁠— just to be safe.

It was just after 8:00pm central time that the cockpit computer began its string of inexplicable beeps and warning lights. As the jumbo jet crossed the Canadian countryside at 41,000 feet, Copilot Quintal thumbed through the 767 handbook to ascertain the nature of the airplane’s problem. “They don’t say anything if you’ve got more than one though, main tank, eh?” he said to Captain Pearson, as well as the flight engineer who had joined them. “Like there’s two pumps, they don’t say anything about only one, eh?” According to the computer’s calculations there should have been plenty of fuel remaining, but multiple fuel pumps were indicating pressure problems. The flummoxed flight crew decided to divert to the nearby Winnipeg airport as a precaution, and alerted Air Traffic Control (ATC) of their intent.

The cockpit of a typical Boeing 767

“Air Canada 143 cleared present position direct Winnipeg,” the tower responded. “We’re landing runway 31. You’re cleared to maintain six thousand descent your discretion.” Pearson and Quintal updated their flight computer with the new heading and destination. “Air Canada 143 did you want any assistance?” the traffic controller inquired, where “assistance” is an aeronautic euphemism for a reception from the fire brigade.

“For the moment we won’t require any assistance,” Pearson responded.

The flight engineer struggled to assess the situation. “You’ve got nothing in the center tanks, eh?” he inquired of the captain.

“No, we ran the pumps,” the captain replied, referring to an earlier attempt to transfer fuel from another tank. “Uh, let’s put them back on again.” Within moments, several more warning lights snapped on in quick succession. “Holy shit.”

“God damn,” Quintal remarked, “they’re all going out, eh? How about uh…”

“All the lights are on,” Pearson observed soberly, as the array of low fuel pressure indicators glowed with incandescent urgency. The captain summoned the in-charge flight attendant to the cockpit and apprised him of the situation, but his summary was outdated mere moments later. The flight computer bellowed out a flamboyant BONG! which none of the men present could recall having heard before.

“Okay,” the captain observed upon examining the instruments, “We’ve lost the left engine.”

“Okay, what…will we do?” Quintal replied. “Want the checklist now?”

“Checklist, yeah.”

The pilots began preparations for a delicate-but-very-doable single-engine landing, and Copilot Quintal contacted Winnipeg tower to request the previously offered “assistance”. It was becoming increasingly clear that the plane’s problems lay not in its machinery, but in its fuel. The men, however, were unsure of exactly what was amiss.

Following two minutes of uneventful descent, the ever-present vibrations in the deck were disrupted by an almost imperceptible shudder, and the white-noise hum of the remaining jet engine faded away with a long and melancholy mechanical sigh. The gauges and monitors of the control panel⁠— which had been so animated with anxiety mere moments before⁠— fell dark. Absent the usual murmur of the twin turbofans, an unsettling silence hung heavy in the air.

“How come I have no instruments?” Captain Pearson wondered aloud, though the answer lingered mockingly in the cockpit’s uncharacteristic quiet. The airliner’s generators and hydraulic systems required at least a single functioning engine in order to operate, without which there was no electricity for the computer, and no power to manipulate the ailerons, rudder, and elevator. In effect, the highly advanced flying machine had roughly the maneuverability of a flying brick, with barely enough instrumentation to monitor its slow dive towards the Earth. After a few ponderous moments, however, the automatic emergency systems twitched into action. Onboard batteries revived a few of the most critical instruments, and a door popped open on the plane’s underbelly to expose a ram-air turbine (RAT) designed to provide limited emergency hydraulic support.

“143,” the radio crackled, “We have lost your transponder return right now.”

Captain Bob Pearson

Captain Pearson was beginning to grasp the true gravity of the situation. “Center, one-four-three, this is a mayday and we require a vector onto the closest available runway. We are out of 22,000 feet on… both engines have failed due to looks like fuel starvation and we are on emergency instruments and can only give you limited headings. Information⁠— we are heading two five zero now, please give us a vector to the nearest runway.”

“143 we copy all that okay. We have lost your transponder return and attempting to pick up your target now… we have it now, just stand by on the two fifty heading.”

“Ah, roger.”

After repeated unsuccessful attempts to restart the stalled engines, Pearson and Quintal once again consulted the 767 emergency manual, this time for advice on an unpowered landing. Much to their dismay, no such section existed, presumably because a simultaneous engine failure had been too ridiculous for Boeing engineers to contemplate. The pilots sat anxiously in their darkened cockpit and monitored the plane’s slow and silent descent using a handful of analog instruments based on pre-WW2 technology: a magnetic compass, an artificial horizon, an airspeed indicator, and an altimeter.

The traffic controller in the tower at Winnipeg advised the flight officers of their options. “143 we show you at sixty-five miles from Winnipeg and approximately forty-five miles from Gimli.”

“Okay,” Pearson responded, “is there emergency equipment at Gimli?

“Negative emergency equipment at all. Just one runway available I believe and no control and no information on it.”

“We’d prefer Winnipeg then.”

In a stroke of profound luck, Captain Pearson was an accomplished glider pilot, a skill which afforded him with some sense of the vehicle’s glide capabilities. He applied his expertise to estimate the plane’s best glide ratio speed, but having neither a vertical speed indicator nor a view of the landscape through the clouds, he was unaware that Winnipeg was well beyond the reach of their gravity-gripped flight equipment.

Back in the passenger compartment, the in-charge flight attendant radiated counterfeit calm as he informed the plane’s sixty-one passengers of the situation, and instructed them in the subtle art of not freaking out during an in-flight emergency. In the meantime, crew members directed able-bodied men to move into the rows alongside the exit doors, then solemnly buckled into their own seats. Many of the crew members were keenly aware that jumbo jets such as theirs were not designed for dead-stick flight⁠— let alone dead-stick landings. In all probability, their inevitable confrontation with the Earth would not be an improvement on their current situation.

As the impromptu glider emerged from the ceiling of clouds and obtained a view of the landscape, the pilots quickly realized that the plane was shedding altitude far too quickly to have any chance of reaching Winnipeg. Copilot Quintal confirmed this conclusion using radar data from Air Traffic Control.

“How far are we from Gimli?” Pearson inquired of the Winnipeg tower.

“You are approximately twelve miles from Gimli right now.”

Air Traffic Control had no specific data on the remote airstrip, but in another stroke of luck, First Officer Quintal had been stationed there during his time in the Royal Canadian Air Force. Lacking any feasible alternative, the copilot recommended they drop in on his old friends from the service. He was not aware, however, that the facility had since been converted into a public airport; nor did any of the men know that one of its two runways had been decommissioned and carved up for use as a racetrack.

As Flight 143 fell below the Air Traffic Control radar range, the tower grimly requested a count of the souls on board. As Pearson began his long final approach, he scraped up a bit of optimism as he updated Winnipeg tower on their status. “We have the field in sight,” he reported, “and we feel we’re in good shape.”

On the ground at Gimli, it was Family Day at the local racetrack. Sports Racers buzzed along the decommissioned runway as spectators cheered from the sidelines. A collection of campers at the end of the airstrip soaked up the summer Saturday evening as their dinners sizzled on assorted barbecues. Without the jet engines to announce the airliner’s approach, the people were oblivious of the 132-ton Boeing behemoth which was bearing down on them.

In the cockpit, Copilot Quintal activated the manual landing gear controls, and the two main gears lowered and locked. The nose gear, however, dangled limply from its housing. For Captain Pearson, the flight controls were becoming increasingly difficult to operate. The effectiveness of the emergency RAT was governed by the speed of the wind slipping around the fuselage, so as the plane gradually slowed, the hydraulic assistance was diminishing. Nevertheless, Pearson needed to sharply reduce the speed and altitude of his approach, otherwise the 767 would overshoot the tarmac; and without engines there would be no opportunity for a second try. Ordinarily an airline pilot would apply some combination of reverse thrust, flaps and aerobrakes, but none of these systems were functioning on Pearson’s crippled craft.

Lacking a more orthodox option, Captain Pearson cranked the control wheel to the right and gave the left rudder pedal a firm stomp. The criss-crossed controls tilted the deck to the right as one wing dipped toward the ground, providing the passengers with a lovely view of the golf course on one side, and nothing but blue sky on the other. The fuselage also rotated its heading to the left, becoming diagonal relative to its direction of travel. Such forward-slip maneuvers were sometimes used on small planes and gliders, but the curve-ballish air acrobatics were unheard of with a jumbo jet. The airplane indeed decelerated, but the reduced airspeed robbed the controls of even more precious hydraulic pressure, requiring Pearson to apply monumental force to try to straighten the slip.

Orientation of the aircraft during forward slip maneuver

At the opposite end of the runway, the Family Day campers and spectators had finally spotted the silent and oddly-angled incoming aircraft, and they were scrambling from its path with appropriate levels of panic. First Officer Quintal caught sight of the fleeing families, but it was far too late to revise their landing plans, so he opted not to distract the captain with the unsettling discovery.

Forty feet above the ground⁠— mere seconds before contact⁠— Captain Pearson managed to wrestle Flight 143 back to a straight and level approach. At 8:38pm central time, the rear landing gears grabbed the tarmac at Gimli airport, and Bob Pearson stood on the brake pedals as the airplane skidded towards the scattering bystanders. A few of the loudly protesting tires finally succumbed to the abuse and blew out with adequate force to shimmy the fuselage. As some of the weight shifted forward, the unsecured front landing gear buckled, dumping the nose section onto the pavement and spraying a three-hundred foot shower of sparks.

After sledding across the asphalt for 2,900 feet, Air Canada Flight 143 ground to a halt just a few hundred yards from the shocked onlookers. There was a moment of stupefied contemplation within the passenger cabin, followed by an eruption of cheering and applause. Meanwhile several astute racetrack workers dashed to the nose of Flight 143 and doused a small friction-induced fire using hand-held extinguishers. Within a few minutes the inflatable rubber escape chutes plopped from the sides of the plane, and the sixty-nine frazzled occupants disembarked.

A crew of engineers from Winnipeg airport clambered into a van and headed for Gimli to assess the damage. During transit, however, their vehicle unexpectedly ran out of fuel, nearly ripping a hole in the delicate space-irony continuum. When airline mechanics finally arrived at the landing site, they found all three of the 767’s fuel tanks completely dry, with no evidence of a fuel leak. A review of the day’s events traced the problem back to the manual dripstick checks in Montreal and Ottawa. In order to maintain awareness of the overall weight of the aircraft, flight crews kept track of fuel quantity based on kilograms rather than the fuel company’s liter-based measurements. Pearson and Quintal had determined the fuel weight by multiplying the the number of dripsticked liters by 1.77, as indicated by the documentation. However, unbeknownst to the pilots and the fuel crew, this multiplier provided the weight in imperial pounds; the new, all-metric 767 was based on kilograms, and required a multiplier of 0.8. As a consequence of this documentation disconnect, Flight 143 had left Montreal with roughly half the necessary fuel.

Because the rear escape slides were excessively steep due to the buckled front gear, a few bumps and bruises were sustained on egress; but no one was seriously injured in the Gimli incident. Had it not been for Pearson’s capable captaining and glider experience, as well as Quintal’s cucumber-cool support, the outcome of the metric mixup might have been considerably less pleasant. In addition, had it not been for the drag created by the collapsed front gear, the powerless plane would have plunged into the crowd of spectators, sowing destruction and death in its wake. All told, the soon-to-be-dubbed “Gimli Glider” was a nearly perfect demonstration of dead-stick flying, accompanied by an extra-large portion of good fortune.

The Gimli after landing (photo by Wayne Glowacki, Winnipeg Free Press)

With just two days of mechanical jiggering, Captain Pearson’s wounded 767 was patched up sufficiently to fly it out for repairs elsewhere. The Gimli Glider officially rejoined the Air Canada fleet after a bit of body work, a new front gear, a new wiring harness, a repaired Fuel Quantity Indicator System, and a full load of jet fuel. The internal investigation into the incident laid the blame partially upon Captain Bob Pearson and First Officer Maurice Quintal, who should have observed the Minimum Equipment List (MEL) and grounded the aircraft since it lacked functioning fuel gauges. Some of the responsibility was also assigned to the maintenance workers, and to “corporate deficiencies.” As a consequence Pearson was briefly demoted, and Quintal was suspended for two weeks. Nonetheless both pilots continued to work for Air Canada, and in 1985 they received the well-deserved Fédération Aéronautique Internationale Diploma for Outstanding Airmanship for their handling of the unusual landing.

As for the Gimli Glider herself, the twenty-four year old 767 remains an active part of the Air Canada fleet to this very day. Some grizzled old pilots swear that sometimes, when the wind is just right on a quiet night, you can just about make out the double-engine-failure BONG! as the old girl is flying by; and if you’re very lucky, you might catch the faint odor of damp pilots in the air.

Update: The Gimli Glider–Air Canada Flight 143–was retired from service on 24 January 2008 in a ceremony involving Captain Robert Pearson, First Officer Maurice Quintal, and three of the six flight attendants who had been aboard Flight 143 during its unscheduled glide and rough landing.