It’s been 38 years since the legendary event of the Gimli Glider. On July 23, 1983, Air Canada Flight 143 took off from Montreal, Québec, and headed towards Edmonton, Alberta by way of Ottawa. The plane was a 5-month-old Boeing 767 with 61 passengers and eight crew members aboard. Shortly after 8 p.m., while the aircraft was cruising at 41,000 feet over Red Lake, Ontario, the cockpit crew received a warning of low fuel pressure in the left fuel pump. The pilots first assumed the fuel pump had failed and switched off the alarm, as the Flight Management Computer said there should be plenty of fuel. However, within minutes, the right fuel pump alarm also sounded. The crew then decided to divert the aircraft to Winnipeg, 120 miles away. As they commenced the descent, the left engine failed in a matter of minutes. No sooner had plans for a one-engine landing been made than a loud bang could be heard, and the cockpit alarm began blaring "all engines out!" The plane had lost all power. As if flying with no engines wasn't bad enough, the Boeing 767 was one of the first jets with an electronic flight instrument system powered by its engines. That meant that when the engines stopped working, all the instruments went dark. Thankfully, the ram air turbine was enough to power emergency flight instruments sufficient to land the aircraft. It also provided some hydraulic support for the crew to be able to maneuver the plane, which was not possible by muscular strength alone. However, this didn't include a vertical speed indicator that could have provided an idea of how far the plane could glide. Gimli, an old Air Force Base, was 20 miles closer to the aircraft’s location than Winnipeg. By a stroke of luck, 48-year-old Captain Bob Pearson was an established glider pilot. Even though the decommissioned base had no emergency services, it was deemed to be the safer option. However, neither of the pilots was aware that the base had been turned into a drag racing track – with a major race scheduled for that very day. The nose gear gave out immediately as the plane touched down, but everyone on board survived, though 10 people did suffer minor injuries during the evacuation. Investigators later found out that there were only 64 liters of fuel left in the tanks. The NTSB investigation showed that a fuel error happened because 22,300 pounds of fuel was filled instead of 22,300 kilograms (49,172 pounds). A simple metric system error was the ultimate culprit.
