Gimli Glider Incident Investigation By Lee Xuan Hong

Overview  In this investigation, we will find out what the incident is about and why the incident occurred.

Summary of Incident(1)  Gimli glider is the nickname of the Air Canada aircraft, which was involved in an incident due to maintenance errors.  Air Canada Flight 143, a Boeing jet (Gimli glider), ran out of fuel at feet high when it was halfway through its journey to Edmonton via Ottawa from Montreal.

Summary of Incident(2)  However, the flight crew successfully glided the aircraft to an emergency landing safely.  The aircraft was nicknamed Gimli glider because it glided to a landing at Gimli Industrial Park Airport.

Date of Incident July July

Timeline Day before Incident Day of Incident Day before Incident Day of Incident Aircraft flew from Toronto to Edmonton Aircraft flew from A pre-flight inspection was Edmonton to Montreal, made by a maintenance then from Montreal to engineer for the next flight Edmonton. (incident the next day occurred) the next day occurred)

Day before Incident  The aircraft flew from Toronto to Edmonton where it underwent routine checks.  The engineer there noticed that the Fuel Quantity Indicator System (FQIS) was not working unless he disabled one of the 2 measuring sensors. By doing so, the fuel gauges in the cockpit were restored to working order but with only 1 FQIS measuring sensor operative.

Day of Incident(1)  The aircraft flew to Montreal from Edmonton. Before the plane departed, the engineer informed the pilot of the problem with the FQIS and that the fuel in the tanks would have to be checked with the floatstick (an instrument used to measure fuel for aircrafts).  The pilot however, misunderstood and thought that the plane had been flown with the fault the previous day.

Day of Incident(2)  On arriving at Montreal, there was a crew change for the return flight back to Edmonton. The outgoing pilot informed Captain Pearson and First Officer Quintal of the problem with the FQIS and passed on his mistaken belief that the plane was flown the previous day with this problem. In a further misunderstanding, Captain Pearson believed that the FQIS had been totally unserviceable.  An engineer who was investigating the problem with the FQIS re-enabled the measuring sensor which was originally disabled in order to test the system. As a result, the fuel gauges in the cockpit went blank. It was then when the engineer was called away, forgetting to disable the measuring sensor.

Day of Incident(3)  As a result, Captain Pearson wasn’t surprised to see blank fuel gauges when he entered the cockpit. Thus, they measured the fuel via floatstick. It was then when they made a critical error…

Conversion Error  As fuel was added to the aircraft, a conversion error was made. Correct Calculation Wrong Calculation (A litre of fuel was 0.803kg) Weight of 1 litre of fuel in pounds 7682 litres × = 6169 kg Weight of fuel 7682 litres x 1.77 = kg kg − 6169 kg = kg already in plane kg – kg = 8703kg kg ÷ = litres 8703 kg ÷ 1.77 kg = 4916 litres of fuel of fuel to be transferred to be transferred Fuel requirement of kg for the plane litres of fuel already in the tanks Weight Required Instead, of litres, 4916 litres of fuel was transferred. The same error was made when the plane stopped for refueling at Ottawa. Thus, the plane left for Edmonton with no chance of reaching there.

Running out of Fuel and Landing  Therefore, the plane ran out of fuel at feet altitude.  Fortunately, Captain Pearson was an experienced glider pilot and he executed a forward slip to increase drag and lose altitude so that the aircraft will descend more quickly. He “stood” on the brakes as soon as the wheels touched the runway.  The nose of the aircraft scraped against the runway as the nose wheel was forced back into its well.  None of the passengers were seriously hurt.

Conclusion  After investigation, the reasons of the air crash were found to be: -Wrong conversion factor used -Carelessness of the engineers -Misunderstanding between the previous pilot and Captain Pearson  In other words, a chain of minor human errors led to this incident.

The End Sources: Wikipedia, Google, glider-july html glider-july html