Air Canada

Date: 2015-10-07; view: 519.

XVII. Read and comment on the texts.

On the 23d of July in 1983 a Boeing 767 of Air Canada airline performed the flight from Montreal to Edmonton via Ottawa. In the history of aviation this aircraft is nicknamed as Gimli Glider.

At 26,000 feet fuel pressure alarm went off and one of the engines cut off, in some seconds another engine failed. The instrument panels in the cockpit went blank. Thus the aircraft lost all its power. As on this type of the aircraft the engines supply hydraulic system, it also went dead. The pilots activated ram air turbine, a generator driven by a small propeller, which in its turn is driven by the forward motion of the aircraft. Boeing 767 turned into glider. But judging by co-pilot's and ATC's calculations it wouldn't get to the nearest Winnipeg.

So, the captain made up his mind to perform landing at military base Gimli, a closed air force base where he used to serve as a Canadian Air Force pilot. But he was unaware that that base converted into Motorcar Park. Without hydraulic system pilots lowered the aircraft's main landing gear via a gravity drop, but, due to the airflow, the nose wheel failed to lock into position. The decreasing forward motion of the aircraft also reduced the effectiveness of the Ram Air Turbine, making the aircraft increasingly difficult to control because of the reduced power being generated. The captain also decided to execute a sideslip to increase drag and lose altitude. This maneuver is commonly used with gliders and light aircraft to descend more quickly without gaining forward speed.

The aircraft landed, bursting two tires. Not locked main gear collapsed and the nose of the plane scratched along the RW. None of 61 passengers and crew was seriously hurt.

According to investigation pilots and technical staff were blamed.

Fuel on this type of the aircraft is controlled by quantity information system processor (fqis). It turned out (on the ground) that it was inoperative. On entering the cockpit, the captain spotted blank fuel gauges and a tagged circuit breaker. He consulted the aircraft's Minimum Equipment List (MEL), which told him that the aircraft could not be flown in this condition. That time there had been 55 changes to the MEL, and some pages were still blank pending development of procedures. Consequently it was preferable to be authorized by maintenance personnel and not by MEL.

Technical crew checked the fuel manually by a float stick and flight crew calculated the necessary for the flight amount of fuel manually. They never did this procedure before. Thus for confidence they checked it three times. But crucial mistake was that they didn't take into account that B767 used metric, not feet system.

So, human negligence nearly turned into fatal results.