Air Transat Flight 236

Synopsis

On 24th August 2001, Air Transat 236, an Airbus A330 aircraft was flying from Ontario, Canada to Lisbon, Portugal, when the crew noticed a fuel imbalance; subsequently, the aircraft’s right engine and light engine both flamed out. Due fuel exhaustion, the pilot initiated a diversion to Lajes Airport, Terceira Island in the Azores. The pilot successfully carried out an engines-out, visual approach landing with no loss of lives.

The reason for both engines flaming out was due to maintenance installing an incorrect part in the hydraulics system; with the wrong part, there was no adequate clearance between the hydraulic line and fuel line leading to degradation to the fuel line during vibration in the hydraulic line, hence causing a leak in the number two engine.

Due to the leak, the pilots noticed a fuel imbalance between the fuel tanks but did not recognize the problem as a possible fuel leak situation and instead carried out the fuel imbalance procedure from memory and incorrectly (causing them to miss warnings that indicated it could be a fuel leak problem) which resulted in them trying to correct the problem by opening a cross-feed valve between the tanks. This exacerbated the issue and caused fuel from the operational tank to be drained out through the leak in the number two engine, leading to fuel exhaustion in both engines and flame out.