Last November, an engine on a Qantas A380 taking off from Singapore exploded. Shards of metal burst out of the massive cowling, punching holes in the wing and fuselage, severing wires and shredding fuel and hydraulic lines. By a stroke of luck, two additional A380 pilots happened to be on board, and they helped the captain and his two officers struggle for an hour and a half to cope with the aftermath of the uncontained engine failure. The team managed to get the airliner and its 469 passengers and crew safely back on the ground, averting what could have been the third-deadliest aviation accident in history.
Airliner engines concentrate inrushing air with spinning compressors, dump fuel into the airstream and ignite the mixture to produce thrust.
A tube that carries oil to lubricate bearings.
The pipe in the Airbus’s engine was poorly made; one of its walls was too thin. Subjected to engine vibration, it eventually cracked, leaking oil.
Bearing-structure buffer space
The gap between rotating discs and the assembly supporting them.
The flammable oil sprayed between the bearing and the turbine discs, one of the hottest parts of the engine.
Intermediate-Pressure (IP) turbine disc
The power to turn the compressor blades comes from this spinning disc.
The IP disc is designed to handle extreme temperatures, but when the leaking oil caught fire within the buffer space, its metal heated past the failure point.
Long, thin edges that rotate in the stream of hot gases exiting the engine.
Spinning at several thousand revolutions per minute, the blades’ tips moved as fast as bullets. When the IP disc failed, the blades flew apart in a spray of shrapnel, nearly destroying the airliner.
Modern turbofan engines operate so close to the limits of material science that a single small flaw – in this case, in an oil pipe – can lead to catastrophic failure. European regulators required other airlines to check their Rolls-Royce Trent 900 engines for the same problem, and the company says its engineers have devised a fi x. Most aviation experts expect no similar failures.
By Jeff Wise