Aviation expert explains what could have caused Qantas engine failure

An aviation expert has outlined the likely cause of the Qantas engine failure that sparked a grassfire at Sydney Airport this afternoon.

Speaking to 9News, Professor Ron Bartsch said while the investigation into the incident is still in its early stages, the most likely culprit would have been one of the blades in the Boeing 737's engine.

"An engine failure at any stage of an air transport operation-type operation is a very, very rare occurrence these days," Bartsch said.

READ MORE: Qantas confirms engine failure after grassfire sparked at Sydney Airport

"Most likely there's been some failure of a blade, perhaps a turbine blade or a compressor blade, that's caused this.

"It's very early stages (of the investigation) but it's obvious it's a catastrophic event or failure...

"It's very hard to specifically state what's happened, but obviously the pilots have done a very good job to get back on the ground safely."

The flight ended up making an emergency landing back at Sydney Airport, but Barstch said bringing the plane back to ground wouldn't have been the hardest part of the operation for the crew.

READ MORE: Passengers heard 'bang' after engine failure on Brisbane-bound Qantas flight

"Probably more difficult from a pilot's point of view is if it was an engine failure, the most critical phase of flight is an engine failure at or near V1 on take-off," he said.

"V1 is a decision speed. If an aircraft hasn't reached that speed it's got sufficient runway and stopway to pull up.

"It's obvious that if it was an engine failure, it's happened after V1, so controlling any aircraft on take-off at a high maximum take-off weight and in hot conditions is a very, very difficult task.

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"But obviously the pilots are trained to handle emergency situations such as this. But again, a very, very rare occurrence."

While passengers heard a loud bang just before take-off, Qantas has said there was no explosion, although confirmed the engine failure did cause the ensuing grassfire.

There were no injuries on board or as a result of the fire, but Sydney Airport has had extensive delays due to the fire.

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