The captain of a Qantas Airbus A330 carrying 168 passengers to Singapore had to shut down an engine and turn back to Perth after an oil warning light flashed, the airline said Saturday.

The plane flew back to the west Australian city on one engine after the mid-air drama on Friday. Passengers were rescheduled on a replacement flight that took off nearly five hours late.

"Initial inspections by engineers indicate that a fault with the engine starter motor could have led to the engine oil problem," Qantas spokesperson David Cox told the Sydney Morning Herald.

The incident was the latest in a series of problems suffered by Australia's troubled national airline in recent months.

Last week two Qantas jumbos were damaged when they collided on the ground at a maintenance base.

In October, a computer glitch caused a Qantas plane to do a 200-metre mid-air nosedive, injuring more than 70 people, with some suffering broken bones.

In July, a Qantas Boeing 747-400 made an emergency landing in Manila after a mid-air blast caused by an exploding oxygen bottle punched a hole in the fuselage during a flight from Hong Kong to Melbourne.

AFP