Engine problem hits another Qantas jet

A Qantas Boeing 747-400 aircraft made an emergency landing in Singapore today after it was forced to return to the city-state due to problems with one of its engines, a Changi airport official and Singapore state TV said.

The four-engine aircraft, with 412 passengers, had left Singapore for Sydney earlier in the evening before it "sought priority clearance to return to Singapore", Channel NewsAsia reported.

"All I can say is QF6 has returned to Singapore. But I cannot state the nature of the problem," the official said.

A Qantas spokeswoman told ABC News "shortly after takeoff the captain experienced an issue with one of its engines".

The spokeswoman said Qantas was waiting to speak to the flight crew for more information.

Qantas' ticketing office in Singapore declined comment, while an unidentified Qantas official told Channel NewsAsia the decision to return to Singapore was "a precautionary matter".

The incident comes a day after a Qantas Airways Airbus A380 was forced to make an emergency landing in Singapore following an explosion in an engine.

The engine failure on Thursday, which scattered debris over an Indonesian island, marked the biggest incident to date for the world's largest passenger plane, in service only since 2007.

It forced Qantas to ground its fleet and other airlines to recheck their own A380s.