Qantas Airways suspended flights of its Airbus A380 fleet on Thursday after engine failure triggered an emergency landing in Singapore, one of the most serious incidents for the world's largest passenger plane in three years of commercial flight.

The Airbus A380, which had originated in London and was carrying 459 people, suffered failure of one of its four engines shortly after it had left the island state en route for Sydney. Australian officials said no one on board was injured.

Qantas, which operates six A380s, said it was grounding the aircraft pending a full investigation.

"We will suspend all A380 takeoffs until we are fully confident we have sufficient information about (flight) QF32," Qantas chief executive Alan Joyce told reporters in Sydney.

"...The A380 is a fantastic aircraft. This issue of an engine failure is one we have not seen before. We are obviously taking this very seriously, because it was a significant engine failure."

Initial media reports said the plane had crashed after an explosion over the Indonesian island of Batam, near Singapore.

The reports sent the Australian carrier's shares lower but they later recovered.

There have been no fatal incidents involving A380s since they were launched in 2005 amid great fanfare as the greenest, quietest -- as well as the biggest -- jetliner.

Singapore Airlines said it was not grounding its A380 fleet but that it was closely assessing the situation. Emirates also said it was not considering suspending flights as its engines are from a different supplier.

Qantas A380s use Rolls-Royce Trent 900 engines. The plane involved in the incident was built in 2008.

The A380 has been bedevilled with production delays. More than 200 orders have been placed for the aircraft, and 37 are in operation worldwide, according to Airbus. Qantas said the incident did not impact its standing orders for more A380s.

Earlier this year, one of the planes operated by Qantas burst two tyres when landing in Sydney, and in September 2009 an A380 was forced to turn around in mid-flight and return to Paris.

"This is probably the most serious incident involving the A380 since it began flying in commercial service," said aviation expert Tom Ballantyne, chief correspondent of Orient Aviation magazine. "There have been minor engine incidents before but nothing like this."

Holding pattern

Qantas has never had a fatal accident. A mid-air explosion blew a minivan-size hole in the side of a Qantas 747-400 in 2008 which Australian air safety investigators blamed on an oxygen bottle.

Singapore's Channel NewsAsia said the plane circled Singapore to burn fuel before making an emergency landing.

Passenger Christopher Lee told ABC radio the passengers heard a bang, and reported rattling in the cabin.

"Some of the passengers then alerted cabin staff that there was an explosion, there was smoke or something to that effect. We circled in a holding pattern above Singapore for about an hour." He said passengers were kept informed at all times.

"It appears from the images of the plane that one of the engines has experienced a failure and it looks to be a fairly massive internal failure at that," said Peter Marosszeky at the University of New South Wales' aviation department.

"This failure has caused some of the engine ducting known as bypass ducting to depart from the engine. This type of incident has been seen previously but it was a long time ago and with much older planes than the A380."

A Reuters reporter said the plane was surrounded on the ground by emergency vehicles but there was no sign of any smoke or fire. One of the four nacelles -- structures that house the engines -- was missing and there appeared to be charring around that area of the plane.

Indonesian TV showed pictures of a small amount of debris on the ground near Batam airport which it said belonged to the Qantas plane.

Rusdi, a witness in Batam, told Indonesia's Metro TV: "After an explosion, the plane was still moving but smoke was trailing from one of its wings."

Thursday's incident came just days before Qantas was due to celebrate its 90th anniversary with a special open day in Brisbane. – Reuters