'Rare' oxygen bottle blast holed Qantas jet

Australian air safety officials on Monday ruled that a "very rare" oxygen bottle explosion was behind a dramatic mid-air blast which forced the emergency landing of a Qantas flight from Hong Kong in 2008.

The Australian Transport Safety Bureau (ATSB) said the "forceful rupture" of one of the aircraft's emergency oxygen cylinders had punched a large hole in the Boeing 747's fuselage, causing rapid depressurisation of the cabin.

Passengers had to use oxygen masks which dropped from the ceiling while the captain immediately brought the aircraft down to 10,000 feet and made an emergency landing at Manila International Airport.

None of the 369 passengers and crew was injured.

"The investigation found no record of any other related instances of aviation oxygen cylinder rupture - civil or military," the ATSB said in its final report into the July 2008 incident.

"Given the widespread and long-term use of this type of cylinder in aerospace applications, it was clear that this occurrence was a very rare event."

The explosion, about an hour into the flight to Melbourne, was so forceful it blew a two-metre wide hole in the plane's body which had debris, wiring and cargo protruding from it at the time of landing.

Investigators were unable to retrieve the bottle, presumed to have been sucked out of the plane over the South China Sea, but the ATSB said a "comprehensive program of testing" was carried out on cylinders of the same type and from the same batch.

"(Testing) did not identify any aspect of the cylinder design or manufacture that could represent a threat to the operational integrity of the cylinders," the ATSB said.

"It is the ATSB's view that passengers, crew and operators... can be confident that the ongoing risk of cylinder failure and consequent aircraft damage remains very low."

The findings come as Qantas grapples with the grounding of its A380 superjumbo fleet following an engine explosion over Indonesia earlier this month.

The national carrier has been plagued with mechanical problems since the November 4 blast, with two Boeing aircraft experiencing engine trouble and a third grounded by a bird strike at Johannesburg last week.

Rolls-Royce has said it may have to replace up to 40 engines on A380s flown by Qantas, Germany's Lufthansa and Singapore Airlines after pinpointing a "specific component" as responsible for an oil fire behind the blast.

Follow Emirates 24|7 on Google News.