Qantas oxygen cylinder blast mystery

There is no evidence of systemic safety problems with aircraft oxygen bottles, according to an interim report on the explosion of an oxygen bottle on a Melbourne-bound Qantas flight in July last year.

The explosion ripped a huge hole in the side of a Qantas Boeing 747 which was flying from Hong Kong to Melbourne causing a sudden loss of air pressure in the cabin.

The second interim report by the Australian Transport Safety Bureau (ATSB) released today indicates there is no evidence of systemic safety problems with oxygen bottles of the type involved in the accident.

It said various tests have not been able to replicate the cylinder failure that occurred on board the jet.

It said all pressure tests of the cylinders met or exceeded the relevant safety specifications, with recorded rupture pressures being over twice the maximum working pressure of the cylinders.

Other work is being carried out to determine the minimum size of mechanical flaws that could result in cylinder failure in service.

The flight, which originated in London and was carrying 365 passengers and crew, plunged 6000 metres before stabilising, then made an emergency landing in the Philippines capital Manila.

The ATSB expects to conclude its investigation in early 2010.