Qantas Blast Caused By Oxygen Tank

Sydney, Australia (AHN) - Investigators which probed the blast that created a hole on a Melbourne-bound Qantas plane confirmed the mid-air explosion was caused by an oxygen tank.

Pieces of the oxygen tank's cylinder valve handle, valve pressure relief assembly and body and green paint smudges were found between the door of the economy and business class of the ill-fated aircraft.

But while they pinpointed the source of the blast, the investigators could not explain why the tank blew up.

Because of the explosion, which occurred July 25, the Boeing 747 which left Hong Kong was forced to make an emergency landing in Manila with all 365 crew and passengers safe despite the 5-foot hole.

The Australian Transport Safety Bureau released the interim report Friday. Julian Walsh, acting executive director of the bureau, told media, "There's nothing at this stage that the ATSB can identify what could have been done to prevent this because we don't really know why the bottle failed - and that's the key question for the investigation."

Previous Qantas investigation of oxygen systems on its Boeing 747-400 fleet showed it had no safety issues.