Investigation Summary
While cruising at 29,000 feet, the number 4 oxygen cylinder in a bank of seven located in the forward cargo hold failed catastrophically. The resulting release of high-pressure oxygen caused a localized explosion that created a T-shaped hole in the fuselage approximately 2 meters wide and 1.5 meters high. The force was sufficient to drive the cylinder body through the cabin floor, where it struck the handle of the R2 door, rotating it partially, and hit the overhead panels before falling out through the fuselage breach. The flight crew initiated an emergency descent to 10,000 feet, a process that took approximately five and a half minutes. During the decompression, most oxygen masks deployed, though some passengers reported malfunctions or deteriorated elastic straps. The aircraft landed in Manila with 369 souls on board and several systems unavailable, including the anti-skid braking system for the right-side landing gear and all three instrument landing systems, due to damage to electrical wiring near the blast site.
Final Conclusions
The ATSB concluded that the accident was caused by the sudden failure and forceful discharge of a pressurized oxygen cylinder. Although the cylinder itself was not recovered, metallurgical testing of other cylinders from the same manufacturing batch and computer modeling were conducted. The investigation found no evidence of external explosives, oxygen-promoted fire, or systemic defects in the manufacturing batch. The exact reason for the specific cylinder's failure remained undetermined, though it was hypothesized to have involved a pre-existing flaw or damage that could not be confirmed without the physical evidence of the failed shell.
Photographic Evidence (1)
Video Analysis
Explosive Dilemma | Qantas Flight 30 — A detailed look at the 2008 mid-air explosion on a Qantas Boeing 747 caused by a rupturing oxygen tank over the South China Sea.
If playback is blocked, the owner has disabled embedding — use the link above.
Airframe & Maintenance
Crew Experience
Captain
John Bartels, 53 years old, 25 years with Qantas.
First Officer
Bernd Werninghaus
Second Officer
Paul Tabac
Systems & Failure Modes
Emergency Passenger Oxygen System
A bank of high-pressure cylinders designed to provide oxygen to passengers via drop-down masks; the failure of one cylinder caused the decompression.
Instrument Landing System (ILS)
All three ILS units were rendered unavailable for the landing due to damage to electrical wiring caused by the explosion.
Anti-skid Braking System
The anti-skid braking system for the landing gear on the right side of the lower fuselage was disabled by the blast.
Aileron Control Cables
The First Officer's aileron control cables were severed by the cylinder as it was propelled upward.
Flight Management Computer (FMC)
The Left FMC was rendered unavailable due to electrical wiring damage near the blast site.
Interesting Facts
- 01The fuselage rupture measured approximately 2.0 metres high and 1.5 metres wide.
- 02The oxygen cylinder valve was found inside the cabin, having punched a 20cm hole through the floor.
- 03426 out of 476 oxygen masks deployed correctly during the emergency.
- 04The cockpit voice recorder (CVR) data of the initial explosion was overwritten because the flight continued for two hours after the event.
- 05The aircraft was 475 km north-west of Manila at the time of the decompression.
- 06On 18 November 2008, after repairs were completed, the aircraft was damaged again when another Qantas Boeing 747 collided with it at Avalon Airport.
Safety Actions & Advisories
Fleet-wide Inspection
Qantas completed a program of detailed visual inspections of oxygen system installations across its entire Boeing 747 fleet within days of the accident.
Safety Advisory Notices
The ATSB issued notices recommending that operators ensure oxygen cylinder maintenance and handling procedures meet best practice standards.