Qantas Flight 72 (QF72) was a scheduled flight from Singapore Changi Airport to Perth Airport. On 7 October 2008, the flight made an emergency landing at Learmonth Airport near the town of Exmouth, Western Australia following an inflight accident that included a pair of sudden, uncommanded pitch-down manoeuvres that caused severe injuries—including fractures, lacerations and spinal injuries—to several of the passengers and crew. At Learmonth, the plane was met by the Royal Flying Doctor Service of Australia and CareFlight. Fourteen people were airlifted to Perth for hospitalisation, with 39 others also attending hospital. In all, one crew member and 11 passengers suffered serious injuries, while eight crew and 99 passengers suffered minor injuries. The Australian Transport Safety Bureau (ATSB) investigation found a fault with one of the aircraft’s three air data inertial reference units (ADIRUs) and a previously unknown software design limitation of the Airbus A330‘s fly-by-wire flight control primary computer (FCPC).
On 7 October 2008, Qantas Flight 72 was scheduled to fly from Singapore Changi Airport (SIN) to Perth Airport (PER). The aircraft, VH-QPA, was delivered new to Qantas on 26 November 2003, initially as an A330-301. In November 2004, it had a change in the type of engines fitted, and was re-designated as an Airbus A330-303.
The crew was led by Captain Kevin Sullivan (53), a former US Navy (1977-1986) pilot. The first officer was Peter Lipsett, and the second officer was Ross Hales. In addition to the three flight-deck crew members, there were nine cabin crew members and 303 passengers, for a total of 315 people on board. Captain Sullivan had 13,592 flight hours, including 2,453 hours on the Airbus A330. First Officer Lipsett had 11,650 flight hours, with 1,870 of them on the Airbus A330. Second Officer Hales had 2,070 flight hours, with 480 of them on the Airbus A330.
On 7 October 2008 at 09:32 SST, Qantas Flight 72, with 315 people on board, departed Singapore on a scheduled flight to Perth, Western Australia. By 10:01, the aircraft had reached its cruising altitude of around 37,000 feet (11,000 m) and was maintaining a cruising speed of Mach 0.82.
The incident started at 12:40:26 WST, when one of the aircraft’s three air data inertial reference units (ADIRUs) started providing incorrect data to the flight computer. In response to the anomalous data, the autopilot disengaged automatically. A few seconds later, the pilots received electronic messages on the aircraft’s ECAM, warning them of an irregularity with the autopilot and inertial reference systems, and contradictory audible stall and overspeed warnings. During this time, the captain began to control the aircraft manually. The autopilot was then re-engaged and the aircraft started to return to the prior selected flight level. The autopilot was disengaged by the crew after about 15 seconds and would remain disengaged for the remainder of the flight.
At 12:42:27, the aircraft made a sudden, uncommanded pitch down manoeuvre, experiencing −0.8 g,[note 1] reaching 8.4 degrees pitch down and rapidly descending 650 feet (200 m). Twenty seconds later, the pilots were able to return the aircraft to the assigned cruise flight level, FL370. At 12:45:08, the aircraft made a second uncommanded manoeuvre of a similar nature, this time causing an acceleration of +0.2 g,[note 2] a 3.5 degree down angle, and a loss of altitude of 400 feet (120 m); the flight crew was able to re-establish the aircraft’s assigned level flight 16 seconds later. Unrestrained (and even some restrained) passengers and crew were flung around the cabin or crushed by overhead luggage, as well as crashing with and through overhead compartment doors. The pilots stabilised the plane and declared a state of alert, which was later updated to mayday when the extent of injuries was relayed to the flight crew.