Lauda Air Flight 004 was an international passenger flight that crashed due to a thrust reverser deployment of the number 1 engine in flight.
On 26 May 1991, about 23:10 local time, Flight 004 (originating from Hong Kong's Kai Tak Airport), a Boeing 767-3Z9ER, registration OE-LAV, ship name Wolfgang Amadeus Mozart, took off from Old Bangkok International Airport (Don Mueang International Airport) for its flight to Vienna International Airport with 213 passengers and 10 crew, under the command of Captain Thomas J. Welch and First Officer Josef Thurner.
At 23:22, Welch and Thurner received a visual warning indicating that a possible system failure would cause the thrust reverser on the number 1 engine to deploy in flight. Having consulted the aircraft's Quick Reference Handbook, they determined that it was "just an advisory thing" and took no action.
At 23:31, the thrust reverser on the number 1 engine deployed while the plane was over the jungle near Ban Nong Rong (Uthai Thani Province), Thailand. Thurner's last recorded words were, "Reverser's deployed!"
The 767 stalled in mid-air and disintegrated at 4,000 feet (1,200 meters). None of the 223 passengers and crew aboard the airliner survived. It was the first fatal crash of a Boeing 767. The accident remains the deadliest aviation disaster on Thai soil to date. Rescuers found the body of Welch still in the pilot's seat. After the accident scavengers collected electronics and jewellery. About one quarter of the airline's carrying capacity vanished as a result of the crash.
Upon hearing of the crash, Niki Lauda, retired Formula 1 race driver and owner of the airline, travelled to Thailand. He examined the wreckage and concluded that the largest fragment was about five metres by two metres, "about half the size of the largest piece in the Lockerbie crash."
As evidence started to point towards the thrust reversers as the cause of the accident, he made simulator flights at Gatwick Airport which a...