Description

On 26 May 1991, a Boeing 767-300 being operated by Austrian carrier Lauda Air on a scheduled passenger service from Hong Kong to Vienna via Bangkok was climbing in night Visual Meteorological Conditions (VMC) when it went out of control and crashed fifteen minutes after departure from Bangkok about 100 nm northwest of the airport. The aircraft was destroyed and all 223 occupants were killed.

Investigation

An Investigation under the provisions of Annex 13 was carried out by the Aircraft Accident Investigation Committee of the Thai Ministry of Transport and Communications. The Investigation found that “flight operations appear(ed) to have been routine until five minutes and forty five seconds after the cockpit voice recorder (Cockpit Voice Recorder (CVR)) recorded the sounds of engine power being advanced for takeoff. At this point a discussion ensued between the crew members regarding an event later identified as a crew alert associated with a thrust reverser isolation valve. The crew discussed this alert for some four and one half minutes. The Quick Reference Handbook (Quick Reference Handbook (QRH)) was consulted to determine appropriate crew actions in response to the alert. No actions were required, and none were identified as being taken. Ten minutes and twenty seconds into the flight the co-pilot advised the pilot-in-command of the need for rudder trim to the left. The pilot-in-command acknowledged the co-pilot's statement. Fifteen minutes and one second into the flight, the co-pilot stated "ah reverser's deployed." Sounds similar to airframe shuddering were then heard on the CVR. Twenty nine seconds later the CVR recording ended with multiple sounds thought to be structural breakup.”