What is Lauda Air Flight 004?
{{Infobox aircraft occurrence | image = Lauda Boeing 767-3Z9ER OE-LAV (Cropped).jpg | image_upright = 1.25 | alt = | caption = OE-LAV, the [[Lauda Air]] Boeing 767-3Z9ER involved in the accident | occurrence_type = Accident | date = {{start date|1991|05|26|df=y}} | summary = In-flight break-up caused by uncommanded [[Thrust reversal|thrust reverser]] deployment | site = [[Phu Toei National Park]], [[Suphan Buri Province|Suphan Buri]], [[Thailand]] | coordinates = {{coord|14|56|48|N|99|27|10|E|region:TH-72_type:landmark|display=inline,title}} | aircraft_type = [[Boeing 767|Boeing 767-3Z9ER]] | aircraft_name = ''[[Wolfgang Amadeus Mozart|Mozart]]'' | operator = [[Lauda Air]] | tail_number = OE-LAV | origin = [[Kai Tak Airport]], [[Hong Kong]] | stopover = [[Don Mueang International Airport|Don Mueang Int'l Airport]], [[Bangkok]], [[Thailand]] | stopover0 = | last_stopover = | destination = [[Vienna International Airport]], [[Vienna]], [[Austria]] | occupants = 223 | passengers = 213 | crew = 10 | fatalities = 223 | injuries = | missing = | survivors = 0 }} '''[[Lauda Air]] Flight 004''' was a scheduled international passenger flight from [[Kai Tak Airport|Kai Tak]], [[Hong Kong|Hong Kong, China]] to [[Vienna International Airport|Wien-Schwechat International Airport]], [[Vienna]], [[Austria]] via [[Don Mueang International Airport]], [[Bangkok]], [[Thailand]]. On 26 May 1991, during it's Bangkok to Vienna leg, the [[Boeing 767]]-3Z9ER operating the route suffered from a rare uncommanded [[thrust reverser]] deployment while flying over the Burma-Thai border and crashed into wooded terrain about ~94 nautical miles northwest of Bangkok, killing all 213 passengers and 10 crew members on board. It is the first and deadliest loss involving the Boeing 767, and as of 2022, Thailand's worst aviation accident. The positions of the left engine thrust reverser actuators along with data from the electronic engine control (EEC) and the cockpit voice recorder (CVR) indicate that the left engine thrust reverse system deploye