United Airlines Flight 811

United Airlines Flight 811 was a scheduled flight from Los Angeles, United States to Sydney, Australia, with stops at Honolulu, Hawaii and Auckland, New Zealand. On February 24, 1989, the Boeing 747-122 (registered N4713U) operating the route suffered a failure in a cargo door. This caused an explosive decompression. This resulted in nine passengers dying.

United Airlines Flight 811

N4713U after the cargo door tore off in flight, causing an explosive decompression and ejecting nine people from the plane
Accident
Date	February 24, 1989 (1989-02-24)
Summary	Cargo door failure due to design flaw leading to explosive decompression[1]
Site	Pacific Ocean near Honolulu, Hawaii 20.690°N 158.675°W / 20.690; -158.675
Aircraft
Aircraft type	Boeing 747-122
Operator	United Airlines
IATA flight No.	UA811
ICAO flight No.	UAL811
Call sign	UNITED 811
Registration	N4713U (re-registered N4724U after repairs)
Flight origin	Los Angeles International Airport, Los Angeles, California, U.S.
1st stopover	Honolulu International Airport Honolulu, Hawaii, U.S.
2nd stopover	Auckland Airport Auckland, New Zealand
Destination	Sydney Airport Sydney, Australia
Occupants	355
Passengers	337
Crew	18
Fatalities	9
Injuries	38
Survivors	346

Aircraft

The same aircraft in service with Air Dabia in 1999 at Miami Airport, 10 years after the incident

The incident aircraft, N4713U, was a Boeing 747 which flew for United Airlines. ^[2] The aircraft was given to United Airlines in November 1970.^[3]

Flight

Before the incident, the aircraft flew from Los Angeles, United States to Honolulu, United States.^[2]

It took off from Honolulu at 01:52 local time, with 337 passengers on board.^[1]: 1–2

Seventeen minutes after departure, as the aircraft was flying through 22,000 to 23,000 feet (6,700 to 7,000 m), the flight crew heard a loud thump.^[1]: 2 About a second and a half after the thump, a cargo door opened and opened the fuselage. The resulting pressures caused 10 seats to fly off the aircraft.^{[1]: 8 [4]} All eight passengers in those seats were killed, and another in a seat close to the incident area.^{[1]: 109 [4]}

The pilots first thought a bomb had exploded inside the aircraft. The incident happened two months after Pan Am Flight 103 was blown up over Scotland. They began to fly down in an emergency descent. The aircraft also turned towards Honolulu.^[1]: 2

Debris from the aircraft during the explosive decompression damaged engines number 3 and 4.^[1]: 4–8 Engine number 3 was vibrating fast, so the pilots turned the engine off. Engine number 4 failed and was producing flames, so they turned that engine off.^[1]: 2

As the aircraft was beginning to land, the pilots moved the flaps and landing gear out. However, the flaps could only be moved out a certain distance because of damaged caused by debris.^[1]: 3 The aircraft landed and stopped on the runway.^[4] All passengers and crew left the aircraft in less than 45 seconds.^{[1]: 108–109}

No victims of the incident were found.^[1]: 4 Pieces of clothing and body parts were found in the number 3 engine.At least one victim went into the engine.^[5]