Flights Gone Wrong

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Boeing 747 Crashes: What Each Accident Found and What Changed

The Boeing 747 flew for more than half a century, and a handful of its accidents changed how every airliner is built, flown and protected. This guide covers the 747 events on this site and other landmark cases, with what each investigation found and the safety rules that followed.

Published 7 min read

The Boeing 747 has been involved in some of the deadliest events in aviation, including the worst accident of all, the 1977 runway collision at Tenerife. But most of its famous losses had causes outside the aircraft’s design: a take-off without clearance, a bomb, a faulty repair. Where the design was at fault, as with TWA Flight 800’s fuel tank, the fixes reached far beyond the 747.

This guide sets out what each 747 investigation found and what changed afterwards, with the accident rates to read them by. To watch the videos, go to Boeing 747 in the library.

The 747 in brief, and how to read its record

Because a 747 carries so many people, one 747 accident can kill more people than many smaller accidents together. That makes its accidents prominent, but it does not on its own say how safe the aircraft was.

The fairer measure is the accident rate per million departures. Boeing publishes these figures in its yearly Statistical Summary. They are a manufacturer’s figures, and they leave out events caused by hostile action, such as sabotage, hijacking, terrorism and military action. So Pan Am 103 is not counted.

747 variantHull lossesHull losses with fatalitiesRate per million departures (fatal hull loss / all hull loss)Edition
747-100, -200, -300 and SP37191.46 / 2.851959–2018
747-4001160.64 / 1.171959–2025

The later 747-400 has a much lower rate than the early models. Boeing’s 2025 edition notes that the 747-100, -200, -300 and SP have not operated commercially in the last five years.

Tenerife, 1977

On 27 March 1977 two 747s, KLM Flight 4805 and Pan Am Flight 1736, collided in fog on the runway at Los Rodeos Airport, Tenerife. Both had been diverted there after a bomb exploded at Las Palmas. The KLM aircraft began its take-off without clearance and struck the Pan Am aircraft as it taxied on the same runway. All 248 people on the KLM jet and 335 on the Pan Am jet were killed, 583 in all, making it the deadliest accident in aviation history. Sixty-one people on the Pan Am aircraft survived.

Spain’s investigators found that the fundamental cause was the KLM captain taking off without clearance, not obeying “stand by for take-off”, and not aborting when Pan Am reported it was still on the runway. The Tenerife airport disaster page has the full timeline. The changes that followed, in radio phrasing and crew resource management, are in What changed after Tenerife.

Olympic Airways Flight 411, 1978

On 9 August 1978 an engine failed as Olympic Airways Flight 411, a fully loaded 747-200 bound for New York, lifted off from Athens on a hot day. Moments later the flight engineer switched off the water injection system, which boosts engine thrust, believing the water had run out. The three remaining engines lost that boost, and the aircraft barely climbed, crossing a hill at Alimos with only feet to spare and flying low over the city.

Over the sea, with go-around thrust finally set, the 747 climbed away. The crew dumped fuel and landed back at Athens about an hour after take-off. All 418 people on board were unhurt.

No state accident report was published. A Boeing performance analysis for the Greek Civil Aviation Authority found no airframe or engine fault behind the poor climb. It found that switching off water injection, with thrust left below go-around power, removed the margin a heavy 747 needed on a hot day.

Pan Am Flight 103, 1988

On 21 December 1988 Pan Am Flight 103, a 747-121 flying from London Heathrow to New York, was destroyed by a bomb over Lockerbie, Scotland. All 259 people on board and 11 residents of Lockerbie were killed. How investigators traced the bomb is covered in Pan Am Flight 103: How a Tiny Fragment Traced the Lockerbie Bomb.

The UK Air Accidents Investigation Branch found that the in-flight disintegration was caused by the detonation of an improvised explosive device in a baggage container on the left side of the forward cargo hold (AAIB report 2/90). The forward fuselage and flight deck separated within two to three seconds. The airport security and criminal sides were investigated separately. The changes in aviation security that followed are in What changed after Pan Am 103.

TWA Flight 800, 1996

On 17 July 1996 TWA Flight 800, a 747-131 bound from New York to Paris, broke apart off Long Island about 12 minutes after take-off. All 230 people on board were killed.

The NTSB found that the fuel and air mixture in the nearly empty centre wing tank exploded. The ignition source could not be determined with certainty. The most likely source was a short circuit outside the tank that let excessive voltage into it through wiring for the fuel quantity indication system (NTSB/AAR-00/03). The investigation led to new rules on fuel tank wiring and to nitrogen inerting systems in airliner fuel tanks. Our guide to in-flight fire accidents covers the fuel tank rules in detail. The video TWA Flight 800: How a Wiring Fault Ignited an Empty Fuel Tank walks through the most likely ignition source.

Other landmark 747 accidents

Japan Air Lines Flight 123 now has its own event page; the others are not yet on this site. They are named here because each one changed something.

  • Japan Air Lines Flight 123, 12 August 1985. A 747SR’s rear pressure bulkhead ruptured about 12 minutes after leaving Tokyo. The rush of air destroyed the fin and severed all four hydraulic systems. The crew kept the aircraft in the air for about 32 minutes with engine thrust alone. According to the FAA, 505 passengers and 15 crew were killed and four people survived. The bulkhead had been repaired after a tail strike years earlier, and the repair was installed improperly, leading to early fatigue failure.
  • Korean Air Lines Flight 007 (1983) and Air India Flight 182 (1985). Both were 747s destroyed by deliberate acts. They will be covered here once their event pages are written from the official reports, including the 2010 report of Canada’s Commission of Inquiry into the Air India bombing, “Air India Flight 182: A Canadian Tragedy”.
  • El Al Flight 1862, 4 October 1992. Shortly after leaving Amsterdam, a 747 freighter lost both right-wing engines and their pylons and crashed into an apartment building in the Bijlmermeer district. The inboard engine had failed first and struck the outboard one. The case led to a closer look at the structural fuse pins that are meant to let an engine break away safely.
  • China Airlines Flight 611, 25 May 2002. A 747-200 broke up near 35,000 feet over the Taiwan Strait with 225 people on board. The FAA’s summary of the Taiwanese investigation says the breakup started near the aft lower fuselage, where a repair after a 1980 tail strike had been made over scratched skin that was never removed.

What the 747 accidents taught

Runway procedures and crew culture. Tenerife led to stricter radio phrasing, so that the word “take-off” is only used in a take-off clearance, and to the spread of crew resource management.

Structural repairs. JAL 123 and China Airlines 611 both broke up because of repairs made years earlier. Both show that a repair has to be as sound as the original structure and has to be inspected for fatigue for the rest of the aircraft’s life. Our guide to maintenance errors covers this pattern.

Cargo doors. In February 1989 the forward cargo door of United Airlines Flight 811, a 747 climbing out of Honolulu, separated in flight, causing an explosive decompression. The aircraft landed safely at Honolulu. The FAA’s lessons-learned material on cargo doors cites it as a later example of the same hazard first seen on the DC-10.

Fuel tank safety. TWA 800 changed how every airliner’s fuel tanks are wired, inspected and, increasingly, filled with inert gas.

Aviation security. Pan Am 103 led to the Aviation Security Improvement Act of 1990 in the United States and to requirements to reconcile checked bags with the passengers who check them.

The Boeing 747 topic page lists every 747 event on this site, and Deadliest plane crashes by decade places these accidents in the wider history.

Table: the 747 accidents in this guide

YearFlightCause categoryFatalitiesInvestigating body
1977KLM 4805 and Pan Am 1736, TenerifeRunway collision; take-off without clearance583Subsecretaría de Aviación Civil (Spain)
1978Olympic Airways 411, AthensEngine failure on take-off; thrust management0No state report; Boeing analysis for the Greek CAA
1985Japan Air Lines 123Structural failure after an improper repair520Japan (summarised by the FAA)
1988Pan Am 103, LockerbieBombing270 (259 on board, 11 on the ground)AAIB (UK)
1996TWA 800, Long IslandCentre fuel tank explosion230NTSB (US)
2002China Airlines 611, Taiwan StraitStructural failure after an improper repair225 on boardAviation Safety Council (Taiwan), summarised by the FAA

Watch in the library

Every video on this subject is on the Boeing 747 page.

Sources

  1. FAA, summarising the Spanish Subsecretaría de Aviación Civil report. Lessons Learned: KLM Flight 4805 and Pan Am Flight 1736, Tenerife (PH-BUF) Source
  2. AAIB (UK). Aircraft Accident Report 2/90, Boeing 747-121, N739PA, Lockerbie, 21 December 1988 Read the report
  3. NTSB. NTSB/AAR-00/03, In-flight Breakup Over the Atlantic Ocean, Trans World Airlines Flight 800, Boeing 747-131, N93119 Source
  4. Boeing for the Greek CAA (no URL). Olympic Airways Flight 411: Boeing performance analysis for the Greek Civil Aviation Authority (1978); no state report published online
  5. FAA. Lessons Learned: Japan Air Lines Flight 123 (JA8119) Source
  6. FAA (summarising the Taiwan Aviation Safety Council report). Lessons Learned: China Airlines Flight 611 (B-18255) Source
  7. FAA (summarising the Dutch investigation). Lessons Learned: El Al Flight 1862 (4X-AXG) Source
  8. Boeing (manufacturer’s data). Statistical Summary of Commercial Jet Airplane Accidents, Worldwide Operations 1959–2025 (April 2026) Source
  9. Boeing (manufacturer’s data). Statistical Summary of Commercial Jet Airplane Accidents, Worldwide Operations 1959–2018 (copy hosted by Transport Canada) Source

More guides

All guides

  • What Changed After Tenerife: CRM and Clearer Radio Calls

    What changed

    The 1977 runway collision at Tenerife killed 583 people and turned on a few words of radio and a cockpit where no one stopped the captain. This guide explains the two big changes that followed, standard radio phrasing and crew resource management, and where they have since saved lives.

  • What Changed After Pan Am 103: How Airport Security Evolved

    What changed

    Pan Am Flight 103 was destroyed by a bomb hidden in a suitcase over Lockerbie, Scotland, on 21 December 1988, killing 270 people. This guide explains what the investigators found about the aircraft’s break-up and how airport and airline security changed in the years that followed.

  • In-Flight Fire Accidents: Swissair 111, TWA 800 and What Changed

    Causes

    A fire on board leaves a crew very little time, and the most dangerous fires start where nobody can see them: above a cockpit ceiling, in a cargo hold or inside a fuel tank. The investigations into Swissair 111, Swissair 551 and TWA 800 changed what airliners are built from, how fuel tanks are protected and how crews are told to respond to smoke.