Turkish Airlines Flight 981

**Turkish Airlines Flight 981** was a regular flight operated by Turkish Airlines, from Istanbul to London Heathrow, with a stopover in Paris. On 3 March, 1974, the McDonnell Douglas DC-10 operating the flight suffered an rapid  decompression and crashed into the Ermenonville Forest, shortly after it had left Paris, killing all 346 people on board.  An  after the crash found out that one of the cargo doors at the rear of the aircraft was not properly closed and secured. The implosion also damaged cables needed to fly the aircraft. in 1985, which became the single deadliest aircraft disaster, holding a death toll of 520. The aftermath saw several design changes to the DC-10 to prevent such crashes and renewed scrutiny of the design process.

The accident was the result of the ejection in flight of the aft cargo door on the left-hand side: the sudden depressurization which followed led to the disruption of the floor structure, causing six passengers and parts of the aircraft to be ejected, rendering No 2 engine inoperative and impairing the flight controls (tail surfaces) so that it was impossible for the crew to regain control of the aircraft.

The underlying factor in the sequence of events leading to the accident was the incorrect engagement of the door latching mechanism before take-off. The characteristics of the design of the mechanism made it possible for the vent door to be apparently closed and the cargo door apparently locked when in fact the latches were not fully closed and the lock pins were not in place.

It should be noted, however, that a view port was provided so that there could be a visual check of the engagement of the lock pins.

This defective closing of the door resulted from a combination of various factors:

* incomplete application of Service Bulletin 52-37;
* incorrect modifications and adjustments which led, in particular, to insufficient protrusion of the lock pins and to the switching off of the flight deck visual warning light before the door was locked;
* the circumstances of the closure of the door during the stop at Orly, and, in particular, the absence of any visual inspection, through the view port, to verify that the lock pins were effectively engaged, although at the time of the accident inspection was rendered difficult by the inadequate diameter of the view port.

Finally although there was apparent redundancy of the flight control systems, the fact that the pressure relief vents between the cargo compartment and the passenger cabin were inadequate and that all the flight control cables were routed beneath the floor placed the aircraft in grave danger in the case of any sudden depressurization causing substantial damage to that part of the structure.

All these risks had already become evident, nineteen months earlier, at the time of the Windsor accident, but no efficacious corrective action had followed.

## Passengers and Crew
Of the 346 people on-board, 177 passengers came from the United Kingdom, 48 came from Japan, 45 passengers and 11 crew members came from Turkey, 25 came from the United States, 16 came from France, 10 were from Italy, 9 from Thailand, 7 from Austria, 6 from China, 5 from Hong Kong and Brazil, 4 from Canada, 3 from Argentina, Portugal, Taiwan, and Yugoslavia, 2  from Australia, Hungary, India, Mexico, the Philippines, South Korea, Singapore, and 1 from Belgium, Cyprus, West Germany, Greece, Iran, Israel, Ireland, Morocco, the Netherlands, New Zealand, Pakistan, Portugal, Senegal, South Africa, Spain, Sweden, Switzerland and South Vietnam. 

## Notes
## References 
## Other websites 
* Plane Crash Turkish Airlines flight 981 Dc 10; YouTube