Scandinavian Airlines System Flight 751
| File:Sas flight 751 crash.jpg Dana Viking after the crash. (Copyright: Ola Carlsson) | |
| Occurrence | |
|---|---|
| Date | December 27 1991 |
| Summary | Propulsion loss |
| Site | Gottröra, Sweden |
| Aircraft type | McDonnell-Douglas MD-81 |
| Aircraft name | Dana Viking |
| Operator | Scandinavian Airlines (SAS) |
| Registration | OY-KHO |
| Flight origin | Stockholm-Arlanda Airport |
| Destination | Copenhagen Airport |
| Passengers | 122 |
| Crew | 7 |
| Fatalities | 0 |
| Injuries | 25 |
| Survivors | 129 (all) |
Scandinavian Airlines Flight 751, a McDonnell Douglas MD-81, took off from Stockholm-Arlanda Airport, Sweden, in the early morning of December 27 1991. The airliner was piloted by Danish captain Stefan G. Rasmussen and Swedish first officer Ulf Cedermark. It was headed to Warsaw, Poland through Copenhagen, Denmark.
After 25 seconds of flight, noise and vibrations from the engines were first noticed. The flight crew responded by throttling down, but an automatic system simultaneously increased throttle as a response to increasing altitude. An SAS flight captain, Per Holmberg, who was on board as a passenger noticed the problems early and hurried to the cockpit to assist the crew. Problems with the other engine began 39 seconds later, and finally both engines failed at 76 and 78 seconds into flight, at 3000 feet of altitude.
The pilot responded to the engine loss by pitching the aircraft down before leveling it, to try and make the aircraft glide the longest possible distance without stalling. The pilots requested a return to Arlanda and attempted the restart procedure,[1] but with the plane breaking through the cloud cover at 600 feet, the pilot chose an opening in the forest, near Vängsjöbergs säteri in Gottröra, Uppland, for the immediate emergency landing.
The plane hit the trees before touching down, losing a large part of the right wing. The plane broke into three parts before coming to a stop on the field. 25 people were injured, two of them seriously. Nobody died in the accident, which is known in Sweden as Gottrörakraschen (the Gottröra crash). One of the reasons for the lack of deaths was the brace position.
The crash was later found to have been caused by ice from the wings which had entered both rear-mounted engines, known as Foreign Object Damage. Apparently the maintenance crew had failed to notice the ice which had formed during the night before when temperature decreased below freezing point. The flight crew received praise for the skilled emergency landing in a potentially fatal situation.
Another contribution to the accident was insufficient training of the crew for this particular aircraft: they were not informed about an automatic thrust system (ATR for Automatic Thrust Restoration), and they were not trained in restoring engine operation after they repeatedly surged.[2] The reason they were not informed were that McDonnell Douglas had not informed SAS that the ATR system was installed.[2]
After the Gottröra accident, airports and airlines operating in cold regions had to re-evaluate and modify their deicing procedures.
External links and references
- ^ Cockpit Voice Recorder transcript for SK 751 Hosted at aviation-safety.net
- ^ a b Accident description at the Aviation Safety Network