Investigation Summary
The flight was a domestic scheduled service from Tehran to Khorramabad. The aircraft involved, a Tupolev Tu-154M manufactured in 1991, had accumulated 12,701 total airframe hours and 5,516 cycles at the time of the accident. As the aircraft approached its destination, the region was experiencing significant adverse weather, including dense fog, rain, and snow. The crew was cleared for a non-precision approach to Khorramabad Airport. During the descent, the aircraft strayed from the intended flight path, ending up approximately 3 nautical miles left of the extended runway centerline. The crew continued to descend below the safe minimum sector altitude for the mountainous terrain. The Tupolev Tu-154M impacted the snow-covered Sefid Kouh mountain at an elevation of approximately 9,100 feet. Search and rescue efforts were severely hampered by the rugged terrain and continuing blizzard conditions, with the wreckage only being located several hours after the disappearance.
Final Conclusions
The primary cause of the accident was Controlled Flight Into Terrain (CFIT). Contributing factors included the crew's decision to continue the approach in weather conditions below established minima, poor cockpit resource management, and a lack of situational awareness regarding their proximity to the mountain peaks during the descent.
Video Analysis
No video analysis linked for this case file yet.
Systems & Failure Modes
Ground Proximity Warning System (GPWS)
The system designed to alert pilots of imminent terrain impact. In this event, the system failed to prevent the crash as the crew either ignored the warnings or the lack of modern terrain mapping in the older Russian unit provided insufficient lead time in the steep terrain.
Non-Precision Approach
An instrument approach that provides lateral guidance but no electronic glide slope, requiring pilots to manually manage descent altitudes.
Interesting Facts
- 01The accident was the deadliest aviation disaster in Iran at the time of the occurrence.
- 02Among the passengers were four deputy ministers from the Ministry of Roads and Transportation and at least four Spanish nationals.
- 03The aircraft was a Russian-built Tupolev Tu-154M, which was a common type in the Iran Air Tours fleet.
- 04The crash site was located at an altitude of 9,100 feet in the Sefid Kouh mountains.
- 05Rescue teams had to use helicopters and mountain guides to reach the site due to heavy snow and steep terrain.
- 06Early news reports immediately following the crash provided varying fatality counts, ranging from 117 to 118, before the final manifest confirmed 119 victims.
Safety Actions & Advisories
Enhanced Training
Recommendations were made to improve pilot training regarding non-precision approaches in mountainous terrain and strict adherence to minimum descent altitudes.