Investigation Summary
The investigation revealed a complex sequence of events starting with severe atmospheric icing. The Boeing 727-200's tail section lacks an anti-ice system, and ice accumulation likely altered the aircraft's aerodynamics, increasing its stall speed. During the missed approach, the stick shaker activated twice. In response to the second stall warning, the crew applied maximum power, but disturbed airflow—likely caused by the high angle of attack and icing—led to engine surges and flame-outs in engines 1 and 3. The crew then retracted flaps while at a low altitude and low speed, which significantly increased the rate of descent. The aircraft struck the ground in a snow-covered field, breaking into several sections.
Final Conclusions
The primary cause was the crew's inadequate handling of the aircraft during abnormal conditions, specifically their failure to follow established procedures for icing and stall recovery. Contributing factors included the aircraft's outdated technology, a lack of simulator training for adverse weather, and poor Cockpit Resource Management (CRM).
Photographic Evidence (1)
Video Analysis
They Aborted the Landing… But the Danger Had Just Begun — An analysis of the crash of Iran Air Flight 277, which went down near Urmia after a double engine flame-out in icing conditions.
If playback is blocked, the owner has disabled embedding — use the link above.
Airframe & Maintenance
Crew Experience
Captain
2,087 hours as captain on type.
First Officer
Flight Engineer
Systems & Failure Modes
Anti-Ice System
The aircraft lacked anti-icing for the tail section, contributing to ice buildup that altered stall characteristics.
Stick Shaker
The stall warning system activated twice during the approach and missed approach phases.
P&W JT8D-15 Engines
Two of the three engines suffered flame-outs due to disturbed airflow and improper throttle management during the stall recovery.
Interesting Facts
- 01Visibility at Urmia Airport was only 800 meters in heavy snow at the time of the accident.
- 02The Boeing 727 tail section does not have an anti-ice system, making it vulnerable to aerodynamic changes in icing conditions.
- 03The aircraft broke into multiple sections upon impact, but there was no post-crash fire.
- 04Rescue efforts were severely hindered by snow depth reaching 70 centimeters at the crash site.
Safety Actions & Advisories
Training Improvements
The investigation highlighted the need for better simulator training specifically for adverse weather and icing conditions.
CRM Emphasis
Recommendations were made to improve Cockpit Resource Management (CRM) and adherence to standard operational procedures during emergencies.