Date & Time:
Jan 21, 1980 at 1911 LT
Type of aircraft:
Boeing 727-100
Operator:
Registration:
EP-IRD
Flight Phase:
Landing (descent or approach)
Flight Type:
Scheduled Revenue Flight
Survivors:
No
Site:
Mountains
Schedule:
Mashhad - Tehran
MSN:
19817/537
YOM:
1968
Flight number:
IR291
Country:
Iran
Region:
Asia
Crew on board:
8
Crew fatalities:
8
Pax on board:
120
Pax fatalities:
120
Other fatalities:
0
Total fatalities:
128
Circumstances:
On the day of the accident, Iranian air traffic controllers went on strike, which led to hundreds of domestic flights being cancelled. At 1600LT the strike was interrupted and flights resumed. At 1740LT, the airplane departed Mashad Airport on schedule service IR291 to Tehran-Mehrabad Airport with 120 passengers and a crew of eight on board. At 1852LT, ATC based at Tehran-Mehrabad Airport cleared the crew for a direct approach to runway 29. At 1905LT, the dispatcher instructed the crew to take a 360° heading to reach the non-directional beacon of Varamin. On approach, the copilot informed the captain that the VORTAC was giving a wrong radial course but the captain failed to respond to this message. At 1911LT, while descending in limited visibility due to night, snow falls and foggy conditions, the airplane struck the slope of a mountain located in the Alborz Mountain Range. The wreckage was found few hours later in a snow covered terrain about 29 km north of Tehran Airport. The aircraft disintegrated on impact and none of the 128 occupants survived the crash.
Probable cause:
It is believed that the accident was the consequence of a controlled flight into terrain, favored by an inoperable instrument landing system (ILS) of runway 29, when the ground radar was inoperative. The accident occurred just three hours after the Iranian air traffic controllers had resumed work after a strike period till 1600LT. The lack of visibility due to night and poor weather conditions remains a contributing factor.
