What happened
On the date of the accident, an aircraft was performing a scheduled charter service for the National Petrochemical Company. The flight was operating a route originating in Bandar-e Mahshahr with a final destination of Tehran. The aircraft was carrying a total of 35 passengers and 4 crew members.
During the cruise phase of the flight, the aircraft encountered extremely severe weather conditions. While navigating through these atmospheric disturbances, the aircraft entered an uncontrolled descent. The flight ended when the aircraft impacted the ground in the vicinity of Saveh.
Findings
All 39 occupants on board the aircraft, including both the crew and the passengers, were killed in the impact. The primary factor identified in the sequence of events was the uncontrolled descent occurring while the aircraft was operating within very bad weather.