The Civil Aviation Organization of Iran concluded that a possible pilot error was the cause of the Aseman Airlines crash that killed 66 people last February.
On February 18, an ATR 72-500 plane and registration EP-ATS crashed in a mountainous area of the Province of Isfahan, in northern Iran.
The aircraft operated flight 3704 from the Tehran Mehrabad International Airport (THR), to the Yassuj Airport (YES). Its 66 occupants, 60 passengers and 6 crew (2 pilots, 2 flight attendants and 2 security personnel), died on the site.
A report from the Civil Aviation Organization reported that the accident was probably caused by a pilot error.
Although a final conclusion was not yet released, some precisions were published: The team showed that the pilot descended to 17,000 feet as indicated by the control tower, but later continued to descend to 15,000 and 14,000 feet, action that is against the aeronautical regulations of the country.
When the Aseman Airlines plane was flying at 14,000 feet, the pilots activated the autopilot and the aircraft continued to descend. Moments later the alarms of proximity to the ground sounded, but they were ignored by the pilots.
The report points to another factor that makes the pilot responsible. He had medical restrictions to fly the plane and Aseman Airlines ignoring the situation, allowed him to fly.
The investigation also showed that the warning system that warns about ice on the wings and the fuselage was faulty, which is why the pilots could not control the plane either.