What happened
A local training flight departed from Tehran-Mehrabad Airport, heading south of the Iranian capital. During the cruise phase of the flight, the crew experienced an engine failure and subsequently declared an emergency to initiate a return to the airport.
While performing an emergency descent toward runway 29L, the radome situated on the top of the aircraft became detached and struck the tail section. This structural failure caused the aircraft to become uncontrollable. The plane subsequently crashed into an open field in the vicinity of Varamin. The impact caused the aircraft to disintegrate, resulting in seven fatalities among the occupants.
Findings
Investigations suggest that the radome detached due to the aircraft exceeding its certified speed limits during the emergency descent procedure.