I read a few things about the plane and incident:
- The Ukranian plane as some mentioned was licensed to be assembled in Iran.
- Initially, the plane did not pass the criteria set by Iranian standard.
- The experts after writing their report were reassigned or relieved from duty resulting the dismissal of the report.
- Later, after additional problems and more accidents the plane was allowed to fly under certain conditions:
a) The TV3 engine used for the Mil choppers, (Mil-17 I believe) was not suited for Iran weather or hot weather and as a result
it was not allowed to fly during high temperature.
b) The allowed weight was drastically reduced due to the inefficient power of the engines in case of an emergency. Seats
were reduced from 50 to 32.
c) Regular checks for fuel system was mandatory as one of problems of the plane was its fuel system.
On the day of the accident, the weather was reported above 40C and the plane over weight (according to the revised SOP for the plane). The notorious fuel system problem plus the hot weather caused the engine to fail and catch fire. The additional weight of the plane didn't allow enough lift and during return for an emergency landing strikes the high voltage cables causing the tail to come off, which after that, no matter how much of a good plane you have, the fate of the flight was doomed.
May the dead rest in peace.
It seems internal Iran politics played a major role in obtaining this aircraft and allowing it to fly after several incidents, which not all ended in crashes and death. Ironically, the head designer or one of the senior engineers of the IrAn-140 died in one of the early crashes! Apparently, the plane has been given the nick name, "Flying Coffin" by some of the pilots. The remaining planes, which there shouldn't be many of them, have been finally grounded.