More than a dozen of different factors might have caused the crash of Tu-154 aircraft, but the most of the issues were on the Polish side, said Edmund Klich, the head of the Polish investigative commission.

Klich pointed out the low level of pilots’ training, non-sufficient preparation for the flight and willingness to violate rules. He also called “totally irrational” the pilots’ attempt to land in dense fog, Mig News reported.