In a number of investigations into aviation accidents, the conclusions of the IAC were disputed. Among them are such tragedies as the death of the Lokomotiv hockey team in 2011 during takeoff at an airport near Yaroslavl and the tragedy with the plane of Polish President Lech Kaczynski and a high-ranking Polish government delegation when landing at an airfield near Smolensk in 2010. The book outlines the circumstances that raise doubts about the IAC's conclusion. Due to the fact that the former head of the MAK was replaced by a new head, a real possibility arose of an additional investigation into these tragedies.