YAK-Service Flight 9633
Investigation determined that several factors caused the accident. This includes poor training, incorrect calculation of takeoff speed by the flight crew, and bad application of wheel braking by one of the pilots, who had incorrectly placed feet on the pedals. It was later revealed that the pilot had used forged documents to obtain permission to fly the plane, and that both crew members did not have the needed training to fly the Yak-42.