NTSB

The student’s failure to maintain the proper glidepath and clearance from terrain and the flight instructor’s delayed remedial action. The flight instructor’s fatigue was a factor.

The pilot’s failure to maintain a proper glidepath to the runway.

The pilot’s failure to maintain directional control during landing rollout. A contributing factor was the passenger’s interference with the pilot’s manipulation of the controls.

The pilot’s continued flight into adverse weather, and his failure to maintain altitude during the instrument approach. The severe icing, moderate turbulence, and low-level wind shear were factors.

The flight instructor’s inadequate compensation for the gusty crosswind conditions.

The passenger’s inadvertent application of the left brake during landing roll, which resulted in a swerve to the left and impact with trees.

The pilot’s failure to maintain an adequate airspeed that resulted in a stall. A contributing factor was the group of trees located near the departure end of the runway.

The pilot’s failure to maintain aircraft control during the missed approach, which resulted in an inadvertent stall and impact with terrain. The ice was a factor.

The pilot’s inadequate compensation for a crosswind during the landing flare, which resulted in a loss of control.