NTSB

Probable cause: The pilot’s failure to properly secure the portable GPS and antenna cable, which resulted in the inadvertent landing gear retraction during landing.    

Probable cause: The pilot’s improper landing flare, which resulted in a hard landing.

Probable cause: The glider pilot’s failure to maintain pitch during a CG aerotow, which resulted in the loss of control of the tow airplane.

Probable cause: The pilot’s selection of an unsuitable snow-covered airstrip for landing, which resulted in a nose-over.

Probable cause: The student pilot’s failure to relinquish flight controls and premature flap reduction during approach to land.

Probable cause: The pilot’s exceedance of the airplane’s critical angle of attack during takeoff, which resulted in an aerodynamic stall.

Probable cause: The pilot’s failure to maintain clearance from a tree while on approach to land.

Probable cause: The pilot under instruction’s failure to extend the landing gear and the flight instructor’s inadequate supervision and failure to ensure that the landing gear was extended.