What happened
While approaching Anderson Pass at approximately 7,500 feet MSL, the pilot and four passengers encountered turbulence. During this encounter, the aircraft began to sink. In an attempt to exit the pass, the pilot executed a turn to reverse the direction of flight.
Despite these maneuvers, the aircraft continued its descent. Prior to impact, the pilot applied full flaps. The aircraft struck a glacier while traveling downhill. Upon impact, the wheel/skis separated from the landing gear, and the aircraft nosed over at an elevation of approximately 6,500 feet.
During the period following the accident, while awaiting rescue, the pilot observed that wind gusts from various directions were strong enough to blow pieces of the wreckage uphill.