NTSB

The pilot’s inadequate compensation for the wind conditions and failure to maintain directional control. The gusting crosswind conditions and the snow covered ground were factors.

Fuel exhaustion due to the inadequate preflight planning and preparation by the pilot in command. Additional causes were the inadequately planned approach and improper emergency procedure by the pilot.

The structural failure of the wings for undetermined reasons.

The aircraft’s encounter with a deer during landing

A missed approach not performed by the pilot and the directional control not maintained by the pilot during landing. Contributing factors were the crosswind, unavailability of wind information due to inoperative meteorological equipment, and a NOTAM not issued by airport personnel indicating that the meteorological equipment was inoperative.

The pilot’s failure to maintain clearance from the terrain during low-level maneuvering at night. Factors included the pilot’s improper in-flight decision to continue into an area that was forecast possibly to contain snow, fog and low ceilings, his failure to obtain a weather update while en route, mountainous terrain, and inadvertent flight into instrument meteorological conditions while on a visual flight rules flight.

The pilot’s failure to maintain Vmc (velocity minimum control) on initial climb, resulting in a loss of control.

The pilot’s failure to preflight the airplane, the pilot’s improper in-flight decision not to expedite the landing, and the inadvertent stall when the pilot allowed the airspeed to get too low. Factors contributing to the accident were the lineman’s improper servicing of the airplane when he left the oil dipstick out and the subsequent oil leak.

The inadequate visual lookout of the pilots in both airplanes, resulting in a midair collision during cruise flight.