NTSB Probable Cause

THE PILOT'S FAILURE TO MAINTAIN THE PROPER ALTITUDE, HIS IMPROPER INFLIGHT DECISION TO ATTEMPT FLIGHT BELOW THE BASE OF AN OVERCAST LAYER OF CLOUDS TOWARD RISING MOUNTAINOUS TERRAIN AND THE FLIGHT'S INADVERTENT ENTRY INTO INSTRUMENT METEOROLOGICAL CONDITIONS. FACTORS WHICH CONTRIBUTED TO THE ACCIDENT WERE THE PILOT'S MISJUDGED WEATHER EVALUATION AND HIS IMPROPER VFR PROCEDURES.