6. The accident location was in a mountainous area seven and one-half miles southeast of Half Moon Bay at an elevation of 1,950 feet MSL.
7. The weather conditions in the area precluded an approach by means of visual reference to the ground.
8. The time element involved would not have permitted the aircraft to have flown from Half Moon Bay Fan Marker to the ILS outer marker and then execute the CAA approved instrument approach procedure.
9. The undestroyed wreckage yielded no evidence of mechanical or structural failure of the aircraft prior to impact.
Probable Cause
The Board determines the probable cause of this accident was the failure of the crew to follow prescribed procedures for an instrument approach.
BY THE CIVIL AERONAUTICS BOARD:
/s/ CHAN GURNEY
/s/ HARMAR D. DENNY
/s/ OSWALD RYAN
/s/ JOSH LEE
/s/ JOSEPH P. ADAMS
