Incident Overview
On a dark night with 10 miles visibility, a pilot was conducting a traffic pattern approach to runway 31 at an uncontrolled airport. While descending on base leg, the airplane drifted south of course. The airplane continued its descent and collided with an unmarked hill located approximately 3/4 mile south of the airport.
Pilot Report
The pilot subsequently reported that due to a lack of ground reference, he did not observe the rising terrain or the southerly drift.
Conditions
The approach took place at night with visibility reported as 10 miles. The airport was uncontrolled, and the hill involved was unmarked.
Sequence of Events
The pilot initiated a traffic pattern approach to runway 31. During the base leg descent, the airplane deviated southward. The descent continued until the airplane struck terrain on an unmarked hill south of the airport.