On February 18, 1995, at 2000 Pacific standard time, a Cessna 182C, N9036T, owned and operated by the pilot, collided with a hill on the base leg to runway 31 at Gnoss Field, Novato, California. The airplane was substantially damaged. Neither the commercial pilot nor passenger were injured during the nighttime personal flight. The flight originated from Stockton, California, at 1915. On February 18, 1995, the pilot reported to the National Transportation Safety Board that no mechanical problems were experienced during the flight. The pilot indicated that he did not recognize he was low during the approach, and the airplane collided with a ridge about 3/4 mile south of the runway. On March 8, 1995, in the pilot's completed "Aircraft Accident Report," NTSB Form 6120.1, he reported that at the time of the accident it was a dark night, the sky was clear, and the visibility was about 10 miles. The pilot further reported that approaching the airport he may have encountered a "southerly drift" and "sinking air" which put him off course. Also, because there was a "lack of ground reference", the rising terrain was obscured.