After washing the airplane, the pilot took off for a short night flight to dry it. Family members reported that the pilot's habit was to do a 15- to 20-minute flight after washing the airplane. A witness near the accident site saw the airplane's nose pointed downward and its red and green position lights spiraling around as it descended. Another witness located closer to the impact location heard loud sustained engine sounds 'like a kamikaze in a dive.' The airplane collided with trees and hilly terrain and the extensively fragmented wreckage was spread over a 100- by 200-foot debris field. The aircraft sounds terminated after a few seconds with the sound of '2 cars hitting each other.' The pilot's last reported flight review was conducted in a helicopter. The last pilot logbook entry was dated May 28, 1997, the date of the last flight review. According to the aircraft logbook, the pilot would have averaged about 1.8 flight hours per month in the airplane during the past 11.5 months. Weather observations reported clear skies with no visibility restrictions. There was no moon illumination. The only ground reference lights were from the city, which was located north and west of the accident site. No preimpact failures or malfunctions were found during the wreckage examination.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:

Index for Sep1998 | Index of months