The Accident
The aircraft had not flown for two years. Prior to departure, a mechanic observed evidence of fuel leaking at drain holes in the left wing root, just aft of the main cabin door. The mechanic brought this to the attention of the pilot-rated passenger. Shortly thereafter, the aircraft departed with the pilot (PIC), the aircraft owner, and a passenger/mechanic.
About 14 minutes after takeoff, radar data showed the aircraft transitioning from a climb to a descent while in a 180-degree turn. Witnesses reported seeing smoke and flames trailing from the aircraft. The aircraft subsequently impacted trees and power lines before crashing in a small flat field within hilly terrain.
Post-Crash Examination
Examination of the wreckage revealed melted aluminum spatters on the leading edge and underside of the left horizontal stabilizer. Additionally, 'focalized' fire damage was noted on the cabin behind the drain holes in the left wing root. Toxicology testing detected tetrahydrocannabinol carboxylic acid (marijuana) in the pilot-rated passenger's blood (0.004 ug/ml) and urine (0.010 ug/ml).
Probable Cause
The investigation determined the probable cause of the accident to be: a fuel system leak, inadequate preflight by the pilot (PIC), and by the non-flying pilot/passenger intentionally allowing operation of the aircraft with a known deficiency (fuel leak). A factor related to the accident was the lack of suitable terrain for a forced landing.