Accident Overview
A pilot who had purchased the aircraft earlier in the day departed on a night cross-country flight with two passengers. Shortly after departure, the pilot radioed that he was having electrical problems and needed to return to the airport. During the approach to the runway, the airplane impacted the top of a tree, traveled southward, contacted a wire or cable, and then impacted the ground, coming to rest inverted.
A witness reported that the accident airplane was "very low on approach" and appeared to have "no electrical power," with the engine at a low rpm. The witness also noted that it was hard to determine if the engine was losing power completely.
Examination Findings
On-site examination of the aircraft revealed that the main lead wire to the alternator had separated from the alternator. The wire and its insulated terminal end had disconnected, with the terminal ring remaining on the alternator. Further inspection showed that the terminal had a single pointed style crimp, and the multi-strand wire end that had separated from the terminal ring appeared "weathered." No additional pre-impact mechanical anomalies were found during the on-site examination.
Engine Testing
The engine was subsequently tested at the manufacturer's test cell facility. It was started and run for several minutes at various power settings, from idle to full power. Multiple test runs were conducted, and the engine was able to produce its rated horsepower during these tests.