Accident Details
On March 30, 2022, about 1330 mountain standard time, an experimental amateur-built Cozy Mark IV airplane, registered N294MV, was substantially damaged when it impacted trees short of the runway threshold near Tucson, Arizona. The pilot, who was the sole occupant, sustained minor injuries. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight.
Pilot Report
The pilot reported that during the base turn to final, while descending at idle power, he noticed the alternator indicator light flashing and observed no indications of engine rpm or manifold pressure. He noted no roughness or abnormal noise associated with the power loss. The pilot immediately switched fuel tanks, confirmed the boost pump was on, and observed that the propeller was not windmilling. He attempted an engine restart but was unsuccessful. The airplane then struck trees approximately 1,000 feet short of the runway threshold, resulting in substantial damage to both wings.
Postaccident Examination
Postaccident examination of the engine revealed no evidence of preimpact mechanical malfunctions or failures that would have precluded normal operation. Examination of the fuel system found a clogged fuel filter on the left fuel line from the left fuel tank to the engine. The fuel filter on the right fuel line also had contamination but was only partially clogged. The pilot stated that he had the left fuel tank selected at the time of the accident and normally selects it while flying in the traffic pattern.
A sample of the material that clogged the left fuel filter was sent to the National Transportation Safety Board Materials Laboratory for analysis, along with samples of two types of foams and uncured sealant material used in building the airplane. Spectrum analysis determined that the clogging material was consistent with an epoxide. A spectral library search found matches to several epoxy resins and sealants. However, the clogging material did not match any of the samples submitted for comparison, including the uncured sealant sample. The clogging material was noted to have cured based on its appearance and the similarities to the spectral matches found in the library search.