Accident Details
On May 2, 2022, at 1853 eastern daylight time, a Grumman American AA-1C, registration N15LM, was substantially damaged after colliding with trees near Seneca, South Carolina. The pilot, who was the sole occupant, sustained serious injuries. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight.
Preflight and Takeoff
The day before the accident, maintenance personnel at Eagle Ridge Airport (SC24) in Seneca completed the aircraft's annual inspection. On the accident day, the pilot collected the airplane and reported that it had ample fuel, with the fuel selector positioned to the LEFT tank. Before departure, the pilot performed a thorough engine run-up, checking magnetos and oil pressure, both of which were normal. The engine ran smoothly and responded well to full power.
Engine Failure
Shortly after takeoff from runway 23, at approximately 250 feet above ground level, the engine lost power. The airplane descended under control into a wooded residential area about a quarter mile from the departure end of the runway. The pilot could not confirm whether the engine stopped completely before impact, but recalled it did not sputter. The mixture control was at full rich. A witness nearby reported the airplane was low and the engine stopped suddenly without a backfire. First responders detected a fuel odor at the site.
Postaccident Examination
A Federal Aviation Administration (FAA) inspector examined the wreckage and noted substantial damage to both wings and the fuselage. The fuel selector handle, when moved clockwise from OFF to LEFT, did not produce a detent feel or click. However, movement between LEFT and RIGHT did produce a click and detent. The throttle was near idle, mixture near full rich, primer in and locked, and carburetor heat control closed. Magnetos produced spark on all towers and timing was within specifications. The carburetor inlet screen was unobstructed. Fuel samples (consistent with 100LL aviation fuel) were found in various components: about 2 ounces in the carburetor bowl, 1 ounce in the electric fuel pump, a trace in a fractured line to the left wing, and about 1 cup in the right main tank remnants; no fuel was found in the left main tank remnants. Both fuel tanks were breached due to impact, and fuel was uncontaminated.
A subsequent examination arranged by the pilot/owner and conducted by another mechanic (without federal oversight) revealed that the air filter element was out of place inside the carburetor heat box, between the carburetor heat valve and the top of the box. The mechanic believed this would have restricted airflow to the carburetor. Additionally, the carburetor heat control did not operate correctly; when pulled to the ON position, it moved only slightly and then returned to OFF. The same mechanic tested the fuel selector and found it clicked into detent for all positions (LEFT, RIGHT, OFF), and fuel flowed through the valve in both LEFT and RIGHT positions. The electric fuel pump operated and indicated fuel pressure when energized.
Maintenance History
A review of the aircraft's maintenance records for the preceding 3.5 years showed that the air filter was replaced during each annual inspection, including the one performed the day before the accident. There were no recorded entries related to the fuel selector during this period.
Weather Conditions
At 1854, the weather at Oconee County Regional Airport (CEU), Clemson, South Carolina, about 2 miles east of the accident site, reported a temperature of 28°C and a dew point of 13°C, with a calculated relative humidity of about 40 percent. According to the icing probability chart in FAA Special Airworthiness Information Bulletin CE-09-35, these conditions were conducive to serious icing at glide (idle) power.