What happened
On June 12, 2023, a Cessna R182, registration N3138C, was involved in an accident near McCall, Idaho. The flight was being operated as a private, non-commercial flight under Part 91 regulations. The pilot and passenger had arrived at McCall Municipal Airport (MYL) the previous evening and intended to fly a short distance to Indian Creek, Idaho, the following morning.
During the takeoff roll from runway 34, the pilot noted a slight tailwind. As the aircraft rotated, the pilot reported a power problem. Although the pilot attempted to return to the runway, the aircraft failed to gain sufficient altitude to clear trees located at the departure end of the runway. Witnesses observed an unusually long takeoff roll and noted that while the engine sounded smooth, it was not developing full power. The aircraft impacted the top of a pine tree and subsequently came to rest on its right side. The accident resulted in 1 fatality and 1 serious injury.
The investigation
Investigators examined the engine and found that a single-drive dual (D-style) magneto had been installed approximately 15 hours prior to the accident. While the magneto remained attached to the engine accessory case, it was not securely fastened to its mounting pad. Both the upper and lower retaining hardware were loose, and the lower hardware had backed off approximately 1/4 inch, allowing the magneto to move when manually manipulated.
Maintenance records indicated the aircraft had been brought in for service due to a suspected malfunctioning magneto. The mechanic involved reported that after troubleshooting, a replacement magneto was installed, and engine runs were conducted without further issues. A separate mechanic had performed a quality control check on the work.
Findings
- The engine manufacturer had previously issued a service instruction letter warning that magneto hardware can become loose or unfastened following maintenance due to incorrect installation, improper torquing, or incorrect gaskets/clamps.
- The investigation determined that the magneto's hardware was not properly installed, torqued, or inspected, which led to the loose mounting and the subsequent loss of engine power.