Accident Details
On January 31, 2021, at approximately 1144 Pacific standard time, a Cessna T182T airplane, registration N291FR, was substantially damaged during a forced landing near Crescent City, California. The flight instructor and pilot-rated student sustained minor injuries. The flight was conducted as a Title 14 Code of Federal Regulations Part 91 instructional flight.
Sequence of Events
During the flight, the flight instructor observed a flashing red turbine inlet temperature (TIT) warning light. He enriched the fuel mixture, after which the TIT indication returned to normal. Shortly thereafter, the engine began to run rough. The instructor switched the ignition to the left magneto, resulting in a total loss of engine power. Switching to the right magneto caused the engine to continue running roughly. Returning to the both magnetos position did not resolve the rough operation. The instructor then adjusted the mixture and activated the auxiliary fuel pump, but these actions failed to restore sufficient engine power to maintain altitude. Locating an open field, the instructor initiated a forced landing. The airplane landed in marshy terrain and nosed over during the landing roll.
Postaccident Examination
Postaccident examination of the engine revealed that the magnetos would not produce a spark. Corrosion was found on internal components of both magnetos. It was also noted that the pressurized magnetos were not equipped with a moisture trap or filter. Disassembly of the magnetos disclosed corrosion and rust on interior surfaces and components. The ignition points were removed, and corrosion was visible on their contact surfaces. Sandpaper was used to clean both sets of points, revealing deformities such as deterioration and buildup on the contact surfaces. After reinstalling the points, neither magneto produced a spark when bench-tested.
The magneto capacitors were bench-tested and both failed under normal testing. An ohmmeter applied to each of the four point assemblies showed inconsistent resistance on the high points of each point. When a used set of points and capacitors (with approximately 500 hours of operation) were installed, the magnetos produced a normal spark on the test bench.
Maintenance History
According to maintenance records, both magnetos were replaced with newly overhauled units on February 1, 2019, at an aircraft total time of 1,248.8 hours. The last annual inspection was performed on November 10, 2020, at an aircraft total time of 1,704.5 hours. The accident occurred 82 hours of operation after that inspection. At the time of the accident, the magnetos had accumulated 537 hours of operation since installation.