N231GGMooney Aircraft M20K · 1979

On January 3, 2024, about 1226 central standard time, a Mooney M20K, N231GG, was substantially damaged when it was involved in an accident near Tullahoma, Tennessee. The commercial pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

The pilot reported that he had recently purchased the airplane and the accident flight was his first flight in the airplane. The accident flight was also the first flight since the airplane’s most recent annual inspection, which was completed the same day. No anomalies were noted during the preflight inspection, engine start, taxi, and engine run-up. The airplane took off uneventfully from runway 36 at Tullahoma Regional Airport (THA), Tullahoma, Tennessee.

The pilot made a right turn southeast for the 20-mile flight back to his home airport, Franklin Country Airport (UOS), Sewanee, Tennessee. The pilot had planned to climb to 4,500 ft mean sea level (msl) for the short flight home. About 3,200 ft msl (2,000 above ground level), the engine suddenly lost all power without any warning. At that time, the airplane was about 4 miles from THA and the pilot turned back to the airport in an attempt to glide to runway 24. He also tried to restart the engine; however, the starter motor would not rotate the propeller. The pilot was unable to glide the airplane to the runway, and it impact hilly terrain about 1/2-mile before reaching the runway.

Examination of the wreckage by a Federal Aviation Administration inspector revealed that it came to rest upright. Both wings and the empennage sustained substantial damage.

Review of maintenance records revealed that the engine had accumulated about 692 hours since its most recent overhaul in 1994. The engine manufacturer recommended overhaul at 1,500 hours of operation or 12 calendar years, whichever occurs first. Additionally, the airplane had not been flown during the 26-month period before the accident flight. The pilot did not purchase fuel before the accident flight and stated that the fuel onboard could have been 2 years old or older.

During recovery, about 16 gallons of fuel (8 gallons per tank) were drained from the airplane’s fuel tanks. The fuel was blue, clear, and consistent with 100LL aviation gasoline. No visible contamination was observed.

The engine was examined following recovery of the airplane. The top spark plugs were removed. Their electrodes were intact and light gray in color. The propeller was rotated by hand. Crankshaft, camshaft, and valvetrain continuity were confirmed to the rear accessory section of the engine and thumb compression was attained on all cylinders. The left magneto produced spark at all leads when rotated by hand. The right magneto would not produce spark when rotated by hand. It was disassembled and no anomalies were noted with the points or rotor. The fuel sump and screen were absent of debris.