What happened
On January 1, 2025, at approximately 09:15 UTC, a Textron Aviation Inc. 172N, registration TC-MFD, was conducting a solo navigation flight as part of a training program. The flight originated from Uşak Airport (LTBO) with a planned destination of Denizli Çardak Airport (LTAY).
While en route near the Çal district of Denizli, the student pilot noticed the aircraft was approximately 400 feet below the required altitude. In an attempt to regain altitude, the pilot increased throttle power and simultaneously turned off the carburetor heat to boost engine performance. This action triggered a loss of engine power, followed by a complete engine failure at approximately 6,000 feet. The pilot executed an emergency landing in an open field. Due to the soft, muddy nature of the terrain, the nose gear sank upon impact, causing the aircraft to nose over.
The investigation
The UEİM investigation examined the aircraft's maintenance records, flight data from the HATS system, and cockpit camera recordings. Investigators also reviewed the pilot's medical records, including a toxicology report, and interviewed the student pilot. The investigation also looked into the flight organization's pre-flight procedures and the pilot's physiological state prior to the flight.
Findings
- The investigation established that the engine failure was caused by carburetor icing, which occurred when the pilot deactivated the carburetor heat while increasing power in cold atmospheric conditions.
- The student pilot failed to properly analyze the developing engine power loss and did not adequately assess the impact of the meteorological conditions on the aircraft systems.
- The student pilot was experiencing fatigue, having arrived at their residence in Isparta at 02:30 UTC following New Year's Eve celebrations and departing for the airport at 05:30 UTC.
- The flight organization's flight control officer did not sufficiently evaluate the student pilot's fatigue levels during the pre-flight document check.
- The aircraft was found to be in good maintenance standing, with all required inspections and airworthiness directives up to date. The weight, balance, and fuel levels were all within safe limits.
- There were no injuries to the pilot, and the aircraft sustained light damage to the nose gear, propeller, engine, wings, and tail.