20250920012899A

During an IFR training session while at cruising altitude of 7,000 feet, the pilot in command (PIC), who is also a certified flight instructor (CFI), detected an unexpected drop in engine RPM by approximately 100. Based on the PIC in his written statement, he activated the carburetor heat, but the engine RPM continued to decrease to 1,400, fluctuating between 1,400 and 2,000 RPM. The engine's pulsating behavior did not produce any unusual noises. The aircraft began an unplanned descent, prompting the PIC to declare an emergency with bradley air traffic control (bdl ATC). Bdl ATC advised the PIC of the nearest airport, great barrington (kgbr), 20 miles to the north. However, the PIC deemed it unreachable and opted to attempt an emergency landing at a visible racetrack below. Based on the pic's statement he followed the "rough running engine in flight" checklist, provided by the flight school – usaa 172 carbureted checklist revision 3 dated 5/1/2025. The steps included: setting the throttle to full. Ensuring the carburetor heat was on. Adjusting magnetos for best power by trying different settings. Adjusting the mixture from lean (for cruise) to full rich and other settings to restore power, but without success. At 3,500 feet, when the engine stopped running entirely, the PIC stated he executed the "engine failure during flight (restart)" checklist: achieved best glide speed. Carb heat on. Checked fuel selector positions (both, left, and right) for approximately 30 seconds each with no avail. Mixture set to rich. Verified the primer was in and locked. Ensured the ignition switch was set to both. The checklist failed to restart the engine, necessitating an emergency landing. At 1,700 feet, the PIC stated he was committed to landing at the racetrack, executing the "emergency landing without engine power" checklist: secured seats, belts, and shoulder harnesses. Set the mixture to idle cutoff and turned off the fuel selector and ignition switch. Deployed full flaps and turned off the master switch. Lastly, unlatched the doors for quick egress. The aircraft executed a short-field landing resulting in a touchdown point on asphalt, transitioning onto grass before encountering a fence and guardrail. The distance from the point of tire marks to the guardrail is 324 feet. The wire fencing and ten associated wooden poles suffered damage, but the guardrail remained intact. This sequence resulted in: detachment of the nose landing gear and collapse of the left main landing gear. The aircraft came to rest just beyond the guardrail, listing to the left with the left-wing tip contacting the ground and the lower engine cowling embedded in the dirt. Significant structural damage was noted, especially around the landing gear mounts and lower fuselage. The left-wing tip leading edge upper and lower skin are buckled and possible main spar damage. Four engine mount support tubes are bent, and the exhaust and induction systems are damaged. Fuel samples from the wing tanks and carburetor are consistent with uncontaminated 100LL aviation fuel. The aircraft had approximately 29 gallons of fuel remaining, and consumption calculations suggested an adequate fuel supply for the flight duration. The Lycoming O-320-E2D engine, with 833.4 hours’ time since major overhaul (tsmo), showed no visible mechanical failures, although engine mounts and associated components were damaged upon impact. The engine oil was evaluated and measured to have 7 of an 8-quart capacity and was recorded in the logbooks to have been replaced at the previous 50-hour inspection 41.7 hours earlier. The propeller shows no visible damage other than the spinner cone having a large dent on the underside; it was manually manipulated and found to be free of movement with slight resistance depicting normal compression from the internal mechanism of the engine. The PIC reported no injuries, while the pilot in training sustained a minor head laceration and was hospitalized for observation.