Accident Details
On October 18, 2018, at approximately 1057 eastern daylight time, a Cessna 172S, registration N924MM, was substantially damaged during a forced landing following a partial loss of engine power after takeoff from Lynchburg Regional Airport (LYH) in Lynchburg, Virginia. The flight instructor and student pilot on board were not injured. The aircraft was operated by Liberty University under Title 14 Code of Federal Regulations Part 91 as an instructional flight. Visual meteorological conditions prevailed, and no flight plan was filed for the local flight.
Flight Sequence
The flight instructor, seated in the right cockpit seat, reported that all ground operations were normal, including pretakeoff engine indications. The student pilot performed the takeoff on runway 4. After the flaps were retracted, at an altitude of about 200 feet above ground level, they noticed an engine vibration and the airplane shuddered. Engine RPM decreased with degraded performance. The flight instructor took control and observed that airspeed had dropped to just above stall speed, accompanied by the stall warning horn. He lowered the nose to prevent a stall and attempted to land on intersecting runway 35. The airplane touched down with approximately 100 feet of runway remaining. Realizing that stopping within the remaining runway was not possible, the instructor steered the airplane to the right to avoid a steep drop-off under the extended centerline of the runway. The airplane departed the runway surface, struck a drainage ditch, and came to rest in a nose-down position in the grass. The pilots egressed and were met by first responders.
Post-Accident Examination
A Federal Aviation Administration inspector examined the wreckage. The outboard portion of the left wing sustained structural damage during the landing, and the propeller struck the ground. An engine examination was performed after recovery. A cylinder pressure/leak check with 80 psi input pressure showed readings of 74, 74, and 78 psi for cylinders No. 1, 3, and 4, respectively. The No. 2 cylinder read 22 psi, and its spark plugs were oil soaked. The No. 2 exhaust valve was found stuck open, with air audibly escaping past the valve. No cracks or leaks were observed in the cylinder body. The engine had accumulated 2,106 hours since overhaul, while the manufacturer's recommended overhaul interval was 2,200 hours.