ERA16LA235

The student pilot took off for the solo flight. At 400 ft above ground level, the engine sputtered and experienced a total loss of power. The student pilot conducted a forced landing to a golf course. During the rollout, the airplane clipped trees and struck a small berm, which resulted in the collapse of the nose landing gear and substantial damage to the engine firewall. Examination of the airplane revealed severe impact damage on the dome of the engine's No. 3 piston and the cylinder head. The exhaust valve was separated at the stem, and the intake valve was fractured. Fracture analysis of both valves and their associated fragments revealed a fatigue failure of the exhaust valve stem transition area at the valve head. The other fracture surfaces were consistent with overstress. The fatigue failure of the No. 3 cylinder exhaust valve led to the total loss of engine power.

On June 29, 2016, at 1930 eastern daylight time, a Cessna 150L, N1567Q, experienced a total loss of engine power and was substantially damaged during a forced landing after takeoff from Atlanta Regional Airport (FFC), Peachtree City, Georgia. The student pilot was not injured. Visual meteorological conditions prevailed, and a visual flight rules flight plan was filed for the solo instructional flight, which was conducted under the provisions of 14 Code of Federal Regulations Part 91.In a telephone interview, the pilot stated that she performed the preflight inspection, engine start, run-up, and takeoff from runway 31 with no anomalies noted. At 400 ft above ground level, the engine "sputtered, and then stopped." The pilot selected a golf course for the forced landing, and touched down on a slightly rolling fairway lined with trees. During the rollout, the airplane clipped trees and struck a small berm, which collapsed the nose landing gear. Examination of the airplane by a Federal Aviation Administration (FAA) inspector revealed substantial damage to the engine firewall. The engine was rotated by hand at the propeller. The magnetos produced spark at all eight spark plugs. A compression check was performed, and thumb compression was confirmed on all but the No. 3 cylinder. The No. 3 cylinder was removed, and severe impact damage was noted on the dome of the piston and the cylinder head. The exhaust valve was separated at the stem, and the intake valve was fractured, with about 50 percent of the valve head separated. Pieces of the valve were recovered in the exhaust manifold. Both valves and their associated fragments were forwarded to the NTSB Materials Laboratory in Washington, DC for examination. Fracture analysis of the No. 3 cylinder exhaust valve revealed fatigue failure of the valve stem transition area at the valve head. The remaining fracture surfaces observed on the valves were due to overstress. The pilot held an FAA student pilot and third-class medical certificate, issued on December 22, 2015. She reported 41 total hours of flight experience, of which 38 were in the accident airplane. The two-seat, single-engine, high-wing airplane was manufactured in 1971 and was equipped with a Continental O-200 series engine. The airplane had been operated for about 410 hours since its most recent annual inspection was completed on July 5, 2015, at 3,488 total airframe hours.