WPR10LA477

While in cruise flight, the airplane's engine began to lose power and eventually stopped running. The pilot performed a forced landing in a field. During the landing roll, the airplane impacted a fence, substantially damaging the airframe and wings. According to the pilot, the airplane's two-cycle engine is designed to receive lubrication to the piston via engine oil premixed into the automobile gasoline. A postaccident examination of the engine revealed excessive carbon buildup on the piston rings, which more than likely reduced the lubrication between the piston rings and the cylinder wall and led to overheating and a subsequent seizure of the engine.

On September 28, 2010, about 1120 Pacific daylight time, an experimental Eccker Hurricane Hauler, N7519W, impacted a baseball field backstop during a forced landing near Jamul, California. The sport pilot, who was the sole occupant of the airplane, received minor injuries, and the airplane, which was owned and operated by the pilot, sustained substantial damage to its airframe and wings. The 14 Code of Federal Regulations Part 91 personal pleasure flight, which departed Nichols Field, near San Diego, California, about 20 minutes prior to the accident, was being operated in visual meteorological conditions. No flight plan had been filed. According to the pilot, during cruise flight the engine started to lose power, and eventually the propeller stopped rotating. He therefore executed a power-out forced landing in the playground of a nearby primary school. Although the touchdown was successful, during the landing roll the airplane slid on the damp grass as the pilot tried to apply braking, and eventually it impacted a chain link fence around a baseball field, before the pilot could get it to come to a complete stop. After the accident, the pilot received permission from the NTSB Investigator-In-Charge (IIC) to disassemble the 2-cycle Rotax engine in order to look for internal failures or anomalies. According to the pilot, there was a heavy accumulation of carbon on the piston rings, which normally receive their lubrication from the 50 to 1 ratio of 2-cycle oil premixed in the gasoline by the pilot. Reportedly, the carbon build-up and a subsequent lack of lubrication resulted in seizure of the engine. Although the pilot felt that the brand of automobile gasoline he was using may have contributed to the carbon build-up, that could not be confirmed. It also could not be confirmed that the pilot had mixed the correct ratio of 2-cycle oil into the gasoline, although he said he had done so.