Accident Overview
On August 21, 2010, about 1210 eastern daylight time, a Piper J3C-65, registration N209RC, operated by a private individual, sustained substantial damage during a forced landing shortly after takeoff from Southern Cross Airport in Williamstown, New Jersey. The aircraft impacted a parked car that was adjacent to a house. Visual meteorological conditions prevailed, and no flight plan was filed for the personal flight conducted under 14 CFR Part 91. The private pilot, the sole occupant, received minor injuries. The car was unoccupied.
Preflight and Takeoff
The pilot reported that the airplane had not been flown recently. He performed two preflight inspections, an engine run-up, and two full-power takeoff test runs during which the airplane became airborne briefly with no discrepancies noted. Following these tests, the pilot taxied to the approach end of runway 27 and slowly advanced full throttle for takeoff. The airplane accelerated and became airborne at the same point along the runway as during the test runs.
Engine Power Loss and Forced Landing
During the initial climb while maintaining the runway heading, the pilot noticed that the engine suddenly ceased developing full takeoff power. He quickly scanned the cockpit to confirm the fuel selector was on, the carburetor heat was off, and the throttle was full forward. As airspeed and altitude decreased, the pilot was uncertain whether the airplane could clear powerlines at the departure end of the runway. Being too far down the runway to abort, he continued flying, cleared the powerlines, and maneuvered for a forced landing in an adjacent field. The airplane then clipped the tops of trees and impacted the unoccupied parked car. After impact, the pilot exited the airplane and awaited rescue services.
Postaccident Examination
Postaccident examination by an FAA inspector revealed that the fuel tank was nearly full of 100 low lead fuel with no contaminants found in the tank or fuel strainer. The carburetor, which had separated on impact, was inspected and showed no discrepancies. The engine exhibited crankshaft, camshaft, and valve train continuity; compression testing of all cylinders revealed no discrepancies. No ferrous particles were noted in the engine oil. Operational testing of the spark plugs using 80 psi as a reference indicated a weak spark from both plugs of the No. 1 cylinder. The lower plugs of the remaining cylinders were found oil soaked and tested below the normal range. The FAA inspector noted that the cylinders were last replaced in 2006, and at the time of the accident the engine had accumulated approximately 6 hours since that replacement.