NYC98LA168

While at 1,500 feet, the engine developed a slight vibration. The pilot checked the fuel pump on, the mixture rich, and changed fuel tanks. The vibrations increased, and were accompanied by smoke. The pilot heard an explosive 'bang' and the cowling came up into his line of vision. Oil covered the pilot's side of the windscreen, and the engine was unable to maintain altitude. The airplane struck a telephone pole during the forced landing. Post flight inspection revealed a catastrophic failure of the engine's number two cylinder. Factory examination determined that the failure emanated from a rust pit on the outside of the cylinder wall. The cylinder, which was manufactured in July 1996, had 1,780 hours of service.

On August 16, 1998, at 1942 Eastern Daylight Time, a Gulfstream American AA-1A, N9364L, was destroyed during a forced landing near Erial, New Jersey. The certificated commercial pilot received minor injuries. Visual meteorological conditions prevailed at the time of the accident. No flight plan was filed for the flight that departed Ocean City Municipal Airport (26N), New Jersey, about 1800, for Northeast Philadelphia Airport (PNE), Philadelphia, Pennsylvania. The aerial observation (traffic reporting) flight was conducted under 14 CFR Part 91.

The pilot stated that while at 1,500 feet, the airplane's engine developed a slight vibration. He checked the fuel pump on, the mixture rich, and changed fuel tanks. The vibrations increased, and were accompanied by smoke. The pilot heard an explosive "bang" and the cowling came up into his line of vision. Oil covered the pilot's side of the windscreen, and the engine was unable to maintain altitude.

According to a Federal Aviation Administration (FAA) Inspector, the airplane struck a telephone pole during the forced landing. Post-flight inspection revealed a catastrophic failure of the engine's number 2 cylinder.

The cylinder barrel was subsequently examined at the Textron-Lycoming facility in Williamsport, Pennsylvania. It was reported as manufactured in July 1996, with 1,780 hours of service. Inspection revealed a fracture between the first and second cooling fins, which had completely broken through the flange, and spiraled around the barrel. The outside surface of the cylinder, in the vicinity of the fracture, was heavily corroded in areas where paint had flaked off, as well as in areas under the remaining paint. Corrosion pitting was found in some areas up to .004 inches in depth.