Incident Overview
During cruise flight, the airplane's engine seized, prompting the pilot to execute a forced landing. While flaring over a baseball field, the airplane collided with poles and came to rest partially inverted.
Maintenance History
The airplane had been operated for approximately 188 hours since its last annual inspection on April 5, 2001, which was about one calendar year before the accident. Following that inspection, repair station personnel responsible for maintaining the aircraft for the pilot-owner recorded in the maintenance logbook that emergency airworthiness directive (AD) number 2000-18-53 was not applicable. This entry was erroneous; the repair station failed to recognize that the AD was relevant to the oil filter converter plate gasket that had been installed in the engine. The AD required, in part, that the gasket be replaced on a recurring 50-hour basis.
Airworthiness Directive Details
The FAA stated that gasket replacement was warranted because "...protruding or swelling of the gasket allows oil to leak from between the plate and the accessory housing. This condition, if not corrected, could result in complete loss of engine oil and subsequent seizing of the engine...."
Post-Accident Examination
During the Safety Board investigator's examination of the airplane, only 8 ounces of oil were found in the 8-quart capacity oil sump, and the bottom of the airplane was oil soaked. The oil leak originated from a breach in the oil converter plate gasket. A 3/4-inch-long section of the gasket material was observed protruding from between the plate and the accessory housing.
Engine Seizure Cause
The engine's seizure was attributed to the loss of engine oil emanating from the extruded converter plate gasket, resulting in lubricating deprivation to the internal reciprocating components.