On May 28, 1991, a Gulfstream American AA1A (registration N5675L) operated by Fireside Gallery, Inc. was involved in an aviation accident near Evansville, IN. Investigators recorded the probable cause as: THE FAILURE BY MAINTENANCE PERSONNEL TO IDENTIFY THE PROPER REPLACEMENT CYLINDER. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A single-engine airplane experienced decreasing engine RPM and power during initial climb, leading to an off-airport forced landing. Post-accident examination revealed a mismatched cylinder bore size.
Accident Summary
A single-engine airplane departed on its first flight following maintenance that included replacement of a cylinder. As the aircraft passed through 200 feet during the climb, the pilot in command observed that engine RPM and power were decreasing. Unable to return to the departure airfield, the pilot performed an off-airport forced landing.
Investigation Findings
Examination of the engine after the accident disclosed that the replacement cylinder was used and had a standard size bore. In contrast, the remaining cylinders and all pistons were 0.010 inch oversize. The mismatch in bore sizes between the replacement cylinder and the other cylinders was identified as the issue.