Cessna 152 N28BA accident near Wimauma, Florida

Probable cause

The mechanic/pilot's failure to detect a visible exhaust gas leak and cracked cylinder head immediately prior to the accident flight, which resulted in a partial loss of engine power during initial climb. Contributing to the accident was an inadequate 100-hour maintenance inspection, which also failed to detect a visible exhaust gas leak.

NTSB analysis

During initial climb from the airstrip, about 300 feet above ground level, the mechanic/pilot heard a loud noise, followed by a partial loss of engine power. He leveled the nose and verified that the throttle lever was in the full forward position; however, he was unable to maintain altitude. During the subsequent forced landing to a field, the airplane struck a fence. According to the pilot, another pilot who flew the airplane previously reported a rough running engine and had to perform an uneventful precautionary landing to an airstrip. Examination of the wreckage revealed that the No. 2 top spark plug and its associated heli-coil had separated from the cylinder. Further examination revealed that the spark plug and cylinder threads were worn and an approximate 2-inch crack originated near the cylinder head threads. Additionally, the area around the top and bottom spark plug holes exhibited evidence of exhaust gas leakage, which would have most likely been visible during the most recent maintenance inspection. At the time of the accident, the airplane had been operated about 77 hours since its most recent 100-hour inspection, which was completed about 3 months prior to the accident. The No. 2 overhauled cylinder had been operated for 832 hours since it was installed, about 4 years prior to the accident.

Text from the NTSB. Open the NTSB docket for ERA11LA103 for the full record.