What happened
On September 15, 2010, at approximately 20:30 UTC, a Cessna 152, registration PT-FCA, departed from Bacacheri Aerodrome in Curitiba, Paraná, for a local flight training mission. The crew, consisting of an instructor and a student pilot, had completed a lengthy pre-flight briefing and intended to perform maneuvers followed by touch-and-go landings.
Shortly after takeoff, as the aircraft reached an altitude of approximately 300 feet, the engine suffered a sudden loss of power. The instructor took control of the aircraft and initiated emergency procedures, including an attempt to restart the engine in flight. When the restart attempt failed, the instructor executed a forced landing on a dirt surface at the Jóqueito Clube do Paraná. Both occupants of the aircraft emerged uninjured, and the aircraft sustained no damage.
The investigation
CENIPA investigators examined the engine to determine the cause of the power loss. While there were no visible external signs of cracks or oil leaks, the engine was found to be seized. Upon disassembly, investigators discovered that the second bearing had become misaligned, which obstructed the oil passage from the engine block to the crankshaft.
A fracture and subsequent separation of a fragment caused the bearing to shift from its original position, blocking the lubrication orifice. This lack of lubrication led to extreme friction and overheating between the bearing and the crankshaft, resulting in the deformation of the bearing and the eventual seizure of the engine.
At the time of the incident, the engine had completed 13,457 total hours, with 2,159 hours flown since its last overhaul. While the engine was within its 2,400-hour overhaul interval, investigators could not determine if the bearings had been correctly replaced during the previous overhaul or if all maintenance procedures had strictly followed the manufacturer's manual.