History of the Flight
On 1 June 2005, a Piper PA-22-150, registered ZU-AKE, departed Empangeni Aerodrome on a visual flight rules training flight with an instructor and a student pilot. The intention was to return to Empangeni. During the power check and initial climb, the pilot noted engine revolutions per minute (RPM) at 2 300. After levelling off at 1 500 ft above ground level, approximately 3 nm from the aerodrome, a loud bang was heard from the engine. Oil began streaming from the engine, and smoke entered the cockpit, followed by a complete engine stoppage. The pilot elected to perform a forced landing in a sugarcane field east of Empangeni.
Landing and Damage
On touchdown, the aircraft struck an irrigation ditch, bounced, and rotated through 90° before coming to rest facing west. The aircraft sustained damage to the nose wheel, main landing gear, propeller, engine mountings, cowling, fuselage, and both wings. Both occupants were uninjured.
Investigation Findings
The investigation determined that the number 2 cylinder head had fractured due to a fatigue crack that had been present for an extended period. The fractured cylinder head was sent to the University of Pretoria for metallurgical analysis, which concluded that the crack propagated under low-stress conditions, likely over a significant service duration. The aircraft did not have a valid Authority to Fly Certificate at the time of the accident. Additionally, not all required documentation was aboard, and the aircraft lacked a visible serial number. The flight was not conducted under an approved training organisation as required by regulations, although both pilots held valid licenses.
Probable Cause
The probable cause was an unsuccessful forced landing as a result of an engine failure, with the contributory factor being the fracture of the number 2 cylinder head during flight, leading to loss of oil pressure and engine failure.