What happened
On 23 May 2004, a Cessna 172, registration EI-CFP, departed from Weston Airport as part of a training flight. After taking off from Runway 25, the aircraft climbed to approximately 300 feet above ground level. As the pilot leveled the wings following a right turn for noise abatement procedures over the Leixlip reservoir, the engine began to vibrate and lost power.
In response to the engine failure, the pilot aborted the climb and performed a precautionary landing back on Runway 25. The aircraft came to a stop on the runway extension after the pilot applied maximum braking. There were no injuries to the two occupants, and no damage was sustained to the airframe during the landing sequence.
The investigation
The investigation focused on the mechanical state of the engine following the incident. Upon inspection of the aircraft in a hangar, investigators identified a crack in the No. 2 cylinder head, extending from one spark plug to the adjacent exhaust valve. This defect was severe enough to require the removal of the cylinder head from the engine.
Records indicated that a 50-hour aircraft inspection had been performed just one week prior to the event, during which the spark plugs had been removed. During the post-accident examination, the specific spark plug associated with the crack was found to be loose within its threads.