Incident Overview
On September 15, 2013, around 14:30 local time, a private Piper PA-32R with registration F-GGBD was involved in an incident at Lille-Lesquin airport. The aircraft was operated by its owner-pilot for personal convenience. During the event, the engine sustained damage, but no injuries were reported to the pilot on board.
Flight Progression
The pilot had completed a thirty-minute local flight and initiated two traffic pattern circuits on runway 20. While in the early downwind phase of the second circuit, the pilot observed significant vibrations originating from the engine. This was immediately followed by oil spraying onto the cowling and the presence of smoke. Recognizing the severity of the situation, the pilot declared an emergency and executed a landing on runway 08.
Technical Findings
Post-incident inspection revealed a perforation in the upper crankcase near cylinder number 6. The investigation determined that the engine damage resulted from the failure of connecting rod number 6, which was fractured in multiple locations. The manufacturer attributed this mechanical failure to a lubrication defect. Additionally, an oil puddle was found at the pre-flight start-up location, and the oil filler cap was observed to be present but not locked.
Conclusion
The investigation concluded that the connecting rod rupture was likely caused by insufficient lubrication. It is probable that an improperly secured oil filler cap led to a leak, which subsequently resulted in the lubrication failure.