What happened
On May 4, 2008, a Pilatus PC-6/B2-H4, registration EI-IAN, was performing routine aerial work involving parachute drops at Clonbullogue Airfield in Co. Offaly. Following a successful mission, the aircraft was on short finals for the westerly runway when it began to sink below its intended visual approach profile. In an attempt to recover the descent, the pilot increased engine power; however, the aircraft's underside made contact with a wooden fence post embedded within the boundary hedge. While the impact caused substantial damage to the rear fuselage, the pilot escaped without injury, and no fire occurred.
The investigation
The AAIU conducted a field inspection of the aircraft and the airfield. The investigation confirmed that the aircraft was properly maintained with a valid Certificate of Airleworthiness. Physical examination of EI-IAN revealed buckling in the area under the right tailplane due to the compression caused by the impact. The investigators also examined the airfield layout, noting that a hangar located near the threshold of runway 27 could potentially create turbulence under specific wind conditions. The pilot's credentials were also verified, confirming they were properly licensed for parachute-dropping operations under the prevailing regulatory agreements at the time.
Findings
- The primary cause of the accident was that the application of power was insufficient to arrest the sink rate during the final approach.
- The aircraft's descent rate was not corrected in time to avoid the obstacle in the hedge.
- Prevailing southerly winds, combined with the proximity of the airfield hangar, may have created turbulence that contributed to the unstable approach.