What happened
On 7 September 2024, a private flight involving an Aeroprakt A-22L2, registration EI-HNC, resulted in an aircraft impact at a private grass airstrip in Cloongoonagh, Co. Mayo. The pilot was performing a return flight to the site after completing sightseeing trips from a nearby airfield.
As the aircraft approached the runway threshold at a height of approximately 20 feet, the pilot experienced a sudden drop in altitude. In response, the pilot initiated a go-around maneuver by increasing engine power. During this transition, the aircraft veered sharply to the left, causing the left wing to strike a hedgerow running parallel to the runway. The aircraft then came to rest in an adjacent agricultural field. The pilot, who was the sole occupant, exited the aircraft without injury, though the aircraft suffered substantial damage, including broken propeller blades and significant wing damage.
The investigation
The AAIU examined the aircraft's performance, the meteorological conditions, and the site layout. The investigation reviewed the Pilot Operating Handbook (POH) regarding approach speeds and engine power applications. Investigators also analyzed the aerodynamic effects of the Rotax 912 UL engine, specifically how sudden power increases influence flight stability.
Environmental factors were also scrutinized, including the proximity of the hedgerow to the runway edge and the presence of local terrain features like embankments and trees that could influence wind patterns. The investigation also noted that while the aircraft's airspeed was within safe limits, the narrowness of the runway and the proximity of obstacles played a critical role in the outcome.
Findings
- The pilot's decision to perform a go-around was prompted by a sudden loss of altitude, which may have been caused by local adverse wind effects resulting from nearby trees and terrain.
- Increasing engine power during the maneuver triggered aerodynamic forces, including torque reaction, P-factor, and prop-wash, all of which contributed to a leftward yawing and rolling tendency.
- The narrow 4.3-meter width of the runway, combined with the aircraft's 9.55-meter wingspan, left very little margin for error; the left wingtip had only about 6 meters of clearance from the hedgerow at the threshold.
- The proximity of the hedgerow to the runway centerline significantly increased the likelihood and severity of the impact.
- The aircraft's approach speed was approximately 85 km/h, which was within the safe operating parameters for the aircraft type.