History of the Flight
The aircraft, an Ikarus C42 FB80 registered G-SJEN, was operating close to its maximum total weight authorised (MTWA) of 450 kg, with an actual weight of 440 kg. It was returning to Strathaven Airfield after a short local flight. The surface wind was reported as from the east at 4.5 to 9 kt, with towering cumulus and cumulonimbus clouds nearby over a ridge of hills 4 nm to the south. Visibility exceeded 10 km, and the broken cloudbase overhead the airfield was at 3,000 ft agl.
Approach and Go-Around
The pilot planned to land beyond the normal touchdown point on Runway 09. During final approach, he observed from the airfield's windsock that the wind had shifted 180° and now favoured Runway 27. He commenced a go-around, retracting the flaps. During the go-around, lightning was observed over the hills to the south. The intention was to carry out a short circuit to the south, over lower ground, and establish the aircraft on left base for Runway 27 at 500 ft agl.
Accident Sequence
As the aircraft turned to the right over some trees at a height of approximately 300 ft agl, the pilot reported that the controls became ineffective. Witnesses at the airfield saw G-SJEN descend steeply before it disappeared from view behind trees. The pilot had no recollection of events between the controls becoming ineffective and seeing the propeller strike the ground as the aircraft slid to a halt in a field ¼ nm east of the airfield.
Occupant Actions and Aircraft Damage
Both the pilot and passenger, who were wearing four-point harnesses, vacated the aircraft through their respective doors. They were uninjured and were soon joined by staff and members from the airfield. Witness marks in the well-established long grass indicated the aircraft had been in a left-wing-low attitude just before making a heavy three-point landing. During the landing, the nose and left main landing gear collapsed, and the aircraft came to a stop after slewing through about 90° to the left. Damage was sustained to the propeller, nose and both main landing gear, fuselage, engine mounts, and engine cowling.
Meteorological Conditions
Meteorological observations at 1820 hrs at nearby Glasgow and Prestwick Airports recorded surface winds from 240° at 11 kt and from 260° at 8 kt, respectively.
Pilot's Conclusion
The pilot concluded that the aircraft had stalled in the turn. He considered that possible windshear, associated with the nearby cumulonimbus clouds, a downdraught in the lee of the trees over which he flew, and concern about the lightning were contributory factors.