Background
Loganair Flight LC 621 was scheduled to fly from Kirkwall on Orkney Island to the islands of Stronsay and Sanday. The departure was delayed due to mist and low cloud at Kirkwall. Weather information for Stronsay and Sanday came from informal reports by airfield attendants, as no formal weather reporting facilities exist there.
Flight to Stronsay
At 07:50, the commander deemed conditions at Kirkwall suitable for VFR takeoff. The BN-2 Islander departed with six passengers, landing uneventfully at Stronsay at 07:58. Two passengers disembarked and three joined for the 6-mile flight to Sanday, which departed at 08:03.
Approach to Sanday
Approaching Sanday from the southwest, visibility was 2 miles with very low patchy stratus and a higher cloud layer. The pilot flew at 300 feet amsl at 90 knots. Recognizing the chequerboard markers near the grass runway 03 and the windsock indicating wind 140°/15-20 knots, the commander descended to 250 feet amsl for a downwind approach to runway 11. He then lost sight of the airfield in deteriorating visibility and climbed to 600 feet amsl above the cloud layer.
Descent and Attempted Landing
While tracking to Kirkwall, the commander saw cloud-free areas about 3 miles off the northwest coast of Sanday. He descended over the sea to 300 feet and approached the coast at 90 knots, intending to map-read back to the aerodrome. He saw Whale Point 2-3 miles distant and planned to follow a road southwest, then turn southeast to final approach. After failing to recognize the turning point, he circumnavigated the aerodrome to intercept the road. Aware of carburettor icing risk, he applied carburettor heat just before final approach. He lined up using a school as reference and identified the runway markers of runway 11. The aircraft's speed had reduced from 65 knots, though the actual speed was unknown. The left wing dropped, and a sink rate developed. The stall warning system activated, and full throttle could not prevent ground contact. During the final descent, the aircraft turned 55° left and struck the ground 450 feet short of the runway threshold.
Aftermath
The commander initially thought the aircraft had bounced and attempted to climb. With full throttle applied, the aircraft crossed two barbed wire fences, a small quarry, and a shallow ditch before coming to rest after a fourth fence, 1,065 feet from the initial impact point. The commander closed the throttles and shut down the engines.
Probable Cause
The official finding stated that the accident was caused by the commander's decision to continue a low level VFR flight in meteorological conditions which were inappropriate. His low experience of the task was a contributory factor.