Accident Overview
On 15 March 2005 at 0018 UTC, a Pilatus Britten-Norman BN2B-26 Islander, registration G-BOMG, operated by Loganair Limited, crashed into the sea 7.7 nautical miles west-north-west of Campbeltown Airport, Scotland. The aircraft was engaged in an air ambulance task for the Scottish Ambulance Service. The pilot had not flown for 32 days and was required to complete a short currency flight before the mission. Poor weather at Campbeltown necessitated an instrument approach; the airport had no radar or Air Traffic Control, so the pilot received a Flight Information Service.
After arriving overhead Campbeltown, the aircraft flew outbound on the approach procedure for Runway 11 and began a descent. The pilot transmitted that he had completed the ‘base turn’, indicating he was inbound. No further communications were received. An extensive search located the wreckage on the sea bed. There were no survivors.
Investigation Findings
The investigation found that the aircraft was certified, equipped, and maintained in accordance with regulations. The aircraft’s weight and center of gravity were within limits. There was no evidence of pre-impact failure in any system; the aircraft was intact when it struck the sea. The elevator trim setting would have resulted in a hands-off trim speed of 110 to 120 KCAS. Damage was consistent with a controlled flight attitude at typical operating speed with symmetric engine power. No technical fault was identified.
The pilot was correctly licensed and qualified. He met flight and duty time limitations and had undergone training in stress and fatigue. However, he had not flown for 32 days and lacked recent practice. The pilot may have been suffering from fatigue, and workload may have degraded situational awareness. The cloud base in the accident area was probably as low as 200 ft with visibility approximately 2,000 m, providing few environmental cues.
The aircraft descended below the minimum outbound altitude of 1,540 ft at a steady rate of about 1,000 ft/min. At the last recorded radar position, it was 200 ft below the minimum altitude and still descending. The autopilot was probably not in use in the final stages.
Causal Factors
The investigation identified the following causal factors: the pilot allowed the aircraft to descend below the minimum altitude for its position on the approach procedure, and this descent probably continued unchecked until the aircraft flew into the sea. A combination of fatigue, workload, and lack of recent flying practice probably contributed to the pilot’s reduced performance. The pilot may have been subject to an undetermined influence such as disorientation, distraction, or subtle incapacitation.
Safety Recommendations
Three safety recommendations were made:
- Safety Recommendation 2006-101: European Aviation Safety Agency and Joint Aviation Authorities should review the UK CAA’s proposal to mandate shoulder harnesses on all seats of transport category aeroplanes below 5,700 kg.
- Safety Recommendation 2006-102: The CAA and JAA should review circumstances requiring a second pilot for public transport air ambulance flights.
- Safety Recommendation 2006-103: The CAA and JAA should consider mandating a radio altimeter or other low height warning device for single-pilot public transport IFR flights.