What happened
On 15 March 2005, a Pilatus Britten-Norman BN2B-26 Islander, registration G-BOMG, was conducting an air ambulance mission near Campbeltown, Scotland. The flight was operating as a non-scheduled public transport service, carrying a pilot and a paramedic.
During the approach to Campbeltown Airport, the pilot intended to follow a VOR/DME procedure for Runway 11. However, the aircraft descended to 3,000 feet before reaching the 'MAC' VOR/DME, which was below the required minimum altitude. The aircraft continued to descend below the minimum outbound altitude of 1,540 feet at a steady rate of approximately 1,000 feet per minute. At its final recorded radar position, the aircraft was 200 feet below the required altitude and still descending. The aircraft subsequently struck the sea.
The investigation
The AAIB investigation examined the aircraft's maintenance history, the pilot's training and recent flying experience, and the meteorological conditions at the time of the accident. Investigators analyzed radar recordings and wreckage patterns, which indicated the aircraft had descended at a relatively constant rate after disappearing from radar.
The investigation also looked into the survivability of the impact. While the cockpit area remained relatively intact, the paramedic sustained head injuries due to the lack of upper torso restraints on the passenger seat. The investigation also reviewed the pilot's recent flying currency and the impact of fatigue and workload on flight performance.
Findings
- The pilot allowed the aircraft to descend below the minimum altitude for the approach procedure, a descent that likely continued until impact.
- The pilot was likely experiencing a combination of fatigue, high workload, and a lack of recent flying practice, which contributed to degraded performance.
- Environmental factors, including a low cloud base of approximately 200 feet, provided very few visual cues to alert the pilot to the low altitude.
- The absence of a radio altimeter or an electronic low-height warning device meant there was no automated alert for the altitude deviation.
- The presence of a second pilot might have prevented the occurrence.