What happened
On 4 May 2019, a pilot was conducting a private cross-country flight in a Rolladen-Schneider LS7, registration G-CFMY, traveling from Talgarth Airfield towards Snowdonia National Park. The flight began with an aerotow launch at 1013 UTC, reaching an altitude of 2,000 ft amsl. Throughout the morning, the pilot navigated through challenging conditions, including a 20 kt wind and varying cloud bases.
During the flight, the pilot maintained contact with his wife via mobile phone, with the final conversation occurring at 1349 UTC. GPS data from a tablet computer indicates that after soaring near Denbigh, the glider moved towards the southern area of Snowdonia. By approximately 1412 UTC, the aircraft was at 1,630 ft amsl, heading south-west. Shortly thereafter, the glider performed a right-hand orbit and began a descent. The flight path then became erratic, involving a left turn followed by a right turn towards rising terrain, before the aircraft impacted a field near Blaenau Ffestiniog at 1416 UTC. The impact resulted in one fatality.
The investigation
The AAIB investigation examined the wreckage, the aircraft's maintenance records, and meteorological data. The investigation recovered GPS track logs from a memory card within the pilot's tablet, which provided a detailed reconstruction of the flight path. The aircraft was found to be structurally intact prior to the impact, with the landing gear extended and the airbrakes partially deployed.
A post-mortem examination was a critical component of the investigation. The pathologist identified a significant coronary artery blockage, specifically an acute thrombus in the left anterior descending artery. The examination suggested this medical event occurred prior to the impact and was sufficient to cause sudden death or render the pilot unconscious. The investigation also reviewed the pilot's medical declarations and flight experience, noting he was a highly experienced instructor with over 3,300 hours of flight time.
Findings
- The pilot suffered a heart attack during the flight, which likely caused him to become unconscious or led to his death before the aircraft struck the ground.
- While the glider was being actively piloted for much of the flight, the erratic maneuvers and turns towards rising terrain at low altitude suggest the pilot was significantly impaired by the medical event.
- The aircraft's landing gear was in the down position, and the airbrakes were partially extended, suggesting an attempt to land may have been underway.