What happened
On 2 October 2006, two gliders were soaring near Sutton Bank in North Yorkshire at an altitude of approximately 1,500 feet. The first aircraft, a Scheibe SF27 with registration HGM, was flying near the base of a cloud when the pilot suddenly observed the second aircraft, a Schleicher ASW 19B registered as GDP, approaching at very close range. In an attempt to avoid a collision, the pilot of the HGM performed an evasive manoeuvre, but the two aircraft collided in a near head-on impact.
The collision caused severe damage to both gliders. The wing of the HGM separated from its fuselage, and the canopy and frame were heavily damaged. The pilot of the HGM managed to exit the aircraft through a hole in the canopy and successfully deployed a parachute, landing in a nearby wooded area with minor injuries.
In contrast, the GDP sustained catastrophic damage, with one wing separating halfway along its span. The pilot of the GDP sustained fatal impact injuries. The pilot's harness had been unfastened before the impact, and while the canopy had partially released, the parachute was not deployed.
The investigation
The investigation focused on the mechanics of the canopy release and the impact dynamics. Investigators found that a section of the GDP canopy was located 500 m from the wreckage, while the remainder was near the fuselage.
Examination of the GDP revealed that the aircraft had been modified with electronic equipment, including a GPS, a logger, and a palmtop computer. These devices were attached to the glare shield and canopy frame using cables secured with cable ties. The investigation established that these cables were positioned in a way that could have interfered with the canopy jettison mechanism.
Findings
- The collision occurred when the two aircraft flew into each other during a close-range encounter.
- The HGM pilot attempted an evasive manoeuvre but was unable to prevent the impact.
- The installation of electronic equipment and associated wiring on the ASW 19B canopy frame likely interfered with the successful completion of the canopy jettison sequence.
- In the HGM, the pilot initiated the jettison procedure, but the locking pins remained in the locked position prior to impact.
Safety action
- Safety Recommendation 2006-127: The British Gliding Association (BGA) should advise pilots to include a pre-flight check to ensure no modifications prevent the canopy from being jettisoned.
- Safety Recommendation 2006-128: The BGA should remind inspectors to ensure that canopy jettison systems can operate without restriction.