Description

On 14 June 2009, a Grob 115E Tutor being operated by the UK Royal Air Force (RAF) and based at RAF Benson was conducting aerobatics in uncontrolled airspace near Drayton, Oxfordshire in day Visual Meteorological Conditions (VMC) when it collided with a Standard Cirrus Glider on a cross country detail from Lasham. The glider was sufficiently damaged that it could no longer be controlled and the glider pilot parachuted to safety. The Tutor entered a spin or spiral manoeuvre which it exited in a steep dive from which it did not recover prior to a ground impact which killed both occupants.

Investigation

An Investigation into the accident was carried out by the UK AAIB. It was established that the Tutor had been conducting an air experience flight for an Air Cadet and that the single seat glider was flying cross country on a 300 km task that had been suggested by his gliding club. At the time of the accident both aircraft were operating in uncontrolled airspace notified as the Oxford Area of Intense Aerial Activity (AAIA) which was relatively congested, especially with gliders, in the prevailing good weather conditions. Neither aircraft was in receipt of an air traffic service at the time of the collision and both were relying on the ‘see-and-avoid’ principle for collision avoidance. No onboard traffic alerting system fitted to the Tutor and the FLARM collision alerting system fitted to the glider was not designed to detect the transmissions from transponders such as that fitted to the Tutor.