Aircraft Accident Report AAR 5/2010 - Grob G115E (Tutor), G-BYXR and Standard Cirrus Glider, G-CKHT, 14 June 2009

Formal Report AAR 5/2010. Report on the accident between Grob G115E (Tutor), G-BYXR and Standard Cirrus Glider, G-CKHT at Drayton, Oxfordshire on 14 June 2009


A Grob 115E Tutor aircraft, operated by the Royal Air Force (RAF), was undertaking a cadet air experience flight from RAF Benson. The visibility was good and the aircraft was conducting aerobatics, in uncontrolled airspace, when it collided with a glider. The left wing of the Tutor struck the fin of the glider causing the tail section to break away. The glider pilot parachuted to safety. The Tutor entered a spiral / spinning manoeuvre before diving steeply into the ground. The Tutor pilot and cadet were both fatally injured.

The Tutor pilot had a long term medical condition which restricted the movement of his head and affected his ability to conduct an effective look-out; this condition also made him more vulnerable to impact fractures of the spine. Following the collision it is probable that the Tutor remained controllable, suggesting that the pilot had become incapacitated.

The cadet’s harness had been released and the canopy operating handle had been moved to the open position before the Tutor impacted the ground. The canopy jettison mechanism had not been operated.

The accident was notified to the Air Accidents Investigation Branch (AAIB) at 1350 hrs on 14 June 2009 and an AAIB field investigation was commenced immediately. The investigation was conducted by:

Mr P Claiden - Investigator-in-charge Mr A Blackie - Operations Mr B D McDermid - Engineering Mr M Ford - Flight Data Recorders

The investigation identified the following causal and contributory factors:

Causal factor

  1. Neither pilot saw each other in sufficient time to avoid the collision.

Contributory factors

  1. The Tutor pilot’s medical condition, Ankylosing Spondylitis, limited his ability to conduct an effective look-out.

  2. The high density of traffic, in an area of uncontrolled airspace, increased the risk of a collision.

Thirteen Safety Recommendations have been made.

Download full report:

5-2010 G-BYXR and G-CKHT.pdf (2,123.66 kb)

Download bulletin summary:

Summary: AAR 5/2010 Grob G115E (Tutor), G-BYXR and Standard Cirrus Glider, G-CKHT

Published 10 December 2014