Synopsis
On 17 August 2008 at approximately 1036 UTC, a Cessna 402C registered as G-EYES and a Rand KR-2 registered as G-BOLZ collided in mid-air near Coventry Airport. The accident occurred in Class G (uncontrolled) airspace, about 3.0 nautical miles from the threshold of Runway 23. G-EYES was engaged in flight calibration training and was conducting an Instrument Landing System (ILS) approach to Runway 23. G-BOLZ was operating in the visual circuit. The four occupants of G-EYES and the single occupant of G-BOLZ sustained fatal injuries.
Investigation
The Air Accidents Investigation Branch (AAIB) commenced a field investigation immediately after the accident was notified by Warwickshire Police. The investigation examined the aircraft, their maintenance, pilot qualifications, air traffic control (ATC) procedures, and operational factors.
Findings
Both aircraft were properly maintained and serviceable. The crew of G-EYES and the pilot of G-BOLZ held valid licenses and were qualified for their respective flights. All relevant ATC equipment was serviceable. There was no evidence that the pilots took action to avoid the collision. G-BOLZ was on a constant bearing relative to G-EYES for approximately three minutes before impact. At the collision point, G-BOLZ crossed G-EYES’ track at an angle of 43°, and G-EYES was overtaking G-BOLZ at a relative speed of about 106 knots. The sightline from the front right seat of G-EYES to G-BOLZ probably intersected the canopy behind or slightly left of the windscreen central pillar.
Probable Cause
The two aircraft collided because their respective pilots either did see the other aircraft, or did not see it in time to take effective avoiding action.
Contributory Factors
The investigation identified several contributory factors: the small size of G-BOLZ, its position relative to G-EYES, and the high closure rate reduced the likelihood of the G-EYES crew seeing G-BOLZ in time. Insufficient or inaccurate information was provided to pilots, hindering their ability to avoid collisions. The Aerodrome Controller’s sequencing plan, based on an incomplete understanding of G-EYES’ flight nature, was unlikely to succeed. The ATC flight progress strip incorrectly annotated G-EYES’ activity as 'IRT' (Instrument Rating Training) instead of ILS calibration work. The pilot of G-BOLZ was not informed about G-EYES approaching on the ILS. There were no effective measures to give G-EYES priority over traffic in the visual circuit. The collision occurred outside the Coventry Airport Air Traffic Zone (ATZ) in Class G airspace.
Safety Recommendation
The AAIB issued Safety Recommendation 2010-003 to the Civil Aviation Authority (CAA), recommending that the requirement in Part 1 of the Manual of Air Traffic Services for Aerodrome Control to issue 'information and instructions to aircraft under its control to achieve a safe, orderly and expeditious flow of air traffic and to assist pilots in preventing collisions' be ensured as suitable, sufficient, and complied with.