A Coroner’s report was sent to the CAA on 17th May 2019 following the inquest into the mid-air collision between a Cessna 152 and a Guimbal Cabri G2 helicopter near Waddesdon Manor in Buckinghamshire on 17th November 2017.

The full report sent to the CAA can be read here:

Below is an extract from the report regarding electronic conspicuity.


During the course of the inquest the evidence revealed matters giving rise to concern. In my opinion there is a risk that future deaths could occur unless action is taken. In the circumstances it is my statutory duty to report to you.

The MATTERS OF CONCERN are as follows.

(1) It was clear from the evidence of The Air Accidents Investigation Branch (AAIB) and The Civil Aviation Authority (CAA) that aircraft such as the two involved in this collision operate in unregulated Class G airspace such as exists in the area of this collision without the requirement to carry any inter-craft electronic proximity warning or collision avoidance devices and are primarily kept safe by operating under the “See and Avoid” procedure which remains the same today as it was on 17th November 2017 (when the collision occurred). It appears this has also been the case for many years before that. This procedure is entirely reliant upon pilots seeing other craft and undertaking periodic clearing turns to try to bring craft into view which might be concealed by a blind spot particular to that craft. It was the view of the AAIB that the “See and Avoid” procedure was central to the cause of this collision.

Although evidence was given by CAA about movement towards the introduction of electronic devices, it was clear that, without universal application, small craft would remain at risk and that timescales for implementation are unclear, leaving “See and Avoid” as the continuing process by which these types of craft avoid collisions.