On Friday 17 November, a Cessna 152 light aircraft collided with a Cabri-G2 helicopter at around 1000 feet above the ground. Each aircraft contained an instructor and student, and it is reported that the Cessna aircraft struck the rear of the helicopter, after which both aircraft plunged into woodland below.

Sadly all four occupants in both aircraft died, including helicopter pilot Captain Mike Green who was a senior instructor with more than 30 years of experience, and a member of the Helicopter Services Team based at Wycombe Air Field.

An investigation is underway by the Air Accidents Investigation Branch to understand the cause of the crash after both the helicopter and Cessna plane took off from Wycombe Air Park (also known as Booker Airfield) and later crashed 20 miles away over Waddesdon Estate.

Ashfords' Head of Aviation and specialist aviation lawyer, Jim Morris, was a pilot in the RAF for 12 years with extensive professional experience in operating aircraft and the techniques necessary to maintain safe separation from other aircraft.

Jim Morris commented on the tragic accident: "The AAIB will need to consider a number of factors, including the weather conditions, radar traces, the horizontal and vertical trajectories of both aircraft, any issues affecting the visibility for each crew, whether either aircraft was receiving any form of service from Air Traffic Control (ATC), whether both aircraft were making and listening to transmissions on the same radio frequency and whether there were any issues with ether aircraft that caused a distraction to the pilots.

"If aircraft are operating under visual flight rules, each crew has to ensure that they see and avoid other aircraft by constantly maintaining an effective lookout. This may seem a straight forward process but in the 3D environment that aircraft operate in, it can be a demanding task. A key issue when aircraft are on a collision course is each aircraft will be stationary in each pilot's field of view, making it more difficult to spot the other aircraft. As such, if there are aggravating issues impacting on an effective lookout (which could include flying towards a low sun, a collision course trajectory that means that the other aircraft is obscured by a canopy frame / solid part of the aircraft, a distraction in the cockpit and high rates of horizontal / vertical closure) this can mean that each pilot may not notice that they are going to collide until the last few seconds or not at all.

"Once there has been a collision, if an aircraft receives serious damage to the flying control surfaces or the damage severely affects the aerodynamics, it would be almost impossible for the pilot to recover control of the aircraft, with the inevitable catastrophic consequences.

"At this early stage there are limited facts available so it is to be hoped that the Air Accident Investigation Branch (AAIB) can quickly determine the full chain of events and publish their findings, so that the families can understand what went wrong and lessons can be learned to improve flight safety.

"Our thoughts are with the families of the victims during this difficult time."