A coroner heard today (Tuesday, April 30) of the horrific deaths of an elderly pilot from Newbury and three other men who perished when a helicopter and a light plane collided at 1,000ft in mid-air over historic Waddesdon Manor, Buckinghamshire.

Michael Green, 74, was teaching flying training to 32-year-old Thanh Nguyen in the helicopter when the tail of the Cessna 152 plane was clipped by the Cabri G2 helicopter at a height of about 1,000ft.

Savaan Mundae, 18 and Jaspal Bahra, 27, were in the light aircraft.

It was previously thought the crash was caused when the Cessna suddenly dropped in height and hit the tail of the helicopter over the Waddesdon Estate.

The inquest in Buckinghamshire heard that both had taken off from Wycombe Air Park, also known as Booker Airfield, about 20 miles away from the crash site on November 17, 2017.

The incident triggered an investigation by the The Air Accidents Investigation Branch (AAIB), assisted by Thames Valley Police.

An AAIB report published almost one year after the crash concluded: "The opportunity for the occupants of either aircraft to see the other was limited because, although they were in proximity for some time, they were both following a similar track and were not in each other's field of view."

Coroner Crispin Butler told the hearing the helicopter, carrying Mr Green and Mr Nguyen, took off at 11.45am.

It was followed one minute later by the light aircraft in which Mr Mundae and Mr Bahra were flying, before both aircraft collided at approximately 12.00pm.

Giving evidence to the coroner, Home Office forensic pathologist Alexander Kolar told the hearing that all four of the deceased had suffered multiple severe injuries in the crash and offered causes of death of multiple injuries for each.

He said to the inquest jury: "My role is the investigation of sudden deaths and interpreting injuries - my role is in conducting examinations and giving evidence in court."

He offered causes of death of multiple injuries for each victim in the collision and explained the “unsurvivable” wounds were severe to the point of extreme.

The jury heard how one witness to the incident, Rupert Hill, had been out pigeon shooting at the time of the collision and described the horrific moment he watched the shower of debris plummeting down from the sky.

"My attention was drawn to something in the sky but I could see lots of debris falling to the floor and the sound of an engine revving to the max.

"I would say I was looking at this from one to one-and-a half miles away.

"I decided it was not a helicopter, but the main body of the plane - along with all of this, I saw another aircraft, a helicopter.

"All of this lasted around 20 to 30 seconds, and I heard the powerful engine noise stop.

"While heading towards the crash scene I got a call from a friend - I told him what I had seen and he told me to call the emergency services."

A Notice to Airmen had been previously issued to warn pilots that airfield air traffic control services would be closed during three 30-minute periods on selected days.

This timeframe lasted from a period between between November 7 to 30 as a result of a staff shortage - and the crash occurred around half an hour after the latest closure was due to end.