Four killed after plane and helicopter collide in mid-air
Police are resuming their hunt for clues this morning following a mid-air collision between a helicopter and an aircraft which killed two pilots and two passengers.
Investigations at the scene near Waddesdon in Buckinghamshire are expected to continue through the weekend and into Monday morning.
Superintendent Rebecca Mears of Thames Valley Police said: "We did a joint response with the fire service, ambulance and now the Air Accident Branch is working with us for a joint investigation while we establish the cause of the crash."
She added that informing the next of kin and supporting them with specialist officers is a priority.
The crash happened in Upper Winchendon, close to Waddesdon Manor, on Friday, though a spokeswoman for the estate said it had not happened on its grounds.
Both aircraft came from Wycombe Air Park, also known as Booker Airfield, near High Wycombe, which offers flight training.
The plane that crashed was a Cessna 152, which has the capacity for one pilot and one passenger.
It was built in 1982 and is owned by Airways Aero Associations, which is based at the airfield.
It had been flown for almost 14,000 hours as of May.
RAF Halton, 10 miles away, said no military aircraft had been involved.
The AAIB sent a team to investigate the crash, and a Thames Valley Air Ambulance also went to the scene.
A spokesman for Waddesdon Manor told Sky News the crash had happened near Upper Winchendon and staff from the estate had gone to the scene in order to help direct traffic.
No one on the estate was harmed and the Manor will be open as usual on Saturday.
A Notice to Airmen (NOTAM) was previously issued to warn pilots the airfield's air traffic control services would be closed during three 30-minute periods on selected days in November due to a "staff shortage".
There were closures scheduled for 17 November between 11am-11.30am, 1.30pm-2pm and 4pm-4.30pm.
Emergency services were alerted to the accident at 12.06pm - around half an hour after the first closure was due to end.
A woman who was walking her dogs at the time of the collision said she heard a helicopter circling overhead "and then heard sirens" and smelled smoke.
Waddesdon Estate Gardener, Len Bellis, had been working nearby when he heard a "horrendous noise" before finding the "burning wreckage".
Mr Bellis said the aircraft was a "wreck" and "non-existent", apart from the burning fuselage.
A police cordon is in place outside the entrance to the Waddesdon estate.
