Planes in near-miss over Duxford during aerobatics practice

A T6 Harvard, similar to the one pictured, was on a "transit" flight at the time of the near-miss

Two planes had a near-miss while a pilot practised aerobatic manoeuvres, an investigation found.

The yellow T6 Harvard was on a "transit" flight when it came into proximity with another aircraft over Duxford, near Cambridge, on 7 May.

A UK Airprox Board report said the other plane was doing a vertical manoeuvre, but the Harvard pilot had effectively not seen it.

The board considered the risk of collision as A, the highest category.

According to the report, the Harvard pilot only saw the other plane, an Extra EA300L, as it "passed through their level in their 7 o'clock".

It said it meant it was an "effective non-sighting" and was too late to have "materially affected the separation".

'Very little separation'

Duxford is a former RAF base that operates as a civilian airfield and is also home to the Imperial War Museum.

The board said the Extra pilot had stopped manoeuvring after seeing a Spitfire in the area to keep "traffic in sight and ensure it had left the area in which they had been practising".

Spitfires are a regular sight at Duxford, which is home to the Imperial War Museum's aviation collection

It said the Extra pilot had spotted the Harvard as they recommenced their aerobatic manoeuvres, but they had sighted it late and then had "not allowed sufficient separation from the Harvard during their vertical manoeuvre".

"It was clear to the board from the NATS (National Air Traffic Services) radar replay that there had been very little horizontal separation," the board said.

"Therefore, members agreed that separation had been reduced to the bare minimum and there had been a serious risk of collision between the two aircraft."