The last moments of a pilot whose plane crashed while he put on an unauthorised aerobatics display for a friend's retirement party are described in an official report into the tragedy.

The last moments of a pilot whose plane crashed while he put on an unauthorised aerobatics display for a friend's retirement party are described in an official report into the tragedy.

As he spiralled to the ground from 5,000ft, 40-year-old Steve Cowham, of Wingfield, near Eye, realised he was out of control and put out a final radio mayday call telling air traffic controllers he was about to crash.

His final words over the radio are contained in an Air Accident Investigation Branch report just released about the accident on July 16 last year at nearby Hoxne.

According to the report, Mr Cowham radioed that he was "in a spiral spin", adding: "Cannot recover."

The report said that moments later Mr Cowham - whose wife, children, parents and friends were watching - died instantly as the 1993 Slingsby Firefly hit the ground and burst into flames.

The accident investigators failed to pinpoint a specific cause for the crash. Their report said a post-mortem examination did not suggest Mr Cowham was suffering from any medical problems at the time of the crash, and there were no indications of mechanical problems with the plane.

However, the report said the accident occurred at a time when Mr Cowham was part way through an aerobatic course and that it happened on what seemed to be his first attempt to fly aerobatics on a solo flight - even though this had not been authorised by his instructor.

Mr Cowham, who obtained his private pilot's licence in November 2005 and had 83 hours of flying experience, had told a few close relatives and friends he was planning to perform an aerobatic sequence at the retirement party, for friend and neighbour Alan Smith.

At the time of the accident, he had completed 18 flights in the Firefly, nine of which had included aerobatic manoeuvres. Comments on his progress sheet indicated that his proficiency at general handling and aerobatics was "inconsistent".

The plane had taken off from Old Buckenham Airfield, and was seen shortly after 1.50pm, by partygoers and others in the area, performing a rolling manoeuvre and then entering a loop.

The report said that during the unexpected spin, Mr Cowham would have been disorientated and confused, but had sufficient awareness to transmit the radio call. It also said that, even though a parachute was available, he was not wearing one at the time of the crash and, therefore, had no opportunity to abandon the plane.

The report recommended that pilots undertaking aerobatic training should be advised not to fly solo until they have been trained, and proved competent, in recovering from spins.