A pilot who parachuted from his crashing aircraft into icy waters might have survived if he had worn a life-jacket, an accident report said today.

Father-of-two Nigel Paterson died after the Christmas Eve crash of his former RAF Jet Provost trainer aircraft off the Essex coast.

His aircraft had started spiralling towards the sea after going out of control as Mr Paterson, 40, from north London, carried out low-level aerobatics.

The only person aboard, Mr Paterson was seen parachuting from the jet off the coast at Bradwell-on-Sea, near Burnham-on-Crouch.

The sea temperature was measured at five degrees C, said the report into the incident by the Air Accidents Investigation Branch.

It was not until Christmas morning last year - nearly 20 hours after the crash - that Mr Paterson's body was recovered some way north of the crash scene.

The report said: The transition from a warm cockpit to near-freezing temperatures would have been in the order of a few seconds."

It caused a tremendous thermal shock to the pilot's body, it added. Mr Paterson probably lost consciousness shortly after hitting the water, but did have time to release himself from his parachute harness and remove his helmet, said the report.

"Had he been wearing a life-jacket and been able to inflate it, he would, although lapsing rapidly into unconsciousness and suffering from hypothermia, most probably have survived with his head supported clear of the water, for the 20 minutes or so that it took for airborne rescue services to arrive on the scene."

Radar evidence and witness statements suggest that Mr Paterson, who had taken off at 1.14pm from North Weald, was carrying out aerobatic manoeuvres in an area adjacent to the coast at a height of about 3,500ft, said the report.

It added the chief pilot of the independent organisation to which Mr Paterson belonged subsequently issued a flight safety notice banning non-authorised solo aerobatics at under 5,000ft.

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