The 500 pound World War Two device was picked up during dredging work.
Hampshire Crash Pilot 'Worried About Weather'
A London-based German banker was worried about the weather before taking off in a one-engined aircraft that crashed into the English Channel, an air accident report has said.
Small sections of the Cirrus SR22 flown by Sascha Schornstein, 36, recovered from the sea indicated that the aircraft "experienced a high-energy impact with the surface", said the Air Accidents Investigation Branch (AAIB) report.
The report did not determine the cause of the accident around noon on July 21 last year but said that "pilot incapacitation could not be discounted as a factor".
The AAIB also said the aircraft was being flown in conditions of low cloud or sea fog with little or no discernable horizon.
In addition, Mr Schornstein was qualified to fly only under visual flight rules (VFR) in which a pilot flies only if visibility is good.
The report said that immediately before the crash he was "flying in meteorological conditions that were not suitable for flight under VFR" with the pilot not qualified to fly on instruments.
The report said that before taking off for Le Touquet in France from Blackbushe airport in Hampshire, Mr Schornstein "was concerned about the weather" and flew several circuits of the airfield before departing.
The AAIB said: "The lack of evidence that the pilot used the emergency parachute system and absence of any emergency radio transmission means that pilot incapacitation could not be discounted as a factor."
The report said that, three weeks after the incident, a diver reported aircraft wreckage about nine miles from where the original floating wreckage was found.
Inquiries by the AAIB confirmed this was likely to be from the aircraft but the hazards of recovering it were "excessive for the limited new evidence it might provide".
After the incident, a search failed to find the the missing pilot and was eventually called off, with Hampshire police initially saying it was treating the case as a missing person inquiry.
The pilot's wife, Russian-born Yulia Schornstein, said shortly after the crash that flying had been her husband's passion and he had always been "well prepared" when flying.
640 men were killed when the South African troop carrier was hit by a cargo ship in 1917.
The 79-year-old man suffered a serious head injury in the Cranmer Road car park in Winton.
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