The 500 pound World War Two device was picked up during dredging work.
Red Arrows Perform Again
Eight Red Arrows pilots took to the skies at air shows in Derbyshire and North Yorkshire on Friday 2nd September, in their first public performances since the death of one of their team-mates in Bournemouth.
The aerobatics display team adapted their formations after the loss of Flight Lieutenant Jon Egging, 33, who died when his aircraft came down near Bournemouth Airport in Dorset on August 20 after performing at an air show.
At Chatsworth Country Fair in Derbyshire the remaining pilots wowed crowds with dazzling formations, which were all the more poignant without Flt Lt Egging, Squadron Leader Graeme Bagnall, better known as Red 10, said before the show.
''It's been a sad two weeks of course and without him in the formation there will be something missing,'' he said.
''However, this is our chance to honour him and pay our respects to him with our flying.
''We think he would have liked us to have gone on to do that, that's why it's so important for us to keep going.''
Sqn Ldr Bagnall, who talked crowds through the display from his position on the ground in the grand arena at Chatsworth House, asked for a moment's silence as the Red Arrows carried out their diamond formation, which would usually be a perfect diamond with Flt Lt Egging as the ninth plane.
He said the piece was dedicated to their fallen comrade and said he could still see him flying in his usual position.
Crowds applauded furiously as the team carried out the Cupid formation - where the planes form a heart shape in smoke trail and another flies an arrow through it - which Sqn Ldr Bagnall dedicated to Flt Lt Egging's widow, Emma.
Earlier in the day the Red Arrows also displayed at the RAF Linton-on-Ouse Families Day in North Yorkshire.
However they cancelled more appearances due to take place on Saturday September 3rd and Sunday 4th, to attend Jon's funeral.
It's thought it took place in the village of Morcott where his widow, Dr Emma Egging, lives.
More than 6000 people have now signed a book of condolence for the Red Arrow pilot and Bournemouth councillors are looking into setting up a memorial in the town.
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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