A BBC TV programme will show the full story one of Wirral's worst maritime disasters - the sinking of the submarine Thetis in a special programme tomorrow night (Thursday).

Sixty years ago this week, on October 23 1939, Thetis was salvaged from Liverpool Bay where she had sunk with the loss of 99 lives.

Pictured above is an exclusive preview of the BBC's sophisticated computer graphics which show the boat sinking in Liverpool Bay.

The submarine had been launched at Cammell Laird in the summer of 1938 and, by the time she went on her sea trials, the second World War was just three months away.

To the Navy, Thetis was an important weapon, and the programme shows how Winston Churchill became involved in the question of who was responsible for the sinking. As First Sea Lord, and head of the Admiralty, Churchill suppressed an official report which would have blamed the navy for the deaths.

Death in the Bay, part of the Close Up North series of BBC2, investigates the cause of the accident and reveals new evidence about who was to blame.

The documentary shows how the submarine crew, and fitters from Cammell Laird, had been trapped inside the boat for 25 hours.

Inside the submarine - as the carbon dioxide replaced oxygen it took one exhausted man more than 15 minutes to climb the steep angle to the control room.

By the afternoon of June 2 four men had escaped from the Thetis using breathing apparatus. One of the survivors was a naval rating - Stoker Walter Arnold. Sixty years on his son Derek, from Bebington, recalls his father's description of the conditions on board as time ran out: "They were sleepy basically, they just didn't have any energy, they couldn't think straight. They were just sitting there, they weren't making any effort, they were just going down and down and down."

The day after the submarine had sunk, the Navy tried to keep her stern above the waterline by using wire hawsers attached to ships. The plan failed and Wirral was left to mourn scores of its young men.

George Luck, from Moreton, was in Portsmouth when he was given news of the disaster and told his four brothers may be dead.

Said Mr Luck: "I was given four days leave and a railway ticket, because I think I had about two and ninepence on me at the time. I arrived home, as far as I can recall, about an hour after my mother received a telegram saying give up hope."

The programme, made with the help of Wirral author David Roberts, will be shown at 7.30pm on Thursday.

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