With the waves lapping gently underneath them, and their heads solemnly bowed, three survivors who had been on board HMS Royal Oak when it was sunk by the Germans off Orkney 70 years ago, yesterday visited the scene to pay tribute to those they lost.

Kenneth Toop, 86, from Basingstoke, Bert Pocock, 87, from Reading, and Norman Thackery, 89, from Stokesay Castle, Shropshire, joined the Princess Royal for a special memorial service on HMS Penzance, close to the wreck at Scapa Flow. They are among just a handful of men who can bear witness to what happened aboard the vessel, which sank within 13 minutes of being struck by torpedoes on October 14, 1939.

A German submarine attacked the battleship in the dead of the night, while most of its 1,200-strong crew were asleep below deck. More than 800 men lost their lives in the tragedy, with those who escaped suffering terrible burns.

Mr Pocock survived because he was sleeping next to a ladder that led to an escape hatch and managed to scramble his way to safety in the dark. He recalls the disaster as if it happened yesterday.

“I had to come back,” he said. “I never stop thinking about all the boys still down there on the mess deck where I’d been sleeping.

“There were four of us from Reading — one lived down the road from me. They went down with the ship and that’s always on your mind.

“Every so often you think of those poor three fellows down there. I wonder what happened to them when the water poured in as the ship capsized.

“They’d have struggled against each other to get out of the hatch, but in the pitch dark they wouldn’t have known where to go.”

HMS Royal Oak was built in the naval dockyards at Devonport, Plymouth, during the First World War. Boasting the largest guns ever fitted on a Royal Navy vessel at that time, it was considered virtually unsinkable until the night Gunther Prien, commander of the German submarine U-47, breached the defences of Scapa Flow.

Just before 1am Prien fired his first salvo of torpedoes. Caught unaware, the men thought the problem was on board and no alarms were raised. Twenty minutes later, a second torpedo wave struck, and the heavily armed, fully fuelled ship capsized within minutes.

“There was a terrific explosion,” Mr Pocock added. “The lights went out and it was a blackout like I’d never seen before.

“I called out a couple of times to see if there was anybody else there, but there wasn’t a soul about. I said: ‘Mum, please help me out of this one’.”

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