German U-Boat

Growing more desperate by the minute, Prien decides to alter course and sailed north to probe the northeast corner. As he grew closer, finally the silhouette of a large ship loomed in the horizon. Prien grabbed his night binoculars, berthed unusually close to the north shore, he could make out the unmistakable structure of a British battleship, the Royal Oak. About a mile behind her, lay another ship. Partially obscured by the hull, only the bow was visible. With nothing else to identify her with, Prien took her for the Repulse. Actually it was the old 6,900 ton Pegasus seaplane carrier, scheduled for a refit with experimental aircraft catapults intended for convoy duty.

By 12.55am, U-47 had closed in to a position 3,500 yards from the battleship. Still on the surface, all four bow tubes were made ready. Endrass did all the surface targeting. Since the Royal Oak was a certain kill, two torpedoes were aimed at the Repulse. Open tube doors…. Launch torpedoes….. Torpedoes one, two and three away….. The torpedo in tube four intended for Repulse jammed and did not leave its tube.

HMS Royal Oak, a dreadnought battleship of the Royal Sovereign class was a veteran of World War One.

After a run of three and a half minutes, one small explosion was heard. The other two had either missed or misfired – a common flaw with early electric torpedoes. The hit blew a hole in the starboard side of the bow, near the anchor chains of Royal Oak. Nearly all of the 1,200 crew were asleep. Having aroused from their bunks, the men saw water gushing over like a fountain onto the forward upper deck. But Captain William Benn was told the most likely cause was an internal explosion. It was rumored that a refrigerator had blown up. Others thought it was a high flying German bomber that had dropped a bomb somewhere near the bow. No one considered a U-boat attack. In fact, the last thing on their minds was a German U-boat in Scapa Flow. No special precautions seemed necessary and none was taken. Then men soon went back to their bunks.

In the darkness, U-47 was preparing to strike again. Prien thought that one torpedo had struck the Repulse and the other two had missed the Royal Oak. He did not believe a miss was possible at point blank range, and attributed it to faulty torpedoes. While tubes one to three were being loaded and the jammed tube four was being serviced, Prien swung the U-boat around and fired his stern torpedo at the Royal Oak. It too missed. Unbelievable! Any commander would have cursed his luck and relented that the stars were against him. But not Prien. He was determined to finish the job.

At 1.25am, tubes one and two had been loaded. The jammed tube four was now serviced and ready to go. Edging into a closer position, he fired all three torpedoes at the Royal Oak – which he mistakenly identified as unharmed. All three found its target within ten seconds of each other, blowing three holes amidships on her starboard side. The blasts set off a series of raging fires which ignited the cordite magazine, causing it to go off with a fiery orange blast right up through the decks.

The path of attack and escape taken by U-47 in the daring attack of Scapa Flow.

As was recalled by a survivor, “The chap standing alongside me, all he had on was a singlet and a pair of pants and when this flame struck, he went up like a match. Fortunately, I had my wooly trousers on and my service jersey, and it saved my body. I was burnt on the hands, the face, the back of the neck and all my hair had gone”.

Taking water through the holes, the Royal Oak almost immediately listed 45 degrees to starboard. Her great 15 inch guns squirmed in the weight, her 15 inch shells each weighed a ton and a half – came off their racks in the magazine room and were going boom, boom, boom. Water gushed in below decks, uncontrollable raging fires on the upper decks, and chaos throughout while survivors clambered to get out through the port side. Thirteen minutes later, she rolled over and sank, taking with her 833 sailors and officers of her 1,200-man crew – among them Rear Admiral Henry Evelyn Blagrove, the commander of the 2nd Battle Squadron.

Across the Flow, the sleepy moonless night had awaken to a euphoria of activity. A few vessels began rescue operations, searchlights were all switched on and pointed upwards, all eyes were on the skies, searching and looking for the elusive aircraft that had caused much devastation. No one was looking for a U-boat.

Over a mile away, Prien spied at the hellish scene from the conning tower of his boat. “He’s finished”, he said. Its time to make a getaway.

Next: Retreat From Scapa Flow