HMS Royal Oak
U 47 – Kapitänleutnant Günther Prien
As war approached Admiral Karl Donitz, in charge of the German U-boat arm, was already considering an attack on Scapa Flow, despite the loss of U-18 and UB-116 in the last war. After war broke out he got aerial reconnaissance photographs from the Luftwaffe and came to the conclusion:
In Holm Sound, there are only two steamers which seem to be sunk across Kirk Sound and another on the north side. To the south of the latter end and up to Lamb Holm there are: a first gap 17 m wide at low tide mark, where the depth reaches 7m; and a second smaller, to the north. On both sides the shore is almost uninhabited. I think it is possible to pass there during the night and on the surface at flood tide. The greatest difficulty remains the navigation.
Donitz offered the job to Gunther Prien, captain of U-47, who ‘possessed all the qualities of leadership and all the necessary nautical knowledge’. Prien took the charts and papers home and studied them before agreeing to go. The night of 13/14 October was chosen because slack water was in the middle of the night – the tides could be up to 12 knots and the maximum speed of a submerged U-boat was 7 knots. U-47 sailed on 8 October and four days later she was submerged off Orkney with her officers taking fixes on the navigational lights and observing shipping movements. Early in the morning of the 13th the crew were crowded into the forward compartment and Prien told them what they were going to do. There was silence, but he observed, ‘Their faces were quite calm and nothing was to be read in them, neither astonishment, nor fear.’ The crew rested until the afternoon and then were given a ‘feast’ of veal cutlets and green cabbage. They surfaced at 7.15 in the evening, German time (one hour ahead of British time), and prepared for action, getting the torpedoes ready for reloading and setting charges so that the boat could be blown up if it fell into enemy hands.
Prien headed into Holm Sound but was shocked that it was ‘disgustingly light’ due to the Aurora Borealis. At one stage he mistook the blockship in Skerry Sound for the one in Kirk Sound and nearly went the wrong way. But the navigator used dead reckoning to correct the course. The submarine turned sharply to starboard and headed north, then turned west into the ill-defended Kirk Sound. Prien was well prepared for the passage and went through with ‘unbelievable speed’, scraping against the cable of one of the blockships as the submarine swung violently to and fro in the currents.
Inside the Flow, Prien headed west to look around for warships. There was nothing south of Cava so he turned north to see what he believed were two capital ships, one of the Royal Oak class and the battlecruiser Repulse. In fact the second ship was the aircraft transport Pegasus, formerly the Ark Royal, an early seaplane carrier of the First World War. Prien fired one torpedo at the supposed Repulse and two at the Royal Oak. Only one struck home.
Around midnight Commander Renshaw, the engineer officer of the Royal Oak, was in his bunk when he was awakened by a violent explosion below him in the after part of the ship:
Turned out and pulled on a few clothes and hurried to the Admiral’s lobby. Saw R. A. 2 [Rear-Admiral H. E. C. Balgrove, Second Battle Squadron]. He said ‘That it came from directly below us. Locate what it is, Engineer Commander.’ I said ‘I agree Sir,’ I then opened up W. T. [watertight] door to Tiller Flat. Ordered Mr Dunstons, Warrant Engineer who had arrived to open sliding door cautiously, fully expecting to find compartment flooded. I descended into Tiller Flat, searched, found all in order and came out of it again shutting sliding and W.T. door.
Renshaw searched other parts of the ship on the captain’s instructions and found nothing. He was beginning to think it was an internal CO2 explosion. But in the meantime U-47 got ready for a second attack:
Torpedo fired from stern; in the bow two tubes are loaded; three torpedoes from the bow. After three tense minutes comes the detonations on the nearer ship. There is a loud explosion, roar, and rumbling. Then come columns of water, followed by columns of fire and splinters fly through the air. The harbour springs to life. Destroyers are lit up, signalling starts on every side, and on land 200 metres away from me the cars roar along the roads. A battleship has been sunk, a second damaged, and three other torpedoes have gone to blazes. All the tubes are empty. I decide to withdraw.
On board the Royal Oak, as Renshaw reported,
. . . A second terrific explosion shook ship which immediately began to list to starboard. At intervals of a few seconds, a 3rd and 4th explosion shook ship and list rapidly increased and lights failed. Heard Captain say he was going up to forecastle and followed him up Forward Hatch with a number of others. Made my way aft along Port side to Quarter Deck with list increasing the whole time. Someone, I think a Warrant Officer said to me ‘What is to be done now’ I said “Nothing can save her now.’ R.A.2 emerged from darkness and said ‘What caused those explosions do you think?’ I said ‘Torpedoes, Sir.’ He said ‘My God’, turned away and walked forward. I did not see him again.
Many seamen slept through the first explosion but could not ignore the others. Leading Seaman Green was on watch on the starboard side of the flag deck when he heard the second explosion and saw a column of water alongside the forecastle, followed by more alongside the bridge. On the marines’ messdeck a big yellow flash came through the starboard door and all the hammocks caught fire. The man in the hammock next to Marine A. R. Jordan jumped out but went straight on down, for there was no deck for him to land on.14 Other survivors had equally horrific experiences as the ship turned over:
As he went, half blown, half running, it was hard to keep upright. With all dark below, the ship had begun to heel slowly and remorselessly over to starboard. It was hard to find the doors, still harder to open them, because they were no longer vertical. Several times, Wilson found himself across the diagonal of a door before he had reached out to open it. The ship was really turning now, and he knew he had a long way to go. His goal was a ladder by the galley, leading to the upper deck. About forty men were struggling round it, milling, shouting, cursing, unable to see what they were doing . . .
Also in the scrum was Batterbury. The second explosion had sent him running from forward to his chums in the mess, which was near the ladder. He had only a hundred yards to go, but some of the watertight doors were closed for damage-control purposes and others were slamming to with the heel of the ship; it was impossible to go in a straight line.
A door slammed behind him, crushing the head of a man who was trying to get through it. Batterbury saw his eyes and tongue sticking out, then came the sound of the third explosion, and the lights failed. He ran on. The anti-flash curtains in the battery aft were aflame and people were pouring up from the stokers’ messdeck below, ‘hollering and howling about men being on fire down there’. This new scrum of men, many of them dazed with horror, scrambled for the ladder. It was, said Batterbury dryly, ‘survival of the fittest’. The fear of being trapped inside the heeling ship was overwhelming. Batterbury himself was frantic to get a foot on the ladder.
Meanwhile U-47 was retreating through Kirk Sound.
It is now low tide, the current is against us. Engines at slow speed and dead slow, I attempt to get away . . . Course 058, slow. I make no progress. At high [speed] I pass the southern blockship with nothing to spare. The helmsman does magnificently. High speed ahead both, finally three-quarters speed and full ahead all out. Free of the blockships – ahead a mole! Hard over and again about, and at 02.15 we are once more outside.
The life-saving arrangements on the Royal Oak were inadequate, as her captain had recognised before the sinking. The boats and rafts were insufficient to accommodate the whole crew and could not be launched quickly in an emergency, while requests for life-jackets for all the men had been lost in the Admiralty machine. The hero of the episode was Richard Gatt, skipper of the drifter Daisy II which was alongside the Royal Oak at the time. He backed his boat away from the sinking ship and then lit a gas lamp to alert the men in the water. About 250 were picked up. Boats from the Pegasus, anchored about half a mile away, were launched as soon as the alarm was raised, and went over to the scene, but the base at Lyness was too far away to send help in time. Most of the survivors were taken on board the Pegasus. In all, 833 officers and men were lost out of a total of 1,400.
A court of inquiry concluded that the Royal Oak had indeed been sunk by torpedoes fired by a submarine and there was no evidence of any other form of attack, though conspiracy theories involving sabotage have always surrounded the sinking. The inquiry noted that any of the seven entrances to the Flow was possible, though Switha Sound and Water Sound were extremely unlikely. For example, a U-boat might have entered by
Passing through the gap in the Flotta end of the Hoxa boom on the surface or trimmed down. This gap is [blank] wide with a least depth of water of 15 ft at High Water and considerably more over the greater part. There was no lookout on shore at the gap. One drifter was patrolling the whole entrance which is 1½ miles wide. Approaching this gap would take the submarine within 5 cables of the battery on Stanger Head.
Another possibility was ‘Passing through the opening of Kirk Sound south of S.S. “Thames” on the surface: this opening is 400 feet wide with a depth of 4 to 4½ fathoms at Low Water. There is another opening about 200 feet wide with a depth of 15 feet or more at High Water.’ It was conjectured that ‘in many respects Kirk Sound would present the least difficulty.’ The inquiry identified nine possible gaps in the defences and much needed to be done if Scapa Flow was ever to be safe again.
When the sirens sounded over the Forth on the afternoon of Monday 16 October, two days after the sinking of the Royal Oak, it was not a false alarm. Nine Junkers 88s of the Luftwaffe were under orders to attack the great battlecruiser HMS Hood, which they knew had travelled up the east coast to the firth. But the Hood had already gone into dock at Rosyth and the raiders were instructed not to attack targets ashore, for fear of civilian casualties. Instead they bombed two cruisers, the Southampton and Edinburgh, and the destroyer Mohawk, killing fifteen men in the Edinburgh. The local squadrons of the Royal Auxiliary Air Force, 602 and 603, were already on patrol and shot down two of the Junkers, after mistakenly firing on an RAF Anson. This was the first raid of the war on British territory, and the two Junkers were the first enemy aircraft to fall on British soil. The following day there were raids on Scapa Flow, though the fleet had moved to Loch Ewe by now. The Iron Duke was damaged by a near miss and beached. She was to remain in this state for the rest of the war, still serving as a depot ship.
The wide estuary of the Forth remained a tempting target for bombers, as it had been for U-boats in the previous war. In November, when the Germans first used their ‘secret weapon’, the magnetic mine, they were dropped by aircraft in the Forth and the Thames and the new cruiser HMS Belfast was blown up on the way out of the Forth on the 21st and spent more than two years under repair. It had been put in place by U-31. On 9 February 1940 the Luftwaffe lost two Heinkel 111s, the first in the sea off Peterhead and the second near North Berwick. On 16 March Scapa Flow was raided by fifteen aircraft and some bombs were dropped on land; Mr James Isbister of Bridge of Waithe ran out of his house to help a neighbour but was killed outright by a bomb – the first civilian casualty of an air raid in Britain in the war. A newspaper report of April 1940 suggested that 13 out of 25 bombing raids on Britain had been aimed at Scotland, and 28 out of 47 reconnaissance flights.
If anyone thought this was the shape of things to come, they were wrong. Eventually London was bombed, but the Forth saw very little of the Luftwaffe after the spring of 1940. It was early in 1940 before the first RAF fighters arrived at Scapa and by March three fighter squadrons were operating from the air stations at Wick and Hatston, and Fleet Air Arm squadrons, albeit with obsolete aircraft, were allocated to the air defence. Subsequent German raids on Orkney suffered quite heavy losses. The attack on the Flow intensified in April because the Germans, preparing for a campaign in Norway, had particular reasons to neutralise the Home Fleet. On 8 April a force of sixty bombers arrived, but were driven off by more than 1,700 rounds fired by anti-aircraft guns, while three bombers were shot down by fighters. They attacked again on the 10th and six German aircraft were lost, including one which crashed on landing at its base. There was a half-hearted raid on the 25th but the attack was not pressed home and the only casualty was one chicken. Scapa was no longer an easy target for the Luftwaffe, and by now their attention was diverted fully to Norway.