HMS Royal Oak (08)

Career
Laid down:	15 January 1914
Launched:	17 November 1914
Commissioned:	1 May 1916
Nickname:	The Mighty Oak
Fate:	Sunk on 14 October 1939
General characteristics
Displacement:	29,150 tons standard 33,500 tons full load
Length:	620½ ft (189 m)
Beam:	88½ ft (27 m) as built 102 ft (31.1 m) after bulging
Draught:	28½ ft (8.7 m)
Propulsion:	4 shaft Parsons geared turbines 18 Yarrow boilers 40,000 shp (30 MW)
Speed:	20 knots (37 km/h)
Range:	4,000 nautical miles (7,400 km)
Complement:	1,009 to 1,146 (peacetime)
Armament:	4 × twin Mk I 15-inch/42 guns 12 × single Mk XII 6-inch (150 mm) guns 4 × 2 4-inch (102 mm) guns 2 × 8 2-pdr (900 g) anti-aircraft guns 4 × 21 inch (533 mm) torpedo tubes
Armour:	13 inch belt 6 inch upper belt 10 inch barbettes 13 inch turret faces 4¼ inch turret crowns

His Majesty's Ship Royal Oak (pennant number 08) was a Revenge-class battleship of the British Royal Navy, torpedoed at anchor by the German submarine U-47 on 14 October 1939. Launched in 1914 and completed in 1916, Royal Oak first saw action at the Battle of Jutland. In peacetime, she served in the Atlantic, Home and Mediterranean fleets, coming under accidental attack on more than one occasion. The ship became the centre of worldwide attention in 1928 when her senior officers were controversially court-martialled. During a twenty-five year career, attempts to modernise Royal Oak could not address her fundamental lack of speed, and by the start of the Second World War, she was no longer suited to front-line duty.

Royal Oak was anchored at Scapa Flow in Orkney, Scotland when she became the first of the five Royal Navy battleships and battlecruisers sunk in the Second World War. The loss of life was heavy: of Royal Oak's complement of 1,234 men, 833 were killed that night or died later of their wounds. The numerical superiority enjoyed by the British navy and its allies meant that the loss of the obsolete veteran of the First World War made little difference to the naval balance of power, but the effect on wartime morale was considerable. The raid made an immediate celebrity and war hero out of the U-boat commander, Günther Prien, and on his return to Germany he became the first Kriegsmarine officer to be awarded the Knight's Cross of the Iron Cross. To the British, the raid demonstrated that the Germans were capable of bringing the naval war to their home waters, and the shock resulted in rapidly-arranged changes to dockland security.

Now lying upside-down in 30 m of water with her hull 5 m beneath the surface, Royal Oak is a designated war grave. In an annual ceremony to mark the loss of the ship, Royal Navy divers place a White Ensign underwater at her stern. Unauthorised divers are prohibited from approaching the wreck at any time.

Construction

The Revenge class to which Royal Oak belonged was ordered in the 1913–14 Estimates to be a cheaper—but smaller and slower—coal-fired version of the earlier Queen Elizabeth-class super-dreadnoughts.^[1] The design, seemingly a technological step backwards, was partly a response to fears that a dependence upon fuel oil—all of which had to be imported—could leave the class crippled in the event of a successful maritime blockade.^[2] High-quality coal, on the other hand, was in plentiful supply, and homeland supplies could be guaranteed.^[2] Furthermore, in contrast to the "Fast Squadron" Queen Elizabeths, the Revenge class were intended to be the heaviest-gunned vessels in the line of battle proper.^[3] Royal Oak and her sisters were the first major vessels for the Royal Navy whose design was supervised by the newly-appointed Director of Naval Construction, Sir Eustace Tennyson-D'Eyncourt.

Royal Oak in line astern

Royal Oak was laid down at Devonport Dockyard on 15 January 1914, the fourth of her class.^[a] Concerned over the performance limitations of coal, and having secured new oil supplies with a contract agreed with the Anglo-Persian Oil Company, First Sea Lord Jackie Fisher rescinded the decision on coal in October 1914.^[2] While under construction, Royal Oak was redesigned to employ eighteen oil-fired Yarrow boilers supplying four Parsons steam turbines each driving a single screw. The battleship was launched on 17 November of that year, and after fitting-out, was commissioned on 1 May 1916 at a final cost of £2,468,269.^[4] Named after the oak tree in which Charles II hid following his defeat at the 1651 Battle of Worcester, she was the eighth Royal Navy vessel to bear the name, replacing a pre-dreadnought scrapped in 1914. While building she was temporarily assigned the pendant number 67.^[5]

Royal Oak was refitted between 1922 and 1924, when her anti-aircraft defences were upgraded by replacing the original 3-inch (76 mm) AA guns with 4-inch (100 mm) high-angle mounts.^[6] Fire-control systems and rangefinders for main and secondary batteries were modernised, and underwater protection improved by 'bulging' the ship.^[6][7] The watertight chambers, attached to either side of the hull, were designed to reduce the effect of torpedo blasts and improve stability, but at the same time widened the ship's beam by over 4 meters.^[8]

A brief refit in the spring of 1927 saw the addition of two more 4-inch (100 mm) high-angle AA guns and the removal of the two 6-inch (150 mm) guns from the shelter deck.^[6] The ship received a final refit between 1934 and 1936, when her deck armour was increased to 5 inches (12.7 cm) over the magazines and to 3.5 inches (8.9 cm) over the engine rooms. In addition to a general modernisation of the ship's systems, a catapult for a spotter float plane was installed above X–turret, and anti-aircraft defences were strengthened by doubling up each of the 4-inch (100 mm) AA guns and adding a pair of octuple Mark VIII pompom guns to sponsons abreast the funnel.^[6][8] The mainmast was reconstructed as a tripod to support the weight of a radio-direction finding office and a second High-angle Control Station.^[6] The extra armour and equipment made Royal Oak one of the best equipped of the Revenge class, but the additional weight caused her to sit lower in the water, lowering her top speed by several knots.^[6]

Career

First World War

Royal Oak at Jutland, by William L. Wyllie, R.A.

The First World War had been under way for almost two years when Royal Oak was commissioned. She was assigned to the Third Division of the Fourth Battle Squadron of the British Grand Fleet, and within the month was ordered, along with most of the fleet, to engage the German High Seas Fleet in the Battle of Jutland. Under the command of Captain Crawford Maclachlan,^[9] Royal Oak left Scapa Flow on the evening of 30 May in the company of the battleships Superb, Canada and Admiral Jellicoe's flagship Iron Duke.^[10][11] The next day's indecisive battle saw Royal Oak fire a total of thirty-eight 15-inch and eighty-four 6-inch (150 mm) shells,^[12] claiming three hits on the battlecruiser Derfflinger, putting one of its turrets out of action, and a hit on the cruiser Wiesbaden. She avoided damage herself, despite being straddled by shellfire on one occasion.^[13]

Following the battle, Royal Oak was reassigned to the First Battle Squadron. On 5 November 1918—the final week of the First World War—she was anchored off Burntisland in the Firth of Forth accompanied by the aircraft carrier Campania (formerly a Blue Riband winner for the Cunard Line prior to its conversion for wartime use) and battlecruiser Glorious. A sudden Force 10 squall caused Campania to drag her anchor, collide with Royal Oak and then with the 22,000-ton Glorious. Both Royal Oak and Glorious suffered only minor damage; Campania, however, was holed by her initial collision with Royal Oak. The ship's engine rooms flooded, and she settled by the stern and sank five hours later, though without loss of life.^[14]

At the end of the First World War Royal Oak escorted several vessels of the surrendering German High Seas Fleet from the Firth of Forth to their internment in Scapa Flow,^[15] and was present at a ceremony in Pentland Firth to greet other ships as they followed.

Between the wars

Capt. Kenneth Dewar, court-martialled in 1928

The peacetime reorganisation of the Royal Navy assigned the Royal Oak to the Second Battleship Squadron of the Atlantic Fleet. Modernised by the 1922–24 refit, she was transferred in 1926 to the Mediterranean Fleet, based in Gibraltar and Grand Harbour, Malta. In early 1928, this duty saw the notorious incident the contemporary press dubbed the "Royal Oak Mutiny".^[16] What began as a simple dispute between Rear-Admiral Bernard Collard and Royal Oak's two senior officers Captain Kenneth Dewar and Commander Henry Daniel over the band at the ship's wardroom dance,^[b] descended into a bitter personal feud that spanned several months.^[17] Dewar and Daniel accused Collard of "vindictive fault-finding" and openly humiliating and insulting them before their crew; in return, Collard countercharged the two with failing to follow orders and treating him "worse than a midshipman".^[18] When Dewar and Daniel wrote letters of complaint to Collard's superior, Vice-Admiral John Kelly, he immediately passed them on to the Commander-in-Chief Admiral Sir Roger Keyes. On realising that the relationship between the two and their flag admiral had irretrievably broken down, Keyes removed all three from their posts and sent them back to England, postponing a major naval exercise.^[19] The press picked up on the story worldwide, describing the affair—with some hyperbole—as a "mutiny".^[20] Public attention reached such proportions as to raise the concerns of the King, who summoned First Lord of the Admiralty William Bridgeman for an explanation.^[20]

External images
	"Syncopated discipline recital on the Royal Oak" The "Mutiny" court-martial was lampooned in the press, as exemplified by this Evening Standard cartoon by David Low

For their letters of complaint, Dewar and Daniel were controversially charged with writing subversive documents.^[21] In a pair of highly publicised courts-martial, both were found guilty and severely reprimanded, leading Daniel to resign from the Navy. Collard himself was criticised for the excesses of his conduct by the press and in Parliament, and on being denounced by Bridgeman as "unfitted to hold further high command",^[22] was forcibly retired from service.^[23]

Of the three, only Dewar escaped with his career,^[24] albeit a damaged one: he remained in the Royal Navy and was promoted to Rear-Admiral the following year, one day before his retirement.^[25] Daniel attempted a career in journalism, but when this and other ventures were unsuccessful, he disappeared into obscurity and poor health in South Africa.^[26] One consequence of the damaging affair was an undertaking from the Admiralty to review the means by which naval officers might bring complaints against the conduct of their superiors.^[22]

Spanish Civil War

During the Spanish Civil War, Royal Oak was tasked with conducting 'non-intervention patrols' of the Iberian Peninsula. On such a patrol and steaming some 30 nautical miles (56 km) east of Gibraltar on 2 February 1937, she came under aerial attack by three aircraft of the Republican forces. They dropped three bombs (two of which exploded) within 3 cables (555 m) of the starboard bow, though causing no damage.^[27] The British chargé d'affaires protested the incident to the Republican Government, which admitted its error and apologised for the attack.^[28][29] Later that same month, while stationed offshore of Valencia on 23 February 1937 during an aerial bombardment by the Nationalists, she was accidentally struck by an anti-aircraft shell fired from a Republican position.^[27] Five men were injured, including the Royal Oak's captain, T.B. Drew.^[30] On this occasion however the British elected not to protest to the Republicans, deeming the incident "an Act of God".^[31] In May 1937, she and HMS Forester escorted SS Habana, a liner carrying Basque child refugees, to England.^[32] In July, as the war in northern Spain flared up, the Royal Oak, along with the battleship HMS Resolution rescued the steamer Gordonia when Spanish nationalist warships attempted to capture her off Santander. She was however unable on 14 July to prevent the seizure of the British freighter Molton when the latter was trying to enter Santander and was eventually captured by the Spanish rebel cruiser Almirante Cervera. The merchantmen had been engaged in the evacuation of refugees.^[33]

This same period saw Royal Oak star alongside fourteen other Royal Navy vessels in the 1937 British film melodrama Our Fighting Navy, the plot of which centres around a coup in the fictional South American republic of Bianco. Royal Oak portrays a rebel battleship El Mirante, whose commander forces a British captain into choosing between his lover and his duty. The film was poorly received by critics, but gained some redemption through its dramatic scenes of naval action.^[34]

Royal Oak returns the body of Queen Maud to Norway

Second World War

In 1938, Royal Oak returned to the Home Fleet and was made flagship of the Second Battleship Squadron based in Portsmouth. On 24 November 1938, she returned the body of the British-born Queen Maud of Norway to a state funeral in Oslo, accompanied by her husband King Haakon VII.^[35] Paying off in December 1938, Royal Oak recommissioned the following June, and in the late summer of 1939 embarked on a short training cruise in the English Channel in preparation for another 30-month tour of the Mediterranean. As hostilities loomed, she was instead dispatched north to Scapa Flow, and was at anchor there when war was declared on 3 September.^[36]

In October, Royal Oak joined the search for the German battleship Gneisenau, which had been ordered into the North Sea as a diversion for the commerce-raiding pocket battleships Deutschland and Graf Spee.^[37] The search was ultimately fruitless, particularly for Royal Oak, whose top speed, by then less than 20 knots (37 km/h), was inadequate to keep up with the rest of the fleet.^[37] On 12 October, Royal Oak returned to the defences of Scapa Flow in poor shape, battered by the North Atlantic storms: many of her Carley floats had been smashed and several of the smaller calibre guns rendered inoperable.^[37][38] The mission had underlined the obsolescence of the twenty-five year old warship.^[37] Concerned that a recent overflight by German reconnaissance aircraft heralded an imminent air attack upon Scapa Flow, Admiral of the Home Fleet Charles Forbes ordered most of the fleet to disperse to safer ports. The Royal Oak however remained behind, her anti-aircraft guns still deemed a useful addition to Scapa's otherwise scarce air defences.^[38]

Loss

Scapa Flow

Main article: Scapa Flow

Scapa Flow

Scapa Flow made a near-ideal anchorage. Situated at the centre of the Orkney Islands off the north coast of Scotland, the natural harbour, large enough to contain the entire Grand Fleet,^[39] was surrounded by a ring of islands separated by shallow channels subject to fast-racing tides. The threat from U-boats had long been realised, and a series of countermeasures were installed during the early years of the First World War.^[40] Blockships were sunk at critical points, and floating booms deployed to block the three widest channels. Operated by tugboats to allow the passage of friendly shipping, it was considered possible—but highly unlikely—that a daring U-boat commander could attempt to race through undetected before the boom was closed.^[40] Two submarines that had attempted infiltration during the war had met unfortunate fates: on 23 November 1914 U-18 was rammed twice before running aground with the capture of her crew,^[41][42] and UB-116 was detected by hydrophone and destroyed with the loss of all hands on 28 October 1918.^[43][44]

Scapa Flow provided the main anchorage for the British Grand Fleet throughout most of the First World War, but in the interwar period this passed to the more conveniently located Rosyth in the Firth of Forth.^[40][45] Scapa Flow was however reactivated with the advent of the Second World War, becoming base to the British Home Fleet.^[40] Its natural and man-made defences, while still strong, were recognised as in need of improvement, and in the early weeks of the war were in the process of being strengthened by the provision of additional blockships.^[46]

Special Operation P: the raid by U-47

Infiltration of Scapa Flow by U-47

Kriegsmarine Commander of Submarines Karl Dönitz devised a plan to attack Scapa Flow by submarine within days of the outbreak of war.^[47] Its goal would be twofold: firstly, that displacing the Home Fleet from Scapa Flow would slacken the British North Sea blockade and grant Germany greater freedom to attack the Atlantic convoys; secondly, the blow would be a symbolic act of vengeance, striking at the same location where the German High Seas Fleet had surrendered and scuttled itself following Germany's defeat in the First World War. Dönitz hand-picked Kapitänleutnant Günther Prien for the task,^[47][c] scheduling the raid for the night of 13/14 October 1939, when the tides would be high and the night moonless.^[47]

Dönitz was aided by high-quality photographs from the recent reconnaissance overflight, which revealed the weaknesses of the defences and an abundance of targets.^[47] He directed Prien to enter Scapa Flow from its east via Kirk Sound, passing to the north of Lamb Holm, a small low-lying island between Burray and Mainland.^[48] Prien initially mistook the more southerly Skerry Sound for the chosen route and his sudden realisation that U-47 was heading for the shallow blocked passage forced him to order a rapid turn to the northeast.^[49] On the surface, and illuminated by a bright display of the aurora borealis,^[50] the submarine threaded between the sunken blockships Seriano and Numidian, grounding itself temporarily on a cable strung from Seriano.^[48] It was briefly caught in the headlights of a taxi onshore, but the driver raised no alarm.^[51][d] On entering the harbour proper at 00:27 on 14 October, Prien entered a triumphant Wir sind in Scapa Flow!!!^[e] in the log and set a south-westerly course for several kilometres before reversing direction.^[48] To his surprise, the anchorage appeared to be almost empty; unknown to him, Forbes' order to disperse the fleet had removed some of the biggest targets. U-47 had been heading directly towards four warships, including the newly commissioned light cruiser Belfast, anchored offshore of Flotta and Hoy 8 km distant, but Prien gave no indication that he had seen them.^[52]

On the reverse course, a lookout on the bridge spotted Royal Oak lying approximately 4,000 m to the north, correctly identified as a battleship of the Revenge class. Mostly hidden behind her was a second ship, only the bow of which was visible to U-47. Prien mistook it to be a battlecruiser of the Renown class, German intelligence later labelling it Repulse.^[48] It was in fact the World War I seaplane tender Pegasus.^[53]

Site of attack on Royal Oak, with oil risen from the wreck visible

At 00:58 U-47 fired a salvo of three torpedoes from its bow tubes, a fourth lodging in its tube. Two failed to find a target, but a single torpedo struck the bow of Royal Oak at 01:04, shaking the ship and waking the crew.^[54] Little visible damage was received, though the starboard anchor chain was severed, clattering noisily down through its slips. Initially, it was suspected that there had been an explosion in the ship's forward inflammable store, used to store materials such as kerosene. Mindful of the unexplained explosion that had destroyed HMS Vanguard in Scapa Flow in 1917,^[42][f] an announcement was made over the Royal Oak's tannoy system to check the magazine temperatures,^[g] but many sailors returned to their bunks, unaware that the ship was under attack.^[54][55]

Prien turned his submarine and attempted another shot via his stern tube, but this too missed. Reloading his bow tubes, he doubled back and fired a salvo of three torpedoes, all at Royal Oak,^[48] and this time he was successful: at 01:16 all three struck the battleship in quick succession at her amidships.^[56][57]

A series of explosions ran through the ship, followed by an inrush of seawater. The ship immediately listed some 15°, sufficient to push the open starboard-side portholes below the waterline.^[h] She soon rolled further onto her side to 45°, hanging there for several minutes before disappearing beneath the surface at 01:29, 13 minutes after Prien's second strike.^[58] 833 men died with the ship, including Rear-Admiral Henry Blagrove, commander of the Second Battleship Division. The admiral's wooden gig, moored alongside, was dragged down with Royal Oak.

Rescue efforts

The tender Daisy 2, skippered by John Gatt RNR, had been tied up for the night to Royal Oak's port side. As the sinking battleship began to list to starboard, Gatt ordered Daisy 2 to be cut loose, his vessel becoming briefly caught on Royal Oak's rising anti-torpedo bulge and lifted from the sea before freeing herself.^[60]

Many of Royal Oak's crew that had managed to jump from the sinking ship were dressed in little more than their nightclothes and were unprepared for the chilling water. A thick layer of fuel oil coated the surface, filling men's lungs and stomachs and hampering their efforts to swim. Of those who attempted the 800-metre swim to the nearest shore, only a handful survived.^[61] Gatt lit the lights of Daisy 2, and he and his crew managed to pull 386 men from the water, including Royal Oak's commander, Captain William Benn.^[62] The rescue efforts continued for another two and a half hours until nearly 4:00 am, when Gatt abandoned the search for more survivors and took those he had to Pegasus. Although aided by boats from Pegasus and the harbour,^[63] he was responsible for rescuing almost all the survivors, an act for which he would be awarded the Distinguished Service Cross,^[64] the only military award made by the British in connection with the disaster.^[65]

Aftermath

The crew of Scharnhorst saluting U-47 on its return

The British were initially confused as to the cause of the sinking, suspecting either an on-board explosion or aerial attack.^[40] Once it was realised that a submarine attack was the most likely explanation, steps were rapidly made to seal the anchorage, but U-47 had already escaped and was on its way back to Germany. The BBC released news of the sinking by late morning on 14 October, and its broadcasts were received by the German listening services and by U-47 itself. Divers sent down on the morning after the explosion discovered remnants of a German torpedo, confirming the means of attack. On 17 October First Lord of the Admiralty Winston Churchill officially announced the loss of Royal Oak to the House of Commons, first conceding that the raid had been "a remarkable exploit of professional skill and daring", but then declaring that the loss would not materially affect the naval balance of power.^[66] An Admiralty Board of Inquiry convened between 18 and 24 October to establish the circumstances under which the anchorage had been penetrated. In the meantime, the Home Fleet was ordered to remain at safer ports until security issues at Scapa could be addressed.^[67]

The Nazi Propaganda Ministry was quick to capitalise on the successful raid,^[6][68] and radio broadcasts by the popular journalist Hans Fritzsche displayed the triumph felt throughout Germany.^[69] Prien and his crew reached Wilhelmshaven at 11:44 on 17 October and were immediately greeted as heroes, learning that Prien had been awarded the Iron Cross First Class, and each man of the crew the Iron Cross Second Class.^[70] Hitler sent his personal plane to bring the crew to Berlin, where he further invested Prien with the Knight's Cross of the Iron Cross. This decoration, made for the first time to a German naval officer, later became the customary decoration for successful U-Boat commanders. Dönitz was rewarded by promotion from Commodore to Rear-Admiral and was made Flag Officer of U-Boats.^[70]

Prien was nick-named "The Bull of Scapa Flow" and his crew decorated U-47's conning tower with a snorting bull mascot, later adopted as the emblem of the 7th U-boat Flotilla. He found himself in demand for radio and newspaper interviews,^[70] and his 'autobiography' was published the following year, titled Mein Weg nach Scapa Flow.^[i] Ghost-written by a German journalist, in the post-war years certain of its claims relating to the events of October 1939 were brought into question.^[71][72]

The British Admiralty's official report into the disaster condemned the defences at Scapa Flow, and censured Sir Wilfred French, Admiral Commanding Orkney and Shetland, for their unprepared state. French was placed on the retired list,^[73] despite having warned the previous summer of Scapa Flow's deficient anti-submarine defences, and volunteering to bring a small ship or submarine himself past the blockships to prove his point.^[74]

Churchill Barrier 1, now blocking Kirk Sound, Prien's entry into Scapa Flow

On Churchill's orders, the eastern approaches to Scapa Flow were sealed with concrete causeways linking Lamb Holm, Glimp Holm, Burray and South Ronaldsay to the Orkney Mainland. Constructed largely by Italian prisoners of war,^[75] the Churchill Barriers, as they became known, were essentially complete by September 1944, though they were not opened officially until just after VE Day in May 1945.^[76] They now form part of the transport infrastructure of the Orkneys, carrying the A961 road between the islands.

In the years that followed, a rumour circulated that Prien had been guided into Scapa by one Alfred Wehring, a German agent living in Orkney in the guise of a Swiss watchmaker named Albert Oertel.^[77] Following the attack, 'Oertel' escaped with the submarine B-06 back to Germany.^[78] This account of events originated as an article by the journalist Curt Riess in the 16 May 1942 issue of the American magazine Saturday Evening Post and was later embellished by other authors.^[77][79] Post-war searches through German and Orcadian archives have however failed to find any evidence for the existence of either Oertel, Wehring or a submarine named B-06, and the story is now held to be wholly fictitious.^[80][81]

Wreck

Status as war grave

Memorial in St Magnus', featuring Royal Oak's bell

Despite the relatively shallow water in which she sank, the majority of bodies could not be recovered from Royal Oak. Marked by a buoy at , the wreck has been designated a war grave and all diving or other unauthorised forms of exploration are prohibited under the Protection of Military Remains Act 1986.^[82] In clear water conditions, the upturned hull can be seen reaching to within 5 m of the surface. The brass letters that formed Royal Oak's name were removed as a keepsake by a recreational diver in the 1970s. They were returned almost twenty years later and are now displayed in the Scapa Flow visitors' centre in Lyness on Hoy. The Royal Oak's loss is commemorated in an annual ceremony in which Royal Navy divers place the White Ensign underwater at her stern.^[83] A memorial at St Magnus' Cathedral in nearby Kirkwall displays a plaque dedicated to those who lost their lives; beneath which a book of remembrance lists their names. The ship's bell was recovered in the 1970s and after being restored was added to the memorial in St Magnus'.^[84] A number of bodies, including some that could not be identified, were interred at the naval cemetery in Lyness.^[85]

Environmental concerns

Royal Oak sank with up to 3,000 tons of fuel oil aboard. The oil leaked from the corroding hull at an increased rate during the 1990s and concerns about the environmental impact led the Ministry of Defence to consider plans for extracting it.^[86] Royal Oak's status as a war grave required that surveys and any proposed techniques for removing the oil be handled sensitively: plans in the 1950s to raise and salvage the wreck had been dropped due to public opposition.^[87] In addition to the ethical concerns, poorly-managed efforts could destabilise the wreck, resulting in a mass release of the remaining oil;^[88] the ship moreover containing many tons of unexploded ordnance.^[89]

External images
	Sonogram of Royal Oak High-resolution images showed the wreck in greater detail than had been seen before.[89]

The MOD commissioned the specialist Archaeological Dive Unit Survey team to carry out a series of multi-beam sonar surveys to image the wreck and appraise its condition.^[90] The high-resolution sonograms showed Royal Oak to be lying almost upside down with her top works forced into the seabed. The tip of the bow had been blown off by Prien's first torpedo and a gaping hole on the starboard flank was the result of the triple strike from his second successful salvo.^[89][91] Following several years of delays, the task of pumping off the remaining oil has begun and by 2006, all double bottom tanks had been cleared. A 2007 test scheme to remove oil from the inner wing tanks with cold cutting equipment was successful and the MOD plans to continue efforts to remove the remaining accessible oil during successive years.^[89] Difficult operating conditions limit salvage work to the summer months.

Notes

Citations

References

External links

• hmsroyaloak.co.uk Website dedicated to the ship and its crew
• Maritimequest photo gallery
• Ship model plans: HMS battleship Royal Oak
• uboat.net: The Bull of Scapa Flow
• u47.org Detailed account of the attack
• Archive newsreel footage of Prien's return (German)
• http://www.adus.org.uk/royaloak.html

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