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Operation Rheinubung : Bismarck’s Last & Only Mission

Bismarck (German Battleship, 1940-41) Afloat just after launching, at the Blohm & Voss shipyard, Hamburg, Germany, 14 February 1939.

Operation Rheinubung : Bismarck’s Last & Only Mission

“Given the uneven relation of forces I am of the opinion that I should have to sacrifice myself sooner or later. I have closed out my private life and am determined to carry out the assignment given to me honorably, one way or another.” – Admiral Johann Günther Lütjens on his

On the 16th of May Lütjens reported that Bismarck and Prinz Eugen were fully prepared for Operation Rheinübung so he was ordered to proceed with the mission on the evening of 19 May. As part of the operational plans, a group of eighteen supply ships would be positioned to support Bismarck and Prinz Eugen. Four U-boats would be placed along the convoy routes between Halifax and Britain to scout for the raiders.

By the start of the operation, Bismarck’s crew had increased to 2,221 men.

RAF aerial reconnaissance photo showing Bismarck anchored (centre right) in Grimstadfjord, Norway

This included an admiral’s staff of nearly 65 and a prize crew of 80 sailors, who could be used to crew transports captured during the mission. At 02:00 on 19 May, Bismarck departed Gotenhafen and made for the Danish straits. She was joined at 11:25 by Prinz Eugen, who had departed the previous night. The two ships were escorted by three destroyers, the Z10 Hans Lody, Z16 Friedrich Eckoldt, and Z23. The Luftwaffe also provided air cover during the voyage out of German waters. At around noon on the 20th of May, Lindemann informed the ship’s crew via loudspeaker of the ship’s mission. At approximately the same time, a group of ten or twelve Swedish aircraft flying reconnaissance encountered the German force and reported its position and heading.

An hour later, the German flotilla encountered the Swedish cruiser HSwMS Gotland and the cruiser shadowed the Germans for two hours in the Kattegat.

Gotland transmitted a report to naval headquarters, stating:

“Two large ships, three destroyers, five escort vessels, and 10–12 aircraft passed Marstrand, course 205°/20′.”

Lütjens and Lindemann believed operational secrecy had been lost but were unconcerned. The report eventually made its way to Captain Henry Denham, the British naval attaché to Sweden, who transmitted the information to the Admiralty. The code-breakers at Bletchley Park confirmed that an Atlantic raid was imminent, as they had decrypted reports that Bismarck and Prinz Eugen had taken on prize crews and requested additional navigational charts from headquarters. A pair of Supermarine Spitfires searched the Norwegian coast for the flotilla.

The Swedish airplane cruiser HMS Gotland in the Caribbean.

German aerial reconnaissance confirmed that one aircraft carrier, three battleships, and four cruisers remained at anchor in the main British naval base at Scapa Flow, which made Lütjens think the British were unaware of the operation. On the evening of 20 May, Bismarck and the rest of the flotilla reached the Norwegian coast; the minesweepers were detached and the two raiders and their destroyer escorts continued north. The following morning, radio-intercept officers on board Prinz Eugen picked up a signal ordering British reconnaissance aircraft to search for two battleships and three destroyers northbound off the Norwegian coast. At 7:00 on the 21st, the Germans spotted four unidentified aircraft, which quickly departed. Shortly after 12:00, the flotilla reached Bergen and anchored at Grimstadfjord, where the ships’ crew painted over the Baltic camouflage with the standard grey worn by German warships operating in the Atlantic.

When Bismarck was in Norway, a pair of Bf 109 fighters circled overhead to protect her from British air attacks, but Flying Officer Michael Suckling managed to fly his Spitfire directly over the German flotilla at a height of 8,000m  and take photos of Bismarck and her escorts. Upon receipt of the information, Admiral John Tovey ordered the battlecruiser HMS Hood, the newly commissioned battleship HMS Prince of Wales, and six destroyers to reinforce the pair of cruisers that were patrolling the Denmark Strait. The rest of the Home Fleet was placed on high alert in Scapa Flow. Eighteen bombers were dispatched to attack the Germans, but they were unable to find the German warships and attack them.

Bismarck did not replenish her fuel stores in Norway, as her operational orders did not require her to do so. She had left port with 200 long tons short of a full load, and had since expended another 980 long tons on the voyage from Gotenhafen. Prinz Eugen took on 752 long tons of fuel. At 19:30 on 21 May, Bismarck, Prinz Eugen, and the three escorting destroyers left Bergen. At midnight, when the ship’s were in the open sea, heading towards the Arctic Ocean, Raeder disclosed the operation to Hitler, who reluctantly consented to the raid. The three escorting destroyers were detached at 04:14 on 22 May, At around 12:00, Lütjens ordered his two ships to turn toward the Denmark Strait to attempt the break-out into the open Atlantic.

By 04:00 on 23 May, Lütjens ordered Bismarck and Prinz Eugen to increase speed to 27 knots to make a run through the Denmark Strait. Upon entering the Strait, both ships activated their FuMO radar detection equipment sets. Bismarck led Prinz Eugen by about 700 m. At 19:22, hydrophone and radar operators aboard the German warships detected the cruiser HMS Suffolk at a range of approximately 12,500 m. Prinz Eugen’s radio-intercept team decrypted the radio signals being sent by Suffolk and learned that their location had been reported.

Lütjens gave permission for Prinz Eugen to engage Suffolk, but the captain of the German cruiser could not clearly make out his target and so held fire. Suffolk quickly retreated to a safe distance and shadowed the German ships. At 20:30, the heavy cruiser HMS Norfolk joined Suffolk, but approached the German raiders too closely. Lütjens ordered his ships to engage the British cruiser; Bismarck fired five salvoes, three of which straddled Norfolk and rained shell splinters on her decks. The cruiser laid a smoke screen and fled into a fog bank, ending the brief engagement. The concussion from Bismarck’s guns firing disabled Bismarck’s FuMO 23 radar set; this prompted Lütjens to order Prinz Eugen to take station ahead so she could use her functioning radar to scout for the formation.

At around 22:00, Lütjens ordered Bismarck to make a 180-degree turn in an effort to surprise the two heavy cruisers shadowing him. Although Bismarck was visually obscured in a rain squall, Suffolk’s radar quickly detected the maneuver, allowing the cruiser to evade. The cruisers remained on station through the night, continually relaying the location and bearing of the German ships. The harsh weather broke on the morning of 24 May, revealing a clear sky. At 05:07, hydrophone operators aboard Prinz Eugen detected a pair of unidentified vessels approaching the German formation at a range of 20 nmi reporting:

“Noise of two fast-moving turbine ships at 280° relative bearing!”

The Royal Navy during the Second World War The BISMARCK seen in the distance from a Fairey Swordfish from the aircraft carrier HMS VICTORIOUS just before the torpedo attack.

At 05:45 on 24 May, German lookouts spotted smoke on the horizon and this turned out to be from HMS Hood and HMS Prince of Wales under the command of Vice Admiral Lancelot Holland.

Lütjens ordered his ships’ crews to battle stations.

By 05:52, the range had fallen to 26,000 m and Hood opened fire, followed by the Prince of Wales a minute later. Hood engaged Prinz Eugen, which Hood thought to be Bismarck, while Prince of Wales fired on Bismarck. Adalbert Schneider, the first gunnery officer aboard Bismarck, twice requested permission to return fire, but Lütjens hesitated.

Lindemann intervened and demanded permission to fire from Lütjens, who relented and at 05:55 ordered his ships to engage the British.

The British ships approached the German ships head on, which permitted them to use only their forward guns, Bismarck and Prinz Eugen could fire full broadsides. Several minutes after opening fire, Holland ordered a 20° turn to port, which would allow his ships to engage with their rear gun turrets. Both German ships concentrated their fire on Hood. About a minute after opening fire, Prinz Eugen scored a hit with a high-explosive 8.0 inch shell, the explosion started a large fire, which was quickly extinguished.

After firing three four-gun salvoes, Schneider had found the range to Hood and he immediately ordered rapid-fire salvoes from Bismarck’s eight 15-inch guns. He also ordered the ship’s 15 cm secondary guns to engage the Prince of Wales. Holland then ordered a second 20° turn to port, to bring his ships on a parallel course with Bismarck and Prinz Eugen. Lütjens ordered Prinz Eugen to shift fire and target the Prince of Wales, to keep both of his opponents under fire. Within a few minutes, Prinz Eugen scored a pair of hits on the battleship that started a small fire.

HMS HOOD (HU 50190) HMS HOOD going into action against the German battleship BISMARCK and battlecruiser Prinz Eugen, 24 May 1941. This image taken from HMS PRINCE OF WALES was the last photo ever taken of HMS HOOD. Copyright: © IWM.

Lütjens then ordered Prinz Eugen to drop behind Bismarck, so she could continue to monitor the location of Norfolk and Suffolk, which were still 10 to 12 nmi to the east. At 06:00, Hood was completing the second turn to port when Bismarck’s fifth salvo hit. Two of the shells landed short, striking the water close to the ship, but at least one of the 38 cm armor-piercing shells struck Hood and penetrated her deck armor.

Hood’s rear ammunition magazine was hit and detonated (110 long tons) of cordite propellant causing a massive explosion that broke the back of the ship between the main mast and the rear funnel, the forward section continued to move forward briefly before the water caused the bow to rise into the air at a steep angle. The stern also rose as water rushed into the ripped-open compartments.

In only eight minutes of firing, Hood had disappeared, taking all but three of her crew of 1,419 men with her.

Hood during and after the explosion; sketch prepared by Captain JC Leach (commanding Prince of Wales) for the second board of enquiry in 1941, and photo from the Bundesarchiv. The column of smoke or flame that erupted from the vicinity of the mainmast (immediately before a huge detonation obliterated the after part of the ship from view) is believed to have been the result of a cordite fire venting through the engine-room ventilators.

Bismarck then shifted fire to HMS Prince of Wales.

The British battleship scored a hit on Bismarck with her sixth salvo. But the German ship found her mark with her first salvo. One of the shells struck the bridge on Prince of Wales, though it did not explode and instead exited the other side. As a result, killing everyone in the ship’s command center except Captain John Leach. The ship’s commanding officer, and one other.

The two German ships continued to fire on Prince of Wales, causing damage. The Guns on Prince of Wales malfunctioned on the ship from the beginning of the battle. Despite the technical faults in the main battery, Prince of Wales scored hits on Bismarck in the engagement. The first struck her in the forecastle above the waterline but low enough to allow the crashing waves to enter the hull. The second shell struck below the armored belt and exploded on contact with the torpedo bulkhead, completely flooding a turbo-generator room and partially flooding an adjacent boiler room. The third shell passed through one of the boats carried aboard the ship and then went through the floatplane catapult without exploding.

At 06:13, Leach gave the order to retreat as only five of his ship’s ten 14 in guns were still firing and his ship had sustained significant damage. Prince of Wales made a 160° turn and laid a smoke screen to cover her withdrawal. The Germans ceased fire as the range widened. Though Lindemann strongly advocated chasing Prince of Wales and destroying her, Lütjens would not as Bismarck was already damaged and he also obeyed operational orders to shun any avoidable engagement with enemy forces that were not protecting a convoy, firmly rejecting the request, and instead ordered Bismarck and Prinz Eugen to head for the North Atlantic.

In the engagement, Bismarck had fired 93 armor-piercing shells and had been hit by three shells in return. The forecastle hit allowed 1,000 to 2,000 tons of water to flood into the ship which contaminated fuel oil stored in the bow. Lütjens refused to reduce speed to allow damage control teams to repair the shell hole which widened and allowed more water into the ship. The second hit caused some additional flooding. Shell-splinters from the second hit also damaged a steam line in the turbo-generator room, but this was not serious, as Bismarck had sufficient other generator reserves. The combined flooding from these two hits caused a 9-degree list to port and a 3-degree trim by the bow.

After the engagement, Lütjens reported:

“Battlecruiser, probably Hood, sunk. Another battleship, King George V or Renown, turned away damaged. Two heavy cruisers maintain contact.”

At 08:01, he transmitted a damage report and his intentions to detach Prinz Eugen for commerce raiding and to make Saint-Nazaire for repairs. Shortly after 10:00, Lütjens ordered Prinz Eugen to fall behind Bismarck to determine the severity of the oil leakage from the bow. After confirming streams of oil on both sides of Bismarck’s wake, Prinz Eugen returned to the forward position. About an hour later, a British Short Sunderland flying boat reported the oil slick to Suffolk and Norfolk, which had been joined by the damaged Prince of Wales. Rear Admiral Frederic Wake-Walker, the commander of the two cruisers, ordered the Prince of Wales to remain behind his ships.

Prime Minister Winston Churchill ordered all warships in the area to join the pursuit of Bismarck and Prinz Eugen.

Tovey’s Home Fleet was steaming to intercept the German raiders, but on the morning of 24 May was still over 350 nmi away. The Admiralty ordered the light cruisers Manchester, Birmingham, and Arethusa to patrol the Denmark Strait in case Lütjens attempted to retrace his route. The battleship Rodney, which had been escorting RMS Britannic and was due for a refit in the Boston Navy Yard, joined Tovey.

Two old Revenge-class battleships were ordered into the hunt: Revenge, from Halifax, and Ramillies, which was escorting Convoy HX 127. In all, six battleships and battlecruisers, two aircraft carriers, thirteen cruisers, and twenty-one destroyers were committed to finding Bismarck. By around 17:00, the crew aboard Prince of Wales restored nine of her ten main guns to working order, which permitted Wake-Walker to place her in the front of his formation to attack Bismarck if the opportunity arose.

With the weather worsening, Lütjens attempted to detach Prinz Eugen. The cruiser was successfully detached at 18:14. Bismarck turned around to face Wake-Walker’s formation, forcing Suffolk to turn away at high speed. The Prince of Wales fired twelve salvos at Bismarck, which responded with nine salvos, none of which hit. The action diverted British attention and permitted Prinz Eugen to slip away. After Bismarck resumed her previous heading, Wake-Walker’s three ships took up station on Bismarck’s port side.

Although Bismarck had been damaged in the engagement and forced to reduce speed, she was still capable of reaching 27 to 28 knots the maximum speed of Tovey’s King George V. Unless Bismarck could be slowed, the British would be unable to prevent her from reaching Saint-Nazaire. Shortly before 16:00 on 25 May, Tovey detached the aircraft carrier HMS Victorious and four light cruisers to shape a course that would position her to launch her torpedo bombers. At 22:00, Victorious launched the strike, which comprised six Fairey Fulmar fighters and nine Fairey Swordfish torpedo bombers of 825 Naval Air Squadron, led by Lt Cdr Eugene Esmonde. The inexperienced aviators nearly attacked Norfolk and the U.S. Coast Guard cutter USCGC Modoc on their approach; the confusion alerted Bismarck’s anti-aircraft gunners.

Bismarck also used her main and secondary batteries to fire at maximum depression to create giant splashes in the paths of the incoming torpedo bombers. None of the attacking aircraft were shot down. Bismarck evaded eight of the torpedoes launched at her, but the ninth struck amidships on the main armored belt, throwing one man into a bulkhead and killing him and injuring five others.

The explosion also caused minor damage to electrical equipment. The ship suffered more serious damage from maneuvers to evade the torpedoes, rapid shifts in speed and course loosened collision mats, which increased the flooding from the forward shell hole and eventually forced abandonment of the port number 2 boiler room. This loss of a second boiler, combined with fuel losses and increasing bow trim:

Forced Bismarck to slow to 16 knots.

Divers repaired the collision mats in the bow, after which speed increased to 20 knots which the speed the command staff determined was the most economical for the voyage to occupied France with the damage.

Shortly after the Swordfish departed from the scene, Bismarck and Prince of Wales engaged each other . Neither scored a hit. Bismarck’s damage control teams resumed work after the short engagement. By the morning on 25 May, the danger had passed. The ship slowed to 12 knots to allow divers to pump fuel from the forward compartments to the rear tanks.

As the pursuit entered open waters, Wake-Walker’s ships were compelled to zig-zag to avoid German U-boats that might be in the area. This required the ships to steam for ten minutes to port, then ten minutes to starboard, to keep the ships on the same base course. For the last few minutes of the turn to port, Bismarck was out of range of Suffolk’s radar.

At 03:00 on 25 May, Lütjens ordered an increase to maximum speed, which at this point was a respectful 28 knots. He then ordered the ship to circle away to the west and then north. This maneuver coincided with the period during which his ship was out of radar range, Bismarck successfully broke radar contact and circled back behind her pursuers. Suffolk’s captain assumed that Bismarck had broken off to the west and attempted to find her by also steaming west. After half an hour, he informed Wake-Walker, who ordered the three ships to disperse at daylight to search visually.

The Royal Navy search became desperate.

As many of the British ships were low on fuel. HMS Victorious and her escorting cruisers were sent west, Wake-Walker’s ships continued to the south and west, and Tovey continued to steam toward the mid-Atlantic. Force H, with the aircraft carrier Ark Royal and steaming up from Gibraltar, was still at least a day away. Unaware that he had shaken off Wake-Walker, Lütjens sent long radio messages to Naval Group West headquarters in Paris. The signals were intercepted by the British, from which bearings were determined. They were wrongly plotted on board King George V, leading Tovey to believe that Bismarck was heading back to Germany through the Iceland-Faroe gap, which kept his fleet on the wrong course for seven hours. By the time the mistake had been discovered, Bismarck had put a sizable gap between herself and the British ships.

The aircraft carrier HMS Ark Royal with a flight of Swordfish overhead

British code-breakers were able to decrypt some of the German signals, including an order to the Luftwaffe to provide support for Bismarck making for Brest. The French Resistance provided the British with confirmation that Luftwaffe units were relocating there. Tovey could now turn his forces toward France to converge in areas through which Bismarck would have to pass.A squadron of Coastal Command PBY Catalinas based out of RAF Castle Archdale in Northern Ireland joined the search, covering areas where Bismarck might head in the attempt to reach occupied France. At 10:30 on 26 May, a Catalina  located her, some 690 nmi northwest of Brest. At her current speed, she would have been close enough to reach the protection of U-boats and the Luftwaffe in less than a day. Most British forces were not close enough to stop her.

The only possibility for the Royal Navy was HMS Ark Royal with Force H, under the command of Admiral James Somerville. Victorious, Prince of Wales, Suffolk and Repulse were forced to break off the search due to fuel shortage; the only heavy ships remaining apart from Force H were King George V and Rodney, but they were too distant. Ark Royal’s Swordfish were already searching nearby when Catalina found her. Several torpedo bombers also located the battleship, about 60 nmi away from Ark Royal. Somerville ordered an attack as soon as the Swordfish returned and were rearmed with torpedoes. He detached the cruiser Sheffield to shadow Bismarck, though Ark Royal’s aviators were not informed of this. As a result, the Swordfish, which were armed with torpedoes equipped with new magnetic detonators, accidentally attacked Sheffield. The magnetic detonators failed to work properly and Sheffield emerged unscathed.

Upon returning to Ark Royal, the Swordfish loaded torpedoes equipped with contact detonators. The second attack comprised fifteen aircraft and was launched. At 20:47, the torpedo bombers began their attack descent through the clouds. As the Swordfish approached, Bismarck fired her main battery at Sheffield, straddling the cruiser with her second salvo. Shell fragments rained down on Sheffield, killing three men and wounding several others. Sheffield quickly retreated under cover of a smoke screen. The Swordfish then attacked; Bismarck began to turn violently as her anti-aircraft batteries engaged the bombers. One torpedo hit amidships on the port side, just below the bottom edge of the main armor belt. The force of the explosion was largely contained by the underwater protection system and the belt armor but some structural damage caused minor flooding.

The second torpedo struck Bismarck in her stern on the port side, near the port rudder shaft. As a result of the strike, the coupling on the port rudder assembly was badly damaged and the rudder became locked in a 12° turn to port.

The explosion also caused much shock damage. The crew eventually managed to repair the starboard rudder but the port rudder remained jammed. A suggestion to sever the port rudder with explosives was dismissed by Lütjens, as damage to the screws would have left the battleship helpless.

With the port rudder jammed, Bismarck was now steaming in a large circle, unable to escape from Tovey’s forces. Though fuel shortages had reduced the number of ships available to the British, the battleships King George V and Rodney were still available, along with the heavy cruisers Dorsetshire and Norfolk.

Lütjens signaled headquarters at 21:40 on the 26th:

“Ship unmanoeuvrable. We will fight to the last shell. Long live the Führer.”

As darkness fell, Bismarck briefly fired on Sheffield, though the cruiser quickly fled. Sheffield lost contact in the low visibility and Captain Philip Vian’s group of five destroyers was ordered to keep contact with Bismarck through the night. The ship’s encountered Bismarck at 22:38; the battleship quickly engaged them with her main battery.

After firing three salvos, she straddled the Polish destroyer ORP Piorun. The destroyer continued to close the range until a near miss at around 12,000 m forced her to turn away. Throughout the night and into the morning, Vian’s destroyers attacked Bismarck, illuminating her with star shells and firing dozens of torpedoes, none of which hit. Between 05:00 and 06:00, Bismarck’s crew attempted to launch one of the Arado 196 float planes to carry away the ship’s war diary, footage of the engagement with Hood, and other important documents. The third shell hit from Prince of Wales had damaged the steam line on the aircraft catapult, rendering it inoperative. As it was not possible to launch the aircraft, it had become a fire hazard, and was pushed overboard.

After daybreak on 27 May, King George V led the attack against Bismarck. Rodney followed off her port quarter; Tovey intended to steam directly at Bismarck until he was about 8 nmi away. At that point, he would turn south to put his ships parallel to his target. At 08:43, lookouts on King George V spotted her, some 23,000 m away. Four minutes later, Rodney’s two forward turrets, comprising six 16 inch guns, opened fire, then King George V’s 14 inch guns began firing. Bismarck returned fire at 08:50 with her forward guns; with her second salvo, she straddled Rodney.

Lütjens’ final message, informing the German command of his intention to fight to the last against the enemy.

As the range fell, the ships’ secondary batteries joined the battle. Norfolk and Dorsetshire closed and began firing with their 8 inch guns. At 09:02, a 16-inch shell from Rodney struck Bismarck’s forward superstructure, killing hundreds of men and severely damaging the two forward turrets. According to survivors, this salvo probably killed both Lindemann and Lütjens. The main fire control director was also destroyed by this hit.

A second shell from this salvo struck the forward main battery, which was disabled, though it would manage to fire one last salvo. Lieutenant von Müllenheim-Rechberg, in the rear control station, took over firing control for the rear turrets. He managed to fire three salvos before a shell destroyed the gun director, disabling his equipment. He gave the order for the guns to fire independently, but very  quickly all four main battery turrets had been put out of action. One of Bismarck’s shells exploded 20 feet off Rodney’s bow and became the closest Bismarck came to a direct hit on her opponents in the battle.

Rodney fires salvos at Bismarck.

By 10:00, Tovey’s two battleships had fired over 700 main battery shells, many at very close range. Rodney closed to 2,700 m  point-blank range for guns of her size, and continued to fire. Bismarck had been reduced to a sinking wreck on fire from stem to stern. She was slowly settling by the stern from uncontrolled flooding with a 20 degree list to port. Tovey would not cease fire until the Germans struck their ensigns or it became clear they were abandoning ship.

Overall the four British ships fired more than 2,800 shells at Bismarck, and scored more than 400 hits.

The heavy gunfire at virtually point-blank range devastated the superstructure and the sections of the hull that were above the waterline, causing very heavy casualties, Rodney fired two torpedoes from her port-side tube and got a hit, the only instance in history of one battleship torpedoing another.

At around 10:20, running low on fuel, Tovey ordered the cruiser Dorsetshire to sink Bismarck with torpedoes and ordered his battleships back to port.

Dorsetshire fired a pair of torpedoes into Bismarck’s starboard side, one of which hit. Dorsetshire then moved around to her port side and fired another torpedo, which also hit. By the time these torpedo attacks took place, the ship was already listing so badly that the deck was already underwater partly, Bismarck disappeared beneath the surface at 10:40 after being finished off by torpedoes from Dorsetshire.

Survivors from the Bismarck are pulled aboard HMS Dorsetshire (40) on 27 May 1941.

Around 400 men were now in the water of Dorsetshire and the destroyer Maori moved in and lowered ropes to pull the survivors aboard. At 11:40, Dorsetshire’s captain ordered the rescue effort abandoned after lookouts spotted a U-boat. Dorsetshire had rescued 85 men and Maori had picked up 25 by the time they left the scene. A U-boat was in the area but had no torpedoes left, later reached the survivors and found three men, and a German trawler rescued another two. Out of a crew of over 2,200 men, only 114 survived.

Operation Rheinubung : Bismarck’s Last & Only Mission Written by Harry Gillespie

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