German Submarine U-47 in World War II

Introduction

The German Type VIIB U-boat of the Kriegsmarine U-47 is one of the best-known submarines of World War II. Kapitänleutnant Günther Prien received enormous publicity after U-47 entered the British Home Fleet's base at Scapa Flow in October 1939 and scuttled the British battleship HMS Royal Oak. This article examines U-47’s design, its qualities as a standout in the Kriegsmarine’s force, and its important contributions to aspects of the Second World War, most notably the Battle of the Atlantic. U-47 was the thirteenth most successful U-boat in the entire war of 1939 to 1945 when measured by ships sunk over its career. Its tale is one of technological wizardry, tactical genius, and the grim realities of undersea warfare.

Design of U-47

Origins and Specifications

U-47 was a Type VIIB U-boat, a development of the Type VIIA, which had served in the Spanish Civil War, but a design still limited by the Kriegsmarine's focus on medium-sized, general-purpose U-boats. U-47 was constructed with the intent of infiltrating and disrupting Allied shipping in the North Atlantic; she was laid down on 25 February 1937 at Friedrich Krupp Germaniawerft in Kiel and commissioned on 17 December 1938.

The Type VIIB had a surface displacement of 753t and 857t submerged, and a length of 66.5m, a beam of 6.20m, and a draught of 4.74m. Propelled by two MAN diesel engines for cruising on the surface (totaling 2,800–3,200 horsepower), and two electric motors for use while submerged (750 horsepower), the boat could operate at a maximum speed of 17.9 knots while surfaced, and at 8 knots when submerged. The type VIIB's range was about 8,700 nautical miles at 10 knots surfaced (93 if supercharged 6,200 km at 19 km/h) via a larger saddle tanks than the VIIA.

U-47 was also supplied with 14 torpedoes for the bow and one for the stern as well as an 88mm SK C/35 naval gun and a 20mm anti-aircraft gun for surface combat. With the addition of twin rudders, which made it much more maneuverable, and a sturdy pressure hull, the Type VIIB could dive to 820 feet, which proved a significant edge in avoiding depth charges. These attributes made U-47 a highly versatile and dangerous commerce raider and naval raider.

Technological and Tactical Advantages

Type VIIB was a significant improvement over previous models due to the improvements in the fuel capacity, manoeuvrability, as well as the torpedo load. These advancements also enabled longer patrols and more aggressive tactics, which dovetailed with Admiral Karl Dönitz’s strategy to use U-boats to strangle Allied supply lines with coordinated “wolfpack” tactics. The design of U-47 emphasized simplicity and reliability, which proved that the submarine could be effective on the harsh North Atlantic. Smaller than your average U-boat, it was harder to pick up on sonar than the larger submarines but had more than enough firepower to make life hell for both merchant and navy vessels.

The boat’s ability to dive quickly and deep made it especially difficult for Allied escorts to send her to the bottom. But life aboard was punishing with tight spaces, poor sanitation (one of the two toilets doubled as a food locker) and patrols that often lasted two months. The boats with a crew of 44-47 men, most under the command of capable captains to which Prien belonged, all served under difficult and demanding circumstances, depending on training and discipline to carry out difficult missions.

What Made U-47 Special

Leadership of Günther Prien

U-47’s legend was as much a product of its commander, Günther Prien, a charismatic and capable officer personally selected by Dönitz for high-stakes missions. Bold and resourceful decisions on the part of Prien’s command worked to the benefit of U-47. He was known as “Der Stier von Scapa Flow” (The Bull of Scapa Flow) thanks to his daring attack on the British naval base, and the snorting bull badge painted on U-47’s conning tower became the 7th U-boat Flotilla’s emblem. But Prien’s ability to motivate his crew and steer through deadly seas made U-47 a standout.

Strategic Impact

The U-47’s sorties were a part of the Kriegsmarine’s policy of unrestricted submarine warfare, an attempt to disrupt Britain’s supply chains. In this way the U-47 was able to damage to British logistics by attacking merchant shipping and navy assets and to compel Britain to strip some of her resources from other operations in order to fight and counter the U-boats. Its achievement in infiltrating Scapa Flow, a heavily protected anchorage, revealed weaknesses in British naval defenses and provided a morale boost to the Germans early in the war. The psychological effects of U-47’s attacks, and the sinking of the Royal Oak in particular, reinforced the U-boat’s function as an instrument of terror and attrition.

Symbolic Role

On top of its tactical successes, U-47 soon became a propaganda weapon for the Nazis. Prien's men received decorations commensurate to his own for their role in the Scapa Flow raid, and Prien himself was feted as a hero. The U-boat’s achievements were even employed as an image to project German naval strength, in the face of the Royal Navy’s superiority. But the high cost of the U-boat war — only 30 per cent of the 39,000 U-boat crewmen survived the war — suggested the considerable danger of the missions that U-47 undertook, and the boat itself disappeared without trace in March 1941, lost with all hands.

Key Roles in Battles

First Patrol (August–September 1939)

U-47 commenced its first war patrol on August 19, 1939, before the war began, and was thus in place to immediately engage the enemy upon the commencement of hostilities. Serving in the Bay of Biscay, U-47 torpedoed its first three ships on 5 September (SS Bosnia), 6 September (SS Rio Claro), and 7 September (SS Gartavon), all with a combined 14,777 GRT. These early successes reflected U-47's effective application of force against merchant shipping, following the Submarine Protocol by helping survivors, such as in the Bosnia sinking when Prien had helped the crew. This patrol set the standard for U-47's activities in adisrupting Allied merchant seamen.

Scapa Flow Raid (October 1939)

U-47's most famous mission came during its second patrol, which began on October 8, 1939. Prien’s mission was to get inside Scapa Flow, the Royal Navy’s main base in the Orkney Islands, and deal a blow to British pride. On 14 October, passing through the narrow channels with the help of the Aurora Borealis the U-47 made her way past the defences into the anchorage. After sighting the battleship HMS Royal Oak, Prien released a salvo of torpedoes at 01:04, which resulted in superficial damage. A second salvo hit Royal Oak after it was re-armed, which resulted in severe flooding. The battleship went down in 15 minutes, losing 835 of its 1,234 crew, including Rear Admiral H.E.C. Blagrove.

The British were stunned by the raid, as they considered Scapa Flow impregnable. This resulted in a strengthening of the defences and a refocusing of the Home Fleet, and indirectly contributed to later losses when German mines laid by the battleship Tirpitz damaged the ships HMS Nelson and HMS Belfast late in the war. Prien’s men received Iron Crosses, but the mission in general, and U-47 specifically, became a by-word for a bold and successful weapon.

Battle of the Atlantic (1940–1941)

U-47 was involved in the Battle of the Atlantic, the longest continuous military campaign of World War II, which sought to block Britain’s lifeline to the rest of the world. Dönitz’ wolfpack strategy, in which U-boats were pitted together, was most heavily demonstrated in the sixth voyage (June–July 1940) of U-47. Based in the south of Ireland as a member of Wolfpack Prien, U-47 destroyed eight ships, such as SS Balmoralwood (June 14), SS San Fernando (June 21) and SS Arandora Star (July 2), with considerable tonnage. This patrol which lasted for 34 days demonstrated U-47’s potential to cause mayhem amongst convoys similar to HX 47.

But not all patrols were locate obvious. U-47 missed or failed to hit HMS Warspite with one torpedo that same month (fifth patrol) and was narrowly missed by depth charges from escorting destroyers. U-Boat Patrol This was the first patrol for U-47 where no ships were sunk, evidence of the increasing success of Allied anti-submarine measures.

U-47' s subsequent patrols also focused on merchant convoys, and it found moderate success in 1940, sinking SS Ville de Mons (2 September) and SS Titan (4 September) on its seventh patrol. By early 1941, Allied responses — including enhanced sonar, air patrols and convoy tactics — were increasing the danger of U-boat operations. The U-47 last set out on patrol in February 1941 hunting convoys in the North Atlantic. On 7 March 1941, U-47 disappeared, presumably sunk by the British destroyers HMS Wolverine and HMS Verity, although some believe it may have been the victim of a circling torpedo or a technical failure. But all 45 crew members aboard, and Prien, were never heard from again, and its fate remains unknown.

Challenges and Limitations

For all of its triumphs, U-47 also endured its share of hard times. As the war expanded and required longer patrols, however, the Type VIIB’s limited mine and torpedo load became a disadvantage. Early in the war faulty torpedoes, which included those with faulty magnetic exploders, marred attacks, like that suffered in the opening salvo of Royal Oak. The Mark 6 exploder, developed from German and British designs, often detonated prematurely or failed to explode at all, and would not be effectively corrected until 1943. Furthermore, improved Allied anti-submarine technologies—HF-DF (high-frequency direction finding), Hedgehog mortars and air patrols—gradually lessened U-47’s efficiency over time.

Life aboard U-47 was arduous. Crews battled for weeks with no sun, always on guard and the constant torment of the threat of depth charges. Harald Busch’s accounts of life on the U-boat reveal monotonous, cold, and dangerous conditions, with technicians hardly ever showing face on the bridge and the crew dealing with “flight alarms, submarine traps, [and] pursuing destroyers.” U-47’s high loss rate—only 15 of the 44 men who crewed Scapa Flow returned from the war—emphasized the attrition that was taking place within the ranks of the submarine service.

Legacy and Impact

While its career was brief, U-47 made a lasting impact. Its sinking of HMS Royal Oak was a propaganda coup as well as a tactical surprise that lead to the Royal Navy re-evaluating its defenses. The U-boat’s contribution to the Battle of the Atlantic underscored the danger the Dönitz submarine fleet posed: by the end of the war it had accounted for more than 11 million tons of Allied shipping. The U-47’s triumph prompted a huge expansion of the Kriegsmarine’s U-boat program, and 709 Type VIIs were ordered by 1945. But the staggering loss rate—711 U-boats destroyed, 27,490 crewmen killed—illustrated the inefficiency of this approach.

Itself is one of the naval history’s great heroes.” The raid on Scapa Flow is analysed as a masterclass in submarine tactics, and its execution is a potent example of the strategic significance of the Battle of the Atlantic. If Britain’s supply lines had been cut, the Allies ability to invade, as they did on D-Day, would have been put at risk. 51) The loss of U-47 in 1941 closed the door to an incredible chapter, one that lives on when one talks about naval warfare and German military thinking.

Final Thoughts

U-47: The U-Boat that Torpedoed a Hollywood Movie Hero As a technological phenomenon, the U-47 was the epitome of Kriegsmarine aspirations to challenge the allies on their own terms, and the rest of the world admired and feared the U boat force. Its Type VIIB variant was the perfect blend of speed, armament and stealth suitable for commerce raiding in dangerous seas and conditions. With Günther Prien at the helm, U-47 performed spectacular acts, from the audacious Scapa Flow raid to its relentless assaults on Atlantic convoys. Its career was tragically brief, however, as U-47’s effect on the naval side of World War II was significant, demonstrating both the promise and the peril of U-boat warfare. Its history is a testament to the bravery, resourcefulness, and sacrifice of its crew.