The U-505 is a German Type IXC U-boat famous for being captured by the United States Navy during World War II.

This capture stands as a monumental event due to the rarity of seizing an enemy vessel at sea, especially a fully operational war submarine like the U-505.

She is now preserved as a museum exhibit at the Museum of Science and Industry in Chicago.

Design of the U-505

The U-505, a Type IXC U-boat, was a remarkable feat of engineering and a testament to the advanced submarine technology of its time.

Its construction at the Deutsche Werft shipyard in Hamburg, Germany, was part of Germany’s ambitious plan to dominate underwater warfare.

The keel laying on June 12, 1940, marked the beginning of a meticulous build process that culminated in its launch on May 25, 1941.

This class of U-boat was designed with a strategic blend of range, speed, and firepower, making it a formidable opponent in the vast expanses of the Atlantic Ocean during World War II.

The U-505 measured 252 feet in length, which is about the length of a soccer field, giving it enough space to house its crew and equipment while remaining stealthy and maneuverable.

Its beam was 22 feet, and it had a draft of 15 feet 3 inches, dimensions that were optimized for both surface travel and submerged operations.

The displacement of the U-505 was approximately 1,120 tons when surfaced and 1,232 tons while submerged, reflecting its robust construction that could withstand the pressures of deep-sea dives.

Powered by two MAN M 9 V 40/46 supercharged four-stroke, nine-cylinder diesel engines, the U-505 could reach speeds of up to 18.3 knots (about 21 miles per hour) when surfaced.

This was relatively fast for submarines of that era, enabling the U-505 to outrun many of the merchant ships it preyed upon.

For submerged operations, it relied on two Siemens-Schuckert 2 GU 345/34 double-acting electric motors.

These electric motors allowed the submarine to move quietly and evade detection, reaching speeds of up to 7.3 knots (approximately 8.4 miles per hour) while underwater.

The submarine’s range was equally impressive, capable of traveling up to 13,450 nautical miles at 10 knots while surfaced, thanks to its fuel capacity and efficient design.

U-505 seen here shortly after her capture. The men on her bow are a boarding party from USS Pillsbury.

The U-505 was armed with a formidable array of weapons designed for both offensive operations against enemy shipping and defensive actions against pursuing naval vessels. It had six torpedo tubes in total; four located at the bow and two at the stern.

With these, the U-505 could launch a salvo of torpedoes before submerging to avoid counterattack. The submarine carried 22 torpedoes, allowing it multiple engagements before needing to resupply.

In addition to its torpedoes, the U-505 was equipped with a 105mm deck gun, a feature common among U-boats for engaging unarmed or lightly armed ships and for finishing off damaged enemies.

This deck gun was complemented by anti-aircraft guns for defense against air attacks, highlighting the multifaceted nature of submarine warfare where threats could come from above or below the water.

The U-505 incorporated several technological innovations that enhanced its operational effectiveness.

It featured a sophisticated hydrophone system for detecting enemy ships and submarines by sound, an essential tool in the vast, visually obstructed oceanic theaters.

Additionally, it was outfitted with radar detection equipment, enabling it to avoid enemy radar patrols and aircraft.

The submarine’s design also emphasized crew comfort and efficiency, with relatively spacious living quarters and advanced navigation and communication systems for that time.

Service History

Commissioned into the Kriegsmarine on August 26, 1941, under the command of Kapitänleutnant Axel-Olaf Loewe, the U-505 embarked on a series of patrols that would see it engage Allied shipping across the vast expanses of the Atlantic Ocean.

These missions were part of Nazi Germany’s broader strategy to disrupt Allied supply lines and assert naval dominance.

Initially, the U-505 struggled to make a significant impact. Its early patrols were hampered by mechanical issues and the increasingly effective anti-submarine tactics employed by the Allies.

The submarine’s first few missions yielded limited success, as it grappled with the realities of warfare at sea, including treacherous weather conditions and the constant threat of detection by enemy forces.

Despite these early setbacks, the U-505 gradually began to find its footing. By employing stealth and taking advantage of the vastness of the Atlantic, it managed to sink eight ships totaling 44,962 gross register tons (GRT). These successes, however, came at a great cost.

The U-boat fleet was constantly hunted by Allied naval forces, which employed aircraft, depth charges, and improved sonar technology to track and attack German submarines.

The U-505 itself endured several close calls and sustained damage on multiple occasions, highlighting the perilous nature of its missions.

Boarding parties work on the captured U-Boat as a Grumman TBM Avenger flies overhead.

As the war progressed, the tactics of U-505 and the broader U-boat fleet evolved in response to the enhanced anti-submarine measures of the Allies.

The Germans developed wolfpack tactics, where groups of U-boats would coordinate attacks on convoys, attempting to overwhelm the escorts and sink merchant ships.

However, the U-505 often operated alone or in small groups due to the vast areas it patrolled, from the Caribbean to the waters off West Africa.

Behind the technical and strategic aspects of the U-505’s wartime service were the men who crewed it. Life aboard the submarine was challenging and fraught with danger.

The crew faced constant threats from the enemy, as well as the psychological and physical stresses of prolonged submarine operations.

These included cramped living conditions, limited fresh water, and the ever-present fear of a catastrophic end.

Her Eleven Patrols

The U-505 embarked on a total of eleven war patrols during its service in World War II before being captured on the twelfth.

Each mission was underscored by the strategic intent to disrupt Allied shipping and face the formidable challenges of sea warfare and enemy defenses.

Its maiden voyage in August 1941 served primarily as a shakedown cruise in the North Atlantic, allowing the crew to test the submarine’s capabilities and gain operational experience, though it resulted in no enemy engagements.

The U-505’s second patrol, commencing in November 1941 in the Mid-Atlantic, marked its initiation into active combat as it sank its first Allied vessels, establishing the U-boat as a tangible threat.

By the third patrol in early 1942, the U-505 ventured into the Caribbean and Gulf of Mexico, achieving notable success by sinking several ships and demonstrating the extended reach of German U-boats into American maritime zones.

Subsequent patrols saw the U-505 operating off the West African coast and the Mid-Atlantic through 1942 and into 1943, targeting Allied shipping routes and engaging in combat under increasingly challenging conditions, including heightened Allied anti-submarine measures and adverse weather.

Crew members from the USS Guadalcanal work ro remove water from the partially scuttled U-505.

The sixth patrol in the winter of 1942-1943 was particularly marked by these challenges, with no confirmed sinkings, highlighting the difficulties faced by U-boats due to improved Allied defenses and harsh sea conditions.

Mechanical issues began to plague the U-505 by its seventh patrol in the South Atlantic, limiting its effectiveness.

Despite these setbacks, the U-505 continued its efforts to disrupt Allied shipping in the Caribbean, South Atlantic, and off the West African coast over its next few patrols.

The U-boat faced a constant game of cat-and-mouse with Allied convoys and escorts, hampered by technical problems and the ever-present threat of capture or destruction.

The U-505’s operational history culminated in its twelfth patrol off the coast of West Africa in 1944, which ended with its capture by the United States Navy on June 4, 1944.

The Capture of U-505

The capture of the U-505 on June 4, 1944, is a fascinating episode of World War II.

Task Group 22.3, a hunter-killer group led by the escort carrier USS Guadalcanal under the command of Captain Daniel V. Gallery, was on patrol in the Atlantic Ocean, tasked with locating and neutralizing German U-boats.

The group had been meticulously trained and prepared for a mission that would, if successful, provide a significant intelligence coup.

The U.S. Navy had recognized the value of capturing a German U-boat intact to obtain codebooks, Enigma machines, and other cryptographic materials that could turn the tide in the Battle of the Atlantic.

The capture began with the detection of the U-505 through sonar contact.

The USS Chatelain, one of the destroyer escorts in Task Group 22.3, launched a series of depth charge attacks against the submerged U-boat, forcing it to surface. Severely damaged and unable to dive, the U-505 was vulnerable.

Depth charges detonate near the U-505.

Its captain, Oberleutnant zur See Harald Lange, ordered the crew to abandon ship and scuttle the submarine to prevent its capture.

This action was in line with standard German naval practice to ensure that sensitive materials did not fall into enemy hands.

What followed was an extraordinary feat of naval warfare. Recognizing the opportunity to capture the submarine before it sank, Captain Gallery of the USS Guadalcanal ordered a boarding party to secure the U-505.

Lieutenant (Junior Grade) Albert David led the boarding team, which consisted of volunteers who knew well the dangers of boarding a potentially sinking and booby-trapped enemy vessel.

The team raced against time, braving the risk of explosions and the possibility that the submarine could plunge into the depths at any moment.

The boarding party managed to secure the U-505, preventing it from sinking by closing scuttle valves and disarming demolition charges set by the German crew.

They also seized invaluable items, including codebooks, Enigma machines, and other cryptographic materials, which were later used to bolster Allied codebreaking efforts.

The capture of the U-505 was shrouded in secrecy to prevent the Germans from realizing that their naval codes were compromised.

The crew of the U-505 was isolated to maintain the secrecy of the capture, and the event was not immediately disclosed to the public.

The intelligence gained from the U-505 provided critical insights into German naval operations and contributed to the Allies’ advantage in the Battle of the Atlantic.

From War Machine to Museum Exhibit

After the war, the fate of the U-505 was uncertain. Many captured or surrendered enemy vessels were scrapped or used for target practice.

However, the unique historical significance of the U-505, as one of the few U-boats captured by the Allies and a source of invaluable intelligence, prompted a different approach.

It was ultimately decided that the U-505 would be preserved as a museum exhibit, offering the public a rare glimpse into the undersea warfare of World War II and the intricate technology of German U-boats.

U-505 outside the museum in 1956.

The U-505 found its final resting place at the Museum of Science and Industry in Chicago, Illinois. This was largely thanks to the efforts of Captain Daniel V.

Gallery, who played a pivotal role in the submarine’s capture and later campaigned for its preservation and educational use.

In 1954, the submarine was officially donated to the museum. Transporting the massive U-505 to its new home was an engineering feat in itself; it involved a complex overland journey through Chicago’s streets, drawing widespread public attention and fascination.

U-505 where she now lives in the Museum of Science and Industry, Chicago. Image by aaronx CC BY 2.0

The process of restoring and preparing the U-505 for display was extensive.

The goal was not only to preserve the submarine physically but also to accurately represent its history and the experiences of those who served on similar vessels.

The exhibit opened to the public in September 1954, offering an immersive experience that includes walking through the submarine’s interior.

Visitors can see the cramped quarters, machinery, and armaments, gaining insight into the life of a submariner during World War II.