The Best Ww2 Boats: A Historical Overview

World War II saw the extensive use of submarines by both the Allied and Axis powers. The German Navy used its U-boat fleet to attempt to cut off Great Britain's supply lines, while the US Navy carried out a submarine campaign against Japan with the same objective. Both sides practised unrestricted submarine warfare, meaning submarines would torpedo enemy ships without warning. German U-boats were predominantly used in the Atlantic, while American submarines were primarily used in the Pacific Ocean. The US submarines were responsible for sinking 540,192 tons or 30% of the Japanese Navy and 4,779,902 tons of shipping, or 54.6% of all Japanese shipping in the Pacific Theatre. German U-boats, on the other hand, destroyed 14.1 million tons of Allied shipping, nearly 70% of all Allied losses across all theatres of the war.

German U-boats vs. American submarines

German U-boats and American submarines were designed with different strategic goals in mind. The U-boats were designed for commerce raiding and were expected to operate mainly in the Western Approaches to the UK. In contrast, American submarines like the Gato-class were designed to operate in the Pacific and had the size and range to match. They also had a larger number of torpedo tubes to take on enemy capital ships before escaping.

German U-boats had better dive performance, with a test depth of 700+ feet compared to 300 feet for the Gato-class and 400 feet for the Balao-class. This gave them a better chance of evading detection and attacks. However, U.S. submarines were more advanced in terms of technology, with thermometers and bathythermographs that allowed them to exploit thermal layers.

The U.S. Navy's interwar development of the fleet submarine proved crucial. By the start of World War II, they had versatile "fleet submarines" that outperformed their German counterparts. U.S. submarines could go faster and farther, carry more weapons, and submerge four times faster than German U-boats.

During World War II, 263 U.S. submarines undertook war patrols, claiming 1,392 ships and 5,583,400 tons. They were responsible for sinking 30% of the Japanese Navy and 54.6% of Japanese shipping in the Pacific Theater. The success of U.S. submarines against Japanese shipping was a decisive factor in the collapse of the Japanese economy.

While it is challenging to declare a "best" submarine, the overall advantage lies with the American submarines due to their technological superiority, strategic versatility, and significant contributions to the war effort.

The role of submarines in WWII

Submarines played a significant role during World War II, particularly in the Pacific Ocean, where American submarines were primarily deployed. The U.S. Navy's strategic planning and ship design were influenced by the vastness of the Pacific and the long distances between supply points. Submarines evolved to meet the need for speed and stealth, with improved fuel storage and equipment to produce fresh water and store food for extended periods.

American submarines, such as the Gato-class and Balao-class, were instrumental in attacking enemy ships, disrupting supply lines, and destroying the Japanese merchant marine and its ability to supply food, fuel, and industrial resources for the war effort. They were also involved in humanitarian roles, rescuing downed pilots. The success of American submarines came at a high cost, with 52 submarines and 3,506 officers and enlisted men lost during the war.

German U-boats, on the other hand, posed a significant threat to the Allied Forces in the Atlantic. Germany built 1,162 U-boats during the war, and they were known for their larger hulls, advanced features, and various types. The Treaty of Versailles had initially prevented Germany from having U-boats, but Hitler repudiated the treaty and regained the right to build them in 1935.

Japanese submarines also played a role, although they were not as successful as the Germans. They had a wide variety of submarines, including the large I-400 class and the "midget submarine." Despite their efforts, the Japanese sank about 1 million tons of Allied merchant ships, in comparison to the Germans' 14 million tons and the Americans' nearly 5 million tons.

Submarine technology

German submarines, or unterwasser boats (U-boats), were a formidable force during World War II. Their primary objective was to target and destroy merchant vessels supplying Allied forces to disrupt their war efforts. U-boats were often aided by intelligence reports detailing the location, speed, and destination of these vessels. They operated in "wolf packs", hunting in groups in the North Atlantic waters, or alone in regions where packs were impractical.

U-boats were equipped with deck guns and torpedoes, allowing them to attack from the surface or underwater. They would sometimes track enemy vessels for days before calling in reinforcements for a coordinated attack. After an attack, the crew might assess the damage inflicted before submerging to avoid counter-attacks. The success of U-boat missions was measured by the amount of enemy tonnage sent to the ocean floor.

One notable U-boat was the U-576, commanded by Kapitӓnleutnant Hans-Dieter Heinicke. Launched in 1941, the U-576 and its 45-man crew conducted four patrols as part of the seventh U-boat flotilla based in St. Nazaire, France. During its third patrol in February 1942, it sank its first ship, the 6,900-ton unescorted British freighter Empire Spring, 50 miles from Sable Island. On its fourth patrol, it sank two more ships: the 5,000-ton American merchant vessel Pipestone County and the 1,300-ton Norwegian freighter Taborfell.

U-boat technology varied during World War II, with some boats being relatively simple and unchanged from World War I, while others were highly advanced, such as the Elektro boats of types XXI and XXIII. The challenges and monotony of life aboard a U-boat are well documented, with crew members enduring cramped conditions, monotonous work, and the constant threat of enemy attacks. Despite this, they took pride in their boats and their role in the war effort.

Submarine warfare tactics

U-boat Tactics in World War II

The German U-boat technology at the start of World War II was far superior to that of the Allies. However, as the war progressed, the Allies improved their anti-submarine weaponry, and the Germans had to adapt their U-boat tactics.

U-boats were used in a variety of roles, from coastal patrolling to the combined actions of convoy-hunting 'wolf packs'. The wolf pack tactic was a primary strategy used by U-boats in World War II, which involved the following steps:

• A number of U-boats were dispersed across the possible paths of a convoy.
• Once a boat sighted a convoy, it would signal its course, speed, and composition to the German Naval Command.
• The U-boat would continue to shadow the convoy, reporting any changes in course.
• The rest of the pack would then move towards the first boat's position.
• At nightfall, the pack would coordinate a surface attack.
• At dawn, the pack would withdraw, leaving a single boat to shadow the convoy, and they would resume the attack at dusk.

U-boats also employed deck-gun and torpedo attacks, cooperative operations with aircraft, anti-aircraft defence, and the use of tethered unpowered gyrocopters for target spotting.

The cracking of the Enigma code by the Allies significantly hindered the effectiveness of U-boat tactics, and their impact was greatly reduced despite their advanced tactics.

American submarines in World War II

During World War II, submarines comprised less than 2% of the U.S. Navy but sank over 30% of Japan's navy, including eight aircraft carriers. American submarines also sank almost five million tons of shipping, which was over 60% of the Japanese merchant marine, contributing to the strangling of the Japanese economy.

The USS Gato (SS-212), launched on 21 August 1941, was the first of 54 submarines in its class and carried the brunt of the U.S. submarine war in the early stages of World War II. Later, they were joined by the 122 boats of the Balao-class, which had thicker pressure hulls for increased operating depth.

Submarine aces

U-boats, or German submarines, were responsible for the destruction of enemy shipping during both World Wars. In World War II, U-boats were instrumental in the Battle of the Atlantic, attempting to cut off Allied supply convoys.

Otto Kretschmer

Nicknamed "The Tonnage King," Otto Kretschmer was the most successful U-boat commander during World War II in terms of tonnage sunk. In just 18 months, he sank 47 merchant ships totalling 313,611 tons before being captured in March 1941. Kretschmer was awarded the Knight's Cross, Oak Leaves, and Swords for his achievements.

Wolfgang Lüth

Wolfgang Lüth commanded five U-boats during the war and sank 46 merchant ships totalling 225,204 tons. He received numerous honours, including the Knight's Cross, Oak Leaves, Swords, and Diamonds. Tragically, Lüth was mistakenly shot and killed by a German sentry in May 1945.

Erich Topp

Ranking third among U-boat aces, Erich Topp was in command of U-57 and U-552, sinking 35 ships with a total tonnage of 192,611. After the war, Topp served in Washington, D.C. as NATO's Military Committee Chief of Staff and played a significant role in rebuilding the German navy.

Günther Prien

Günther Prien is famous for his daring infiltration of the British Home Fleet's base at Scapa Flow in 1939, where he sank the battleship HMS Royal Oak. For this feat, he was awarded the Knight's Cross and became the first U-boat commander to receive this honour. Prien sank a total of 30 ships totalling 162,769 tons before going missing in March 1941.

Herbert Schultze

Herbert Schultze, commander of U-48, is known for his bold radio message to Winston Churchill after sinking the British freighter Firby in September 1939. In total, he sank 26 ships with a tonnage of 169,709. Schultze received the Knight's Cross with Oak Leaves and was famous in Germany, Britain, and America.

Heinrich Lehmann-Willenbrock

A highly decorated U-boat commander, Heinrich Lehmann-Willenbrock spent the entirety of the war fighting on U-boats. He is best known for commanding U-96, which was featured in the book and film "Das Boot." Lehmann-Willenbrock sank 24 ships totalling 179,125 tons and received numerous medals for his service.

Georg Lassen

With 26 ships sunk and a total tonnage of 156,082, Georg Lassen concludes our list of U-boat aces. He averaged 39,020 tons per patrol and was awarded the Knight's Cross of the Iron Cross. After a prolific career, Lassen began commanding Pretoria, a hospital ship, in April 1945.

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