
German submarine U-40 was a Type IXA U-boat of Nazi Germany's Kriegsmarine that operated during World War II.

The German submarine U-41 was a Type IXA U-boat of Nazi Germany's Kriegsmarine that operated during World War II. She conducted three war patrols during her short career, two as part of the 6th U-boat Flotilla and one as part of the 2nd flotilla. U-41 also sank five enemy vessels for a total of 22,815 gross register tons (GRT); captured two more for a total of 2,073 GRT and damaged one other of 8,096 GRT.

German submarine U-42 was a Type IXA U-boat of Nazi Germany's Kriegsmarine that operated during World War II.

German submarine U-43 was a Type IXA U-boat of Nazi Germany's Kriegsmarine during World War II. The keel for U-43 was laid down in August 1938 at Bremen; she was launched in May 1939 and commissioned in August.

German submarine U-44 was a Type IXA U-boat of Nazi Germany's Kriegsmarine that operated during World War II. She was ordered in November 1936 and laid down in September 1938 in Bremen. She was launched in August 1939 and commissioned in November.

German submarine U-48 was a Type VIIB U-boat of Nazi Germany's Kriegsmarine during World War II, and the most successful that was commissioned. During her two years of active service, U-48 sank 55 ships for a total of 321,000 tons; she also damaged two more for a total of 12,000 tons over twelve war patrols conducted during the opening stages of the Battle of the Atlantic.

German submarine U-49 was a Type VIIB U-boat of Nazi Germany's Kriegsmarine during World War II. She was ordered on 21 November 1936 and laid down on 15 September 1938 at the yards of Friedrich Krupp Germaniawerft AG in Kiel as yard number 584. Launched on 24 June 1939, she was commissioned on 12 August and assigned to the 7th U-Boat Flotilla under the command of Kurt von Goßler.

German submarine U-50 was a Type VIIB U-boat of Nazi Germany's Kriegsmarine during World War II. Ordered on 21 November 1936, she was laid down as yard number 585 at the yards of Friedrich Krupp Germaniawerft AG in Kiel on 3 November 1938. She was launched on 1 November 1939 and commissioned on 12 December 1939 by Kapitänleutnant (Kptlt.) Max-Hermann Bauer, who was the sole commander of the boat. In her short career she conducted only two patrols, both as part of the 7th U-boat Flotilla. In this time she succeeded in sinking four ships, totalling 16,089 gross register tons (GRT).

German submarine U-52 was a type VIIB U-boat of Nazi Germany's Kriegsmarine during World War II. She was initially ordered on 15 May 1937, in violation of the terms of the Treaty of Versailles, and laid down on 9 March 1938, at the yards of Friedrich Krupp Germaniawerft AG in Kiel as yard number 587. Launched on 21 December 1938, she was commissioned on 4 February 1939, under the command of Kapitänleutnant (Kptlt.) Wolfgang Barten.

German submarine U-53 was a Type VIIB U-boat of Nazi Germany's Kriegsmarine during World War II. She was laid down on 13 March 1937 at Friedrich Krupp Germaniawerft in Kiel and went into service on 24 June 1939 under the command of Oberleutnant zur See (Oblt.z.S.) Dietrich Knorr.

German submarine U-54 was a Type VIIB U-boat of Nazi Germany's Kriegsmarine during World War II.

German submarine U-55 was a Type VIIB U-boat of Nazi Germany's Kriegsmarine during World War II. She was ordered on 16 July 1937 and laid down on 2 November 1938 at Friedrich Krupp Germaniawerft in Kiel as yard number 590. Launched on 19 October 1939, she went into service on 21 November 1939 under the command of Kapitänleutnant (Kptlt.) Werner Heidel.