List of all U-boats




Ordered21 Nov 1936
Laid down26 Feb 1937 F. Krupp Germaniawerft AG, Kiel (werk 586)
Launched11 Jun 1938
Commissioned6 Aug 1938Kptlt. Ernst-Günther Heinicke
6 Aug 1938 - Aug, 1939   Ernst-Günter Heinicke
Aug, 1939 - 14 Jan 1940   (boat was vacant)
15 Jan 1940 - 20 Aug 1940  Kptlt. Dietrich Knorr
4 patrols
6 Aug 1938-31 Aug 1939  7. Flottille (active service)
1 Sep 1939-31 Dec 1939  7. Flottille (active service)
1 Jan 1940-20 Aug 1940  7. Flottille (active service)
Successes5 ships sunk, total tonnage 26,296 GRT
1 auxiliary warship sunk, total tonnage 4,724 GRT

Sunk on 20 August 1940 in the Bay of Biscay west of St. Nazaire, in position 47.06N, 04.51W, by a torpedo from the British submarine HMS Cachalot. 43 dead (all hands lost).

Loss position

See the 6 ships hit by U-51 - View the 4 war patrols

Wolfpack operations

U-51 operated with the following Wolfpacks during its career:
   Prien (12 Jun 1940 - 17 Jun 1940)

Attacks on this boat and other events

21 Apr 1940
The French submarine Orphée launched two torpedoes at U-51. Both missed.

1 recorded attack on this boat.

General notes on this boat

29 Jan 1940. On 29 January 1940 U-51 was forced to return to base by technical problems.

19 Apr 1940. The boat attempted to torpedo the French light cruiser Emile Bertin in Norwegian waters, but missed.

Men lost from U-boats

Unlike many other U-boats, which during their service lost men due to accidents and various other causes, U-51 did not suffer any casualties (we know of) until the time of her loss.

U-boat Emblems

We have 1 emblem entry for this boat. See the emblem page for this boat or view emblems individually below.

Atje and Bambo, 2 Dogs

Media links

U-Boat Operations of the Second World War - Vol 1

Wynn, Kenneth

German U-Boat Losses During World War II

Niestle, Axel

Hitler's U-boat War

Blair, Clay


Dickens, Peter and Grove, Eric J.

Submarines versus U-boats

Jones, Geoffrey

There was another U-51 in World War One
That boat was launched from its shipyard on 25 Nov 1915 and commissioned into the Imperial Navy on 24 Feb 1916. The Naval war in WWI was brought to an end with the Armistice signed on 11 Nov, 1918. Read about SM U 51 during WWI.