U-boat Operations

Minelaying patrols

During the war German U-boats planted over 100 small minefields. The Battleship HMS Nelson (28) was hit by a mine and seriously damaged on 4 Dec laid by U-31 on 27 Oct 1939. Nelson was badly damaged and under repairs until June 1940. The light cruiser HMS Belfast (35) was damaged on 21 Nov 1939 by mine laid by U-21 on 4 Nov 1939. HMS Belfast was so badly damaged she was rebuilt until Dec 1942.

Most successful Minelaying operations

U-31Kptlt. Johannes Habekost334,11021 Oct 193931 Oct 1939
U-30Kptlt. Fritz-Julius Lemp633,18223 Dec 193917 Jan 1940
U-701Kptlt. Horst Degen531,60720 May 19427 Jul 1942
U-118KrvKpt. Werner Czygan626,93425 Jan 194326 Feb 1943
U-13Kptlt. Karl Daublebsky von Eichhain322,2032 Sep 19396 Sep 1939
U-32Kptlt. Paul Büchel217,5255 Sep 193930 Sep 1939
U-26Kptlt. Klaus Ewerth317,41429 Aug 193926 Sep 1939
U-561Kptlt. Robert Bartels315,7974 Apr 19425 May 1942
U-117KrvKpt. Hans-Werner Neumann214,26931 Mar 194313 May 1943
U-21Kptlt. Fritz Frauenheim213,76622 Oct 19398 Nov 1939

This table shows ships sunk or damaged by mines during each patrol.

Allied tonnage sunk by U-boats mines

YearShips sunkShips damagedOperationsU-boats
19392775,420 GRT678,311 GRT2319
19401781,430 GRT213,959 GRT1110
194112,879 GRT00 GRT21
1942924,140 GRT728,334 GRT2217
19431748,772 GRT641,051 GRT3622
194421,682 GRT17,177 GRT1611
19451200 GRT00 GRT22
74234,523 GRT22168,832 GRT112

During the war 96 ships of 403,355 GRT were hit by mines laid by German U-boats.

Map of ships hit by U-boat mines

Please note that we only show the locations of ship losses where we have accurate position for (96 ships).


1939. 1940. 1941. 1942. 1943. 1944. 1945.

Click on any marker to see the detail on mine hit. Left double-click to zoom-in. Right double-click to zoom-out.

U-boat Operations