| WolfpackBorkum | |
|---|---|
| Active | 18 December 1943 – 3 January 1944 |
| Country |  Nazi Germany |
| Branch | Kriegsmarine |
| Size | 17 submarines |
| Commanders | |
| Notable commanders | Karl-Heinz Marbach Heinrich Schroeteler |
Borkum was awolf pack of GermanU-boats that operated during thebattle of the Atlantic inWorld War II.
Borkum was formed in December 1943 off the coast of Portugal, to intercept convoys sailing to and fromGibraltar,Mediterranean andSouth Atlantic. It was composed of U-boats from the disbanded patrol groupWeddigen, with reinforcements from bases in occupied France.
Borkum was first detailed to assist the passage ofblockade runnersOsorno andAlsterufer which were returning to base. A surface force was also involved in this operation, code-namedBernau. Allied intelligence was aware of this and deployed forces against them.[1] In the ensuing actionsBorkum boatsU-305 andU-415 attacked escort carrierCard, without success, while two destroyers were sunk;Leary byU-275 andHurricane byU-415.U-645 was destroyed by destroyerSchenck[2] and theBernau force lost a destroyer and two torpedo boats. The blockade runners were also lost. TheBorkum boats assisted in picking up survivors.
In January 1944Borkum was reinforced by new U-boats, while a number of the original group returned to base. These came under air attack crossing theBay of Biscay, and three,U-107,U-275 andU-541 were damaged.
The renewedBorkum group, of eight U-boats, was re-organized into three patrol lines to intercept an expected north-bound convoy (MKS 35).However MKS 35 had joined with SL 144 and a US hunter-killer group, centred on the carrierBlock Island, while in the same period a south-bound convoy OS 64/KMS 38 passed through the same area.
In a series of actionsU-305 sank the frigateHMS Tweed, escorting the south-bound convoy, whileU-270 shot down a patrol aircraft, but three U-boats,U-270,U-382 andU-758 were damaged and forced to return.U-953 was subjected to a 13-hour hunt, but eventually escaped.
On 11 January, theBefehlshaber der U-Boote, the supreme commander of the German Navy's U-boat arm, disbandedBorkum;U-953 was sent on a solo patrol in the South Atlantic, which was successful, returning in February 1944.The remaining four boats were sent to reinforce groupRügen in the North Atlantic. None of these U-boats survived.U-377 was lost without a trace,[3] whileU-231 andU-305 were destroyed in transit.[3][4]U-641 joinedRügen but was destroyed in an encounter with the corvetteHMS Violet.[4]
Borkum was named after the island ofBorkum off the GermanNorth Sea coast.