This was a U-boat wolfpack operation in the Atlantic against the HX.224 convoy (22 January/3 February 1943).
The wolfpack comprised U-71, U-187, U-257, U-262, U-267, U-333, U-384, U-402, U-404, U-444, U-454, U-456, U-465, U-553, U-572, U-584, U-609, U-614, U-631 and U-632, and for the loss of Korvettenkapitän Karl Thurmann’s U-553 sank three ships (24,823 tons).
The ‘Landsknecht’ wolfpack was created with those U-boats of the former ‘Falke’ (ii) wolfpack that were running short of fuel and therefore unavailable for operations deep into the Atlantic. The wolfpack operated without success in the area to the west of Ireland, and from 28 January most of the U-boats started to return to base, though U-553 was missing from that date for reasons which remain unexplained.
On 1 February, en route to a new formation, U-456 sighted and reported the HX.224 convoy of 58 laden ships bound from New York to Liverpool and supported by Lieutenant Commander D. W. Piers’s Canadian Escort Group C4 (destroyers Restigouche and British Churchill, corvettes Amherst, Brandon, Collingwood, Sherbrooke and British Celandine, and rescue ship Accrington).
Despite a heavy storm, Kapitänleutnant Max-Martin Teichert’s U-456 maintained contact for three days and sank the 7,177-ton US Jeremiah van Rensselaer and 9,456-ton British Inverilen. U-265, U-614, U-257 and Korvettenkapitän Hans Karpf’s U-632 were on patrol in the right area, but only the last was successful, sinking the straggling 8,190-ton British tanker Cordelia, whose garrulous survivors yielded valuable information about the following SC.118 convoy.