On 13 January 1942 HMS Rosemonde (T/Lt Kristian Galteland, RNR) left Milford Haven en route to Gibraltar together with the minesweeping trawlers HMS Rosalind (T 135) (Skr E.G. Littler, RNR) and HMS Lord Grey (FY 1593) (T/Lt R.M. Bell, RNR), but lost them in stormy weather on 15 January. While the other trawlers arrived at Gibraltar on 22 January, the Admiralty reported HMS Rosemonde as missing and considered lost after the limit of her endurance was reached on 27 January.

At about 23.00 hours on 19 January U-581 attacked what was believed to be a British corvette of some 800 tons steering towards Gibraltar during an extremely dark night with limited visibility due to rain about 400 miles east of the Azores. A first torpedo fired from about 600 yards missed, but then one of spread of two torpedoes struck the vessel amidships and caused it to break in two and sink within one minute, followed by an underwater explosion presumably caused by depth charges. The U-boat searched the vicinity of the sinking for some considerable period, but found no survivors or wreckage. It is very likely that HMS Rosemonde was sunk in this attack.