Convoy JW 51B Convoy JW 51B was an Arctic convoy sent from United Kingdom by the Western Allies to aid the Soviet Union during World War II . It sailed in late December 1942 , reaching the Soviet northern ports in early January 1943 . JW 51B came under attack by German surface units , engaged in Operation " Regenbogen " , on 31 December . In the clash that ensued , one defending minesweeper and one attacking destroyer were sunk with all hands and a defending destroyer was sunk ; no ships were lost from the convoy . This engagement became known as the Battle of the Barents Sea . Forces . JW 51A consisted of 15 merchant ships which departed from Loch Ewe on 22 December 1942 . Close escort was provided by the minesweeper " Bramble " , two corvette s and two armed trawlers . These were supported by six Home Fleet destroyers led by " Onslow " ( Capt R . St . V . Sherbrooke commanding ) . The convoy was also accompanied initially by a local escort group from Britain , and was joined later by a local escort group from Murmansk . A cruiser cover force comprising " Jamaica " and " Sheffield " , and two destroyers , was also at sea , out of Kola Inlet , to guard against attack by surface units , while distant cover was provided by a Heavy Cover Force from Iceland comprising the battleship " Anson " , the cruiser and five destroyers . JW 51B was opposed by a force of four U - boat s in a patrol line in the Norwegian Sea , and the aircraft of Luftflotte V based in Norway . A surface force comprising the heavy cruisers " Hipper " , " Lützow " and six destroyers was also available , stationed at Altenfjord . Action . JW 51B departed Loch Ewe on 22 December 1942 , accompanied by its local escort , of four destroyers , and its close escort . Three days later , on 25 December , it was joined by the ocean escort , while the local escort departed . On 27 December JW 51B ran into a gale , which scattered the convoy over the next two days into several groups across a wide area . One ship , " Dover Hill " had been forced to return with weather damage , while five ships and two escorts had become separated . Three of the ships rejoined on 30 December , but " Chester Valley " , in company with the armed trawler " Vizalma " , and another , with the destroyer " Oribi " , remained separated . During the 30th also , " Bramble " detached from the main body of the convoy to search for the stragglers . On 24 December the convoy had been sighted by a patrolling aircraft , but was lost later during the storm . However on 30 December it was found again by " U - 354 " , and Operation " Regenbogen " was put into effect . On 31 December the German ships , in two sections , met the ocean escort of JW 51B , and after a sharp engagement , which left the minesweeper " Bramble " , destroyer " Achates " sinking , and another , " Onslow " , damaged , the attacking force was driven off . One German destroyer , " Eckholdt " was sunk , and a cruiser , " Hipper " , damaged . No further attacks developed , and on 1 January 1943 " Vizalma " and her charge rejoined the convoy . On 2 January JW 51B was met by its eastern local escort , two minesweepers from Murmansk . On 3 January the main body arrived in Kola Inlet , joined the following day by " Oribi " and her charge . Conclusion . The 15 ships of JW 51B arrived at Murmansk without loss , though one had been damaged . Despite the loss of two warships , JW 51B was a success , and the failure of the German surface force to mount an effective assault on the convoy caused a loss of confidence by Hitler in the German Navy and its commander , Admiral Erich Raeder , which eventually culminated in his resignation . Thereafter , the main threat to the Allied convoy system was from the U - boats . Ships involved . Allied ships . Merchant ships Close escort Ocean escort Cruiser cover force Distant cover force Axis ships . U - boat force Surface force