This was a U-boat wolfpack operation in the Arctic largely against the JW.59 convoy (17 August/6 September 1944).
The wolfpack comprised U-344, U-354, U-363, U-395, U-668, U-703 and U-997, and for the loss of Kapitänleutnant Ulrich Pietsch’s U-344, Oberleutnant Hans-Jürgen Sthamer’s U-354 and Kapitänleutnant Wolfgang Borger’s U-394 sank 14,070 tons of British warships in the form of the escort carrier Nabob, sloop Kite and frigate Bickerton.
It was on 15 August that the JW.59 convoy had departed British waters with 33 laden ships, one rescue vessel and 11 US submarine chasers on Lend-Lease transfer to the Soviet Northern Fleet. Close cover for most of the convoy’s passage was provided by Vice Admiral F. H. G. Dalrymple-Hamilton’s detachment of Admiral Sir Henry Moore’s Home Fleet (escort carriers Vindex and Striker, light cruiser Jamaica, and destroyers Milne, Caprice, Marne, Meteor and Musketeer), and close escort was provided by the 20th and 22nd Escort Groups (destroyers Keppel and Whitehall, sloops Cygnet, Kite, Mermaid and Peacock, frigate Loch Dunvegan, and corvettes Bluebell, Camellia, Charlock, Honeysuckle and Oxlip).
Under the command of Admiral Gordei I. Levchenko, the Soviet transfer force of Ex-British ships which made its northward passage at almost the same time comprised the battleship Arkhangyel’sk (ex-British Royal Sovereign) and the ex-US 'flush-deck' destroyers Zharkiy, Zhivuchiy, Zhguchiy, Zhostkiy, Derzkiy, Doblestnyi, Dostoinyi and Deyatelnyi. This force departed on 17 August and maintained a position to the north of the convoy.
Home Fleet units were operating in two groups at exactly the same time for the ‘Goodwood’ (ii) attacks on the battleship Tirpitz in the Kåfjord: Rear Admiral R. R. McGrigor commanded the fleet carriers Indefatigable, Formidable and Furious, battleship Duke of York, heavy cruisers Berwick and Devonshire, and 14 destroyers including Kempenfelt, Myngs, Vigilant, Zambesi, Canadian Algonquin and Sioux, and Free Norwegian Stord, as well as the escort carriers Trumpeter and Canadian Nabob with Commander D. G. F. W. MacIntyre’s 5th Escort Group (frigates Bickerton, Aylmer, Bligh, Garlies, Keats and Kempthorne).
On 20 August a Junkers Ju 88 reconnaissance bomber from a base in the northern part of German-occupied Norway spotted and reported an Allied naval force operating to the east of Jan Mayen island.
Early on 21 August the JW.59 convoy reached the patrol line of the ‘Trutz’ (ii) wolfpack, currently comprising U-344, U-363, U-394, U-668 and U-997, and U-344 made an unsuccessful attack on the 22nd Escort Group before sinking the sloop Kite. The boat also made a full sighting report, and as a result a patrol line was formed for 22 August using the newly arrived U-354 and U-703 as well as U-365 and U-711 on their arrival from the Kara Sea. On 22 August U-344 was spotted and sunk with rockets by a Fairey Swordfish anti-submarine aeroplane of the FAA’s No. 825 Squadron from Vindex. During the afternoon of 22 August the outbound U-354 met the escort carrier group, which was preparing to refuel the escorts, and torpedoed Nabob and Bickerton: the latter was abandoned and sunk by a torpedo from the frigate Aylmer. A second attempt to attack Nabob was frustrated by Grumman Avenger anti-submarine aircraft which managed to take-off from the flight deck of the listing aircraft carrier. The carrier was taken in tow but was later deemed incapable of economic repair.
Near the convoy, U-363, U-394, U-668, U-703 and U-997 beat off a force of three Swordfish aircraft and several Grumman Wildcat fighters from Vindex and Striker, as a well as a Soviet GST flying boat, but were nonetheless forced to dive and so lost contact with the convoy and its escorts.
On 23 August only U-365, U-394 and U-711 were able to take their places in the planned patrol line of the ‘Trutz’ (ii) wolfpack, all the other boats being too far astern of the convoy. U-394 got a bearing on basis of the escorts’ radio traffic. U-363 and U-703 were driven to submerge the convoy and the other boats astern of it by the combination of air and surface escorts. U-711 launched torpedoes at Arkhangyel’sk and Zharkiy, but the weapons suffered premature detonations. The destroyer Derzkiy attacked a U-boat, but this escaped.
Until 24 August the boats tried but failed to close on the convoy and its escorts, but were denied once more by the strength of the air and sea escorts. U-363, U-668 and U-997 each fired at the escorts but missed, and U-354 was sunk by the sloops Mermaid and Peacock, frigate Loch Dunvegan and the leader of the 20th Escort Group, namely the destroyer Keppel.
On 24 August the convoy escort was boosted in strength by the arrival of a Soviet escort group comprising the flotilla leader Baku and destroyers Gremyashchiy, Gromkiy and Razyaronnyi, two patrol ships, four minesweepers and four submarine chasers.
The convoy reached port on 25 August, so the Germans terminated the operation against it and ordered the relocation of the surviving boats to the Bjørnøya Passage for deployment against the RA.59A convoy, which departed northern Russia on 28 August with nine unladen ships and the forces which had escorted the JW.59 convoy. Neither German air reconnaissance nor the boats of the ‘Trutz’ (ii) wolfpack managed to approach it, and the convoy reached Loch Ewe without loss on 6 September.
On 2 September U-394 was damaged by a Swordfish of the FAA’s No. 825 Squadron from Vindex, and then sunk by the destroyers Keppel and Whitehall, and the sloops Mermaid and Peacock.