This was a U-boat wolfpack two-part operation in the Atlantic against sundry HX and OB convoys (11/22 May 1941).
At varying times the U-boats in these first major wolfpack operations were U-43, U-46, U-48, U-66, U-73, U-74, U-75, U-77, U-93, U-94, U-97, U-98, U-101, U-108, U-109, U-110, U-111, U-201, U-204, U-553, U-556, U-557 and U-751, and for the loss of Kapitänleutnant Fritz-Julius Lemp’s U-110 sank 33 ships (191,414 tons) and damaged four ships (33,448 tons) in attacks on the HX.126, HX.128, OB.317, OB.318, OB.322, OB.327, OB.328, OB.329, OB.330 and SC.30 convoys.
Following the operation against the OB.318 convoy, U-93, U-94, U-98 and U-556 were established as the ‘West’ (ii) wolfpack’ to which was added, on 13 May, U-74, U-97, U-109 and U-111. The new wolfpack passaged to its planned operational area to the south-south-east of Cape Farewell, Greenland. As the wolfpack moved to the north-west, on 13 May Kapitänleutnant Robert Gysae’s U-98 sank the 10,529-ton British armed merchant cruiser Salopian, which was part of the SC.30 convoy. Six days later Kapitänleutnant Herbert Kuppisch’s U-94 sighted the HX.126 convoy escorted by the armed merchant cruiser Aurania and submarine Tribune: before losing contact, the U-boat sank the 6,128-ton Norwegian John P. Pedersen and 4,718-ton British Norman Monarch. At about 12.00 on 20 May Kapitänleutnant Herbert Wohlfarth’s U-556 regained contact with the convoy and in two approaches sank the 4,974-ton British Darlington Court and 5,995-ton British Cockaponset, and torpedoed and damaged the 8,470-ton British tanker British Security, which burned for three days before sinking.
By the evening of the same day U-94, U-98 and U-111 had reached the scene, toward morning on 21 May U-93 had also arrived, and on 22 May the German strength had been further increased by the advent of U-46, U-66, U-74, U-94 and U-557. U-74 was depth-charged and damaged, and the U-boats then lost contact with the convoy.
In the period between 1 and 22 May many sinkings were made by the boats of the ‘West’ wolfpack: including attacks on the HX.126 and OB.318 convoys, these sinkings were credited to Kapitänleutnant Udo Heilmann’s U-97 (three ships totalling 17,852 tons), Wohlfarth’s U-556 (five ships totalling 23,557 tons and damage to two ships totalling 18,023 tons), Kuppisch’s U-94 (five ships totalling 31,940 tons), Lemp’s U-110 (two ships totalling 7,585 tons), Oberleutnant Adalbert Schnee’s U-201 (one ship of 5,802 tons and damage to one ship of 5,969 tons), Kapitänleutnant Wilhelm Kleinschmidt’s U-111 (three ships totalling 15,978 tons), Gysae’s U-98 (two ships totalling 15,905 tons), Korvettenkapitän Hans-Georg Fischer’s U-109 (one ship of 7,402 tons), and Kapitänleutnant Claus Korth’s U-93 (one ship of 6,235 tons).
After this, Vizeadmiral Karl Dönitz, the Befehlshaber der Unterseeboote, relocated the ‘West’ (ii) wolfpack, in the form of U-43, U-46, U-93, U-94, U-93 and U-557, to a patrol line over which the battleship Bismarck, retiring toward a base in German-occupied France at the end of her ‘Rheinübung’ sortie into the North Atlantic, was to draw her pursuers on 25 May. Meanwhile U-48, U-73, U-74, U-97, U-98, U-556 and the Italian Barbarigo were stationed in the western part of the Bay of Biscay as a precautionary measure to meet Bismarck.
On 1 June a new ‘West’ (ii) wolfpack was established from the U-boats stationed in the western part of the Atlantic, and initially comprised U-43, U-46, U-66 and U-111, of which the last had replenished on 25/26 May from the tanker Belchen in the Davis Strait, and these were supplemented in the short term, after they too had replenished from Belchen, by U-93 and U-557.
Belchen was sunk by the light cruisers Aurora and Kenya on 3 June while replenishing U-93, which rescued 49 survivors. By 20 June U-48, U-73, U-75, U-77, U-101, U-108, U-204, U-553, U-558 and U-751 had also become part of the ‘West’ (ii) wolfpack. The boats met only independent sailers and convoy stragglers. Oberleutnant Ottokar Arnold Paulssen’s U-557 sank the 7,290-ton British Empire Storm, Kapitänleutnant Engelbert Endrass’s U-46 sank the 5,623-ton British Phidias and damaged the 6,207-ton British Ensis, U-108 sank six ships totalling 24,445 tons, Kapitänleutnant Klaus Scholtz’s U-48 sank the 3,164-ton British Baron Nairn, 4,240-ton Greek Dirphys, 1,992-ton Norwegian Christian Krohg, 3,059-ton Greek Elleniko and 4,362-ton Greek Nikolos Pateras, Kapitänleutnant Helmuth Ringelmann’s U-75 sank the 4,801-ton Dutch Eibergen, Kapitänleutnant Ernst Mengersen’s U-101 sank the 5,271-ton British Trecarrell and 5,270-ton British Trevarrack, Kapitänleutnant Wolfgang Lüth’s U-43 sank the 4,802-ton Dutch Yselhaven and 2,727-ton British Cathrine, Kapitänleutnant Walter Kell’s U-204 sank the 7,866-ton Belgian Mercier, Kapitänleutnant Karl Thurmann’sU-553 sank the 2,355-ton British Susan Maersk and 5,590-ton Norwegian Ranella, Oberleutnant Heinrich Schonder’s U-77 sank the 4,743-ton British Tresillian, 2,379-ton British Arakaka and 4,603-ton Greek Anna Bulgaris, and Kapitänleutnant Gerhard Bigalk’s U-751 sank the 5,370-ton British St Lindsay.
A foray by U-111 into the area of the Belle Isle Strait and as far as Cape Race proved unfruitful as a result of the mist and fog with which the area abounds.