'Robbe' (ii) was a U-boat wolfpack operation in the Atlantic against the UC.1, OS.44 and other convoys (16 February/13 March 1943).

The wolfpack comprised U-103, U-107, U-382, U-410, U-437, U-445, U-511 and U-569, and for the loss of none of its own number sank six ships (32,310 tons) and damaged another two ships (16,945 tons) in attacks on the UC.1, KMS.10 and OS.44 convoys.

U-437 left the pack on 20 February to escort the 7,892-ton ex-Norwegian tanker Herborg, which had been captured in June 1942, renamed Hohenfriedberg and was now on her way back from Japan, while U-382 and U-569 departed to reinforce the 'Haudegen' (i) pack in its attack on the UC.1 convoy.

From 16 February U-boat searches for Allied convoys on the route between the eastern USA and Gibraltar were undertake in the area to the south of the Azores islands group by the 'Rochen' wolfpack, and to their north by the 'Robbe' (ii) wolfpack. From From 28 February the 'Robbe' (ii) wolfpack, reduced to U-103, U-107, U-410, U-445 and U-511, operated in the area of the Atlantic to the west of Gibraltar against the KMS.10 convoy of 50 ships supported by Lieutenant Commander A. H. Dobson’s Canadian Escort Group C2 (destroyer St Croix, and corvettes Battleford, Kenogami, Napanee and Shediac) and a Canadian support group (corvettes Baddeck, Prescott and Regina, and minesweepers Fort York, Qualicum and Wedgeport, and also against the XK.2 convoy of 20 ships supported by Lieutenant Command A. H. Davies’s British 38^th Escort Group (corvettes Coreopsis, Anchusa, Columbine and Jonquil, and anti-submarine trawler Loch Askaig) supported by the destroyer Vanoc.

On 1 March Columbine drove off U-445 before the boat could sight the XK.2 convoy, but on 4 March both convoys were sighted and reported by Focke-Wulf Fw 200 Condor long-range maritime reconnaissance bombers, searching on the basis of B-Dienst intelligence, and in air attacks by by Fw 200 and Dornier Do 217 anti-ship bombers of Major Karl Henkelmann’s I/Kampfgeschwader 40 one 4,765-ton ship was damaged. Kapitänleutnant Joachim Berger’s returning U-87 made contact with the KMS.10 convoy, but was sunk by St Croix and Shediac before being able to report the convoy’s presence.

On 5 March Oberleutnant Siegfried Keller’s outbound U-130 made a submerged daylight attack and sank four British ships of the XK.2 convoy, namely the 4,378-ton Empire Tower, 1,574-ton Fidra, 5,108-ton Ger-y-Bryn and 5,299-ton Trefusis.

The KMS.10 convoy, which was being escorted by Consolidated Catalina flying boats of the RAF’s No. 202 Squadron, was located and reported by Fw 200 aircraft, and Grossadmiral Karl Dönitz, now commander-in-chief of the German navy as well as remaining in day-to-day command of the U-boat arm via Konteradmiral Eberhard Godt, the service’s operations chief, ordered five boats from the 'Robbe' (ii) wolfpack to attack. U-107 was forced to submerge by a Catalina, and U-445 did not arrive. This left three boats, of which Oberleutnant Horst-Arno Fenski’s U-410 sank the 7,133-ton British Fort Battle River and damaged the 7,134-ton British Fort Paskoyac before being depth-charged and slightly damaged by Shediac and Catalina flying boats.

On 8 March the Germans discovered, from B-Dienst signals decryption intelligence as well as German agents watching from neutral Spain, that the MKS.9 convoy was departing Gibraltar with 56 ships escorted by the Canadian Escort Group C1, and also learned of the departure of the following MKF.10A convoy of six ships supported by Commander J. W. Farquhar’s 44^th Escort Group (sloops Egret, Erne and Fishguard) and another escort group (frigate Test and destroyers Wheatland, Calpe and Holcombe). U-103, U-107, U-410 and U-445 were instructed to establish a new patrol line, and on 9 March U-107 reported the convoy but then lost contact.

On 12 March the B-Dienst and Fw 200 aircraft located the OS.44 convoy of with 48 ships supported by Commander H. V. King’s 39^th Escort Group (sloops Fleetwood, Rochester and Scarborough, and corvettes Balsam, Coltsfoot, Mignonette and Spirea). During the night of 12/13 March Kapitänleutnant Harald Gelhaus’s U-107 attacked the OS.44 convoy and sank four British ships, namely the 5,442-ton Clan Alpine, 4,592-ton Marcella, 2,352-ton Oporto and 4,990-ton Sembilangan. On 13 March the B-Dienst and Fw 200 aircraft also located the MKS.9 convoy, but the efforts of U-410 and U-445 to make contact failed, and Korvettenkapitän Kurt-Eduard Engelmann’s returning U-163 encountered the escort and was sunk by the corvette Prescott.

When the B-Dienst reported the departure of the MKF.10B convoy of four ships, supported by Commander G. N. Brewer’s Canadian Escort Group C4 (destroyers Restigouche and British Churchill, and corvettes Amherst, Brandon, Collingwood and British Celandine), there were no U-boats available to attempt an interception.