This was a U-boat wolfpack operation in the Atlantic against the MKF.3 and HX.217 convoys (30 November/11 December 1942).
The wolfpack comprised U-221, U-373, U-455, U-553, U-569, U-600, U-604, U-609, U-610 and U-615, and for the loss of none of its own number sank three ships (19,092 tons).
It was on 30 November that the ‘Draufgänger’ (i) wolfpack was established to the west of Ireland to operate against the ONS.150 convoy which was believed, on the basis of radio messages intercepted and decrypted by the B-Dienst, to be in the area. The wolfpack located no convoy, however.
On 2 December Kapitänleutnant Horst Höltring’s U-604 sank the 7,057-ton US Coamo of the MKF.3 convoy, while U-435 and U-615 failed in their attacks. The wolfpack was then shifted farther to the north for attacks, from 6 December, on the ONS.150 convoy. Supported by the British Escort Group B4, this convoy was expected according to convoy schedule. In the absence of this convoy, on 7 December the boats were directed to leave their unsuccessful patrol line and tackle the HX.217 convoy.
On 29 November the ‘Panther’ wolfpack had been formed in the central part of the North Atlantic from the newly arrived U-439, U-254, U-758, U-465, U-135, U-211 and U-524 to attack the ONS.148 convoy, which was supported by the British Escort Group B2. The wolfpack headed westward to a location to the north-east of Newfoundland until 4 December, but found no targets. U-524 was carrying a German naval radio intercept and decrypting team, which listened to the convoy’s transmissions on 4 December and made it possible for the wolfpack to be switched to the north-east.
At about mid-day on 6 December boats of the wolfpack sighted the HX.217 convoy of 33 ships supported by Commander R. Heathcote’s British Escort Group B6 with the destroyers Fame and Polish Burza, and corvettes Vervain and Norwegian Eglantine, Potentilla and Rose, together with the rescue ship Perth which was fitted with HF/DF.
The four U-boats approached in the afternoon of 6 December but then lost contact in deteriorating visibility and were distracted by the destroyer Montgomery of the western local escort force, which fired flares off to one flank. During the morning of 7 December U-524 again established contact and vectored in U-254, U-465, U-439 and U-135, but the U-boats were then driven off by the appearance of a Consolidated Liberator long-range maritime patrol bomber of the RAF’s No. 120 Squadron.
During the night of 7/8 December Kapitänleutnant Walter Freiherr von Steinacker’s U-524 sank the 8,194-ton British Empire Spenser and just missed Fame. U-254, U-465, U-623 (arriving with U-611 after refuelling) and U-758 were located by Eglantine, Rose, Burza and Potentilla before reaching any firing position, and were driven off.
On 8 December the boats of the ‘Draufgänger’ (i) wolfpack neared the area after Kapitänleutnant Bernhard Zurmühlen’s U-600 had already sunk an HX.217 straggler, the 6,762-ton US James McKay, on 7 December. On 8 November Kapitänleutnant Nikolaus von Jacobs’s U-611 was attacked and sunk by a Liberator of No. 120 Squadron. In the afternoon of 8 December U-610 and U-553 each established contact, but after missing a destroyer they and three other boats were forced to submerge by the arrival of two Liberator aircraft of No. 120 Squadron. In the evening of 8 December Oberleutnant Hans-Hartwig Trojer’s U-221 accidentally rammed and sank Kapitänleutnant Odo Loewe’s U-254. Two U-boats were driven off by Potentilla and Rose.
During the morning of 9 December U-455 attacked but missed an escort vessel, and Korvettenkapitän Karl Thurmann’s U-553 sank the 5,273-ton British Charles L. D., a straggler from the HX.217 convoy. Two further attacks were frustrated by Eglantine and Potentilla. During 9 December U-553 managed to maintain contact.
In the following night only U-758 was able to attack, but missed Burza. Six other attacks were prevented by Potentilla, Rose, Potentilla again, Vervain, Burza and Rose. Despite the strong Allied air escort, comprising six Lockheed Hudson machines of the RAF’s No. 269 Squadron, Boeing Fortress aircraft of the RAF’s No. 220 Squadron and Consolidated PBY flying boats of the US Navy’s VP-84 squadron, U-628 was able to maintain contact until the night of 11/12 December. U-610, U-615 and U-623 were driven off, however, and U-609 was slightly damaged by Consolidated Catalina of the RAF’s No. 84 Squadron.
Another attempt on the convoy during 11 December was clearly impractical because of the strength of the Allied air escort, and the undertaking was terminated.