A support group consisting of the escort carrier Audacity (Cdr MacKendrick) and the escort destroyers Blankney, Exmoor and Stanley.

In the convoy there is a merchant catapult ship (CAM).

Reinforcements:
U-71 (Korvkpt Flachsenberg), U-125 (Kptlt Folkers), U-567 (Kptlt Endrass) *, U-574 (Oblt Gengelbach ) *, U-751 (Kptlt Bigalk)

* U-boats that fired torpedo or used the deck gun

In the night of Dec 14th U-74, who is on the way to the Mediterranean, sights a small convoy of 4 ships with 4 escorts, from which U-77 sinks and damages one ship.

On the 15th the convoy is too far away to be spotted by the Fw 200's Only on midday of the 16th contact is established. But U-67, U-108 and U-131 who are trying to approach, are driven off. Also during next day U-107, U-108 and U-131 get no chance to launch an attack. U-131 is repeatedly attacked herself by the aircraft of the Audacity, shoots down one aircraft but suffers a lot of damage and is unable to dive when the escort approaches. The boat scuttles herself and the crew is taken prisoner.

U-434 keeps contact during the night of the 17th but in the morning of the 18th she is detected by the escort and sunk. Also 2 Fw 200 planes keeping contact with the convoy are shot down by Martlets of the Audacity. During the day, attacks by U-107 and U-67 are again repulsed by the escorts.

Only towards the morning of the 19th, U-574 has finally success and sinks the HMS Stanley. Cdr Walker orders at once 'Operation Buttercup ': the ships near the site of the torpedoed ship fire snowflakes forcing the U-boat visible on the surface to dive. Once the U-boat is 'in the cellar' it is easier to chase it at night. The Stork damages with depth charges U-574, forcing it make surface. There it is rammed and sunk by the Stork. The Stork and Stanley were the only ships at the rear of the convoy and with the former chasing U-574 and the latter sunk.

U-108 takes the opportunity to attack from the rear and sinks one ship.

In the next days U-107 keeps contact and brings up the other boats, but all approaches are frustrated by the escort and aircraft from the Audacity. But in the night of 21 Dec the boats who have been reinforced by U-71, U-567 and U-751 press home their attacks.

Cdr Walker is informed by the Submarine Tracking Group that at least 6 U-boats are concentrated around the convoy. He orders a diversification act: 4 escorts simulate a battle involving snowflakes and depth charges. In the meantime the convoy will alter sharply course and hopefully the boats will loose track. Unfortunately one of the merchant ships fires in the heat of the act some snowflakes and the whole operation fails.

U-567 locates the convoy and attacks sinking one ship. U-751 attacks at the same time on the other side of the convoy and finds there the lonely Audacity who is operating independently outside the convoy. In 2 approaches the Audacity is sunk by the U-751. U-67 misses the catapult ship. U-567 is sunk with depth charges by the Deptford.

The attacks continue the next day , but the escort is reinforced with the destroyers Vanquisher and Witch and on the 22th U-71 and U-125 are driven of. U-751 on the 23th is the last boat to have contact.

The severe losses sustained in this convoy battle discourage the BdU from organising any other battle until the boats can outnumber the escorts. On the other hand, the very strong escort provided by the British Navy, is only made possible by the Americans, who have taken over escort duties on the North Atlantic routes. After the Japanese attack on Pearl Harbour, most of the American ships are withdrawn into the Pacific. The situation improves even more when the British have to send one of their own escort groups into the Caribbean in order to help the Americans to establish efficient, escorted convoy systems.