Convoy SC 143
SC 143 was a North Atlantic convoy of the SC series which ran during the battle of the Atlantic in World War II. It was the second battle in the "Kriegsmarine"s autumn offensive in the North Atlantic. Background. Following the attack on convoys ONS 18 and ON 202 by the wolfpack "Leuthen", U-boat Control ("Befehlshaber der Unterseeboote" (BdU) was convinced of success and eager to continue the offensive. Accordingly, they re-organized the boats then in the North Atlantic into a new patrol line, the 12 remaining "Leuthen" boats being joined by 9 newcomers, from bases  in France and Germany. Code-named "Rossbach", the group was stationed at the western edge of the Greenland Air Gap to intercept the expected east-bound convoys, carrying materiel for the invasion of Europe. For their part, the Allies were also encouraged by the outcome of the battle for ONS 18/ON 202, and were keen to seek battle with group "Rossbach". While forming, "Rossbach" came under attack by air patrols; four boats were destroyed, and another four were damaged and forced to return to base. Three others were damaged, but were able to continue operations, while a further two  boats arrived from base as re-inforcement. Protagonists. SC 143 left Halifax on 28 September 1943 bound for Liverpool It was composed of 39 ships and was escorted by C-2 escort group comprising the destroyer , frigate "Duckworth" and 5 corvettes. Also accompanying the convoy was the MAC carrier . By 6 October "Rossbach", comprising fourteen U-boats at this point, was deployed to intercept the expected west-bound convoys, HX 259 and SC 143. Western Approaches Command became aware of "Rossbach"s position via intelligence, principally Enigma decrypts, but decided to engage the wolfpack and force a battle. Diverting HX 259 to  the south, SC 143 was reinforced with 10th Support Group, of four destroyers, "Musketeer"," Oribi", "Orkan" and "Orwell", and allowed to continue towards "Rossbach" as bait. Action. SC 143 was sighted on 8 October by "U-731", which was returning to base following an air attack; she sent a sighting report, and throughout the day the "Rossbach" boats converged on the position. Seven boats had gathered by evening, and at nightfall mounted their attack. During the night of 8/9 October the seven "Rossbach" boats were able to attack; During the day the convoys air cover was able to mount several successful  attacks; three U-boats were attacked by aircraft during the day. Two other boats were damaged in air attacks and forced to return to base; Following this the attack was discontinued by BdU and "Rossbach", now reduced to six boats, was disbanded. SC 143 continued its voyage, and arrived without further loss at Liverpool on 12 October 1943. Conclusion. Undeterred by the poor result of this attack, and the losses suffered by "Rossbach", BdU wished to press on with the offensive; the remaining "Rossbach" boats were reinforced to form a new group code-named "Schlieffen". Tables. Allied ships sunk Allied  warships sunk Axis submarines destroyed