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 German Navy’s (’’Kriegsmarine’’)(KM)’s autumn offensive in the North Atlantic.
Following the attack on convoys ONS.18 and ON 202 by the wolf pack 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 new-comers, 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 war 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; 4 boats were destroyed, and another 4 were damaged and forced to return to base. 3 others were damaged, but were able to continue operations, while a further 2 boats arrived from base as re-inforcement.
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 Icarus, frigate Duckworth and 5 corvettes. Also accompanying the convoy was the MAC carrier Rapana.
By 6 October Rossbach, comprising 14 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 wolf-pack and force a battle. Diverting HX 259 to the south, SC 143 was reinforced with 10th Support Group, of 4 destroyers, Musketeer, Oribi, Orkan and Orwell, and allowed to continue towards Rossbach as bait.
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.
7 boats had gathered by evening, and at nightfall mounted their attack.
During the night of 8/9 October the 7 Rossbach boats were able to attack; U-645 torpedoed and sank Yorkmar, and U-378 hit Orkan which sank with the loss of 157 men. This was the worst naval loss suffered by the Polish navy during the war.
During the day the convoys air cover was able to mount several successful attacks; 3 U-boats were attacked by aircraft during the day. U-419 was attacked and sunk by a Liberator from RAF 86 squadron; U-643 was damaged by 2 other Liberators, from RAF 86 sqdn and RAF 120 sqdn; it was later caught on the surface by another Liberator of RAF 86sqdn and sunk. U-610 was attacked by a Sunderland from RCAF 423 sqdn and sunk.
2 other boats were damaged in air attacks and forced to return to base; U-539 by an unidentified aircraft, and U-762 by a Liberator of RAF 120 sqdn.
Following this the attack was discontinued by BdU and Rossbach, now reduced to 6 boats, was disbanded. SC 143 continued its voyage, and arrived without further loss at Liverpool on 12 October 1943.
Un-deterred 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 re-inforced to form a new group code-named Schlieffen.
Allied ships sunk
|9 Oct 1943||Yorkmar||US||13||5612 GRT||U-645|
Allied warships sunk
|8 Oct 1943||Orkan||Pol||157||destroyer||U-378|
|8 Oct 1943||U-419||VIIC||O/L Glenburg||48||Lib R 86 Sqdn|
|8 Oct||U-643||VIIC||K/L Speidel||30|| Lib R 86 Sqdn|
Lib Z 86 Sqdn
Lib T 120 Sqdn
|8 Oct||U-610||VIIC|| K/L Freyburg|
|51|| Sund J 423 Sqdn|