Convoy SC 42

Convoy SC 42 was the 42nd of the numbered series of World War II Slow Convoys of merchant ships from Sydney, Cape Breton Island to Liverpool. SC 42 was attacked over a three night period in September 1941, losing 16 ships sunk and 4 damaged. This was the worst Allied loss following the attack on convoy SC 7 the previous year. Two attacking U boats were destroyed.

Background
Sixty-five ships departed Sydney (Nova Scotia) on 30 August 1941 under local escort, bound for Liverpool. The convoy commodore was Rear Admiral WB Mackenzie in Everleigh. A week later, they were met just east of the Strait of Belle Isle by the Canadian 24th Escort Group consisting of the Canadian River class destroyer Skeena (Lt Cdr JC Hibbard, senior officer) with Flower class corvettes Alberni, Kenogami, and Orillia. Corvettes Chambly and Moosejaw were conducting training exercises in the convoy path at the direction of Commander James D. Prentice, RCN, and were prepared to reinforce the escort as the convoy entered an area where U-boats were known to be waiting.

Ranged against them was the Markgraf wolf pack, a group of 14 U-boats in a patrol line southeast of Greenland.

Action
Early on 9 September U-85 sighted the convoy near Cape Farewell, Greenland and made an unsuccessful torpedo attack. She then commenced shadowing, while other Markgraf boats moved in. The moon rose on the southern side on the convoy that night, and U-432 torpedoed the silhouetted 5229-ton British freighter Muneric. Muneric and her cargo of 7000 tons of iron ore sank rapidly with all 63 of her crew. Kenogami commenced firing on a surfaced U-boat without benefit of star shell or flashless powder, and quickly lost contact as the crew lost their night-vision in the flash of gunfire.

The convoy made two emergency turns over the next half-hour as ships in convoy reported sighting three more surfaced U-boats. Another emergency convoy turn ninety minutes later caught Skeena pursuing a contact at speed. While maneuvering to avoid collision, Skeena passed a surfaced U-boat on a reciprocal course, being fired upon by ships in convoy so closely that Skeena's guns could not be depressed to bear. U-652 torpedoed Baron Pentland and Tahchee during the excitement. The tanker Tahchee was towed back to port by Orillia but the 3410-ton British freighter Baron Pentland sank with 1512 standards of lumber and two of her crew.

Another emergency turn by the convoy brought two hours of suspenseful quiet while Orillia aided Tahchee and searched for survivors astern of the convoy. Then U-432 torpedoed the 3205-ton Dutch freighter Winterswijk and the 1113-ton Norwegian freighter Stargard. The freighter Regin stopped to rescue Starguard's survivors and opened fire on a surfaced U-boat. While Skeena and Kenogami searched for U-boats around stricken Winterswijk and Stargard, U-81 torpedoed the 3252-ton British freighter Sally Maersk, and the convoy made another emergency turn to avoid a surfaced U-boat. U-82 torpedoed the 7465-ton British CAM ship Empire Hudson less than two hours after Skeena regained station ahead of the convoy.

Daylight on 10 September brought several periscope sightings and emergency turns by the convoy before U-85 torpedoed the 4748-ton British freighter Thistleglen. Skeena and Alberni counterattacked and damaged U-85 with depth charges. Thistleglen sank with 5200 tons of steel, 2400 tons of pig iron, and 3 of her crew.

U-82 torpedoed the 7519-ton British tanker Bulysses that evening. U-82 then torpedoed the 3915-ton British freighter Gypsum Queen shortly after the convoy ordered an emergency turn. Gypsum Queen sank quickly with 5500 tons of sulfur and ten of her crew. Bulysses sank with 9300 tons of gas oil and 4 of her crew. Other ships in convoy rescued the survivors. The corvettes Chambly and Moosejaw observed the fireworks of these attacks and surprised U-501 while steaming to reinforce the escort. U-501 was first depth-charged by Chambly then rammed by Moose Jaw as the damaged submarine surfaced. The captain of U-501 jumped from the conning tower to Moosejaw's deck; and Moosejaw sent a boarding party to enter the submarine. Eleven Germans and one of the Canadian boarding party (Stoker William Brown)were lost when U-501 sank. U-501 was the first U-boat sunk by Canadian escorts.

Just after midnight on 10/11 September U-207 torpedoed the 4924-ton British freighter Berury and the 4815-ton British freighter Stonepool while Chambly and Moose Jaw were attacking U-501. Then U-432 torpedoed the 1231-ton Swedish freighter Garm and U-82 torpedoed the 5463-ton British freighter Empire Crossbill and the 1980-ton Swedish freighter Scania two hours later while Alberni, Kenogami and Moosejaw were rescuing survivors of Berury and Stonepool. U-43 launched torpedoes unsuccessfully, U-433 damaged a 2200-ton freighter, U-202 sank the crippled Scania, and U-105 sank a straggler.

On 11 September, the escort was reinforced by the naval trawler Buttermere and Flower class corvettes Wetaskiwin, Mimosa, and Gladiolus from convoy HX 147 and by the 2nd Escort Group consisting of the Admiralty type flotilla leader Douglas (Commander WE Banks senior officer), the Town class destroyer Leamington, the V and W class destroyer Veteran and S class destroyers Skate and Saladin. Leamington and Veteran dropped 21 depth charges on the afternoon of 11 September while investigating an RAF Coastal Command aircraft report of a U-boat ahead of the convoy. Postwar analysis indicated their attacks probably destroyed U-207.

Aftermath
With the arrival of these reinforcements further attacks by Markgraf were stifled. Though the group continued to shadow, it was unable to mount any further assaults.

The arrival on 12 September of the naval trawler Windermere and Town class destroyers St. Croix from convoy SC 41 and Columbia from convoy HX 147 allowed the remaining original escorts Skeena, Alberni, and Kenogami to leave for refuelling. On 13 September destroyers of the 2nd Escort Group departed for refuelling following the arrival of American destroyers Sims, Hughes and Russell. The last incident of the voyage took place three days later when U-98 torpedoed the 4392-ton British freighter Jedmore as the convoy approached North Channel on the late afternoon of 16 September.

Convoy SC 42 arrived in Liverpool on 20 September 1941. Sixteen ships totalling 68,259 GRT had been sunk and four ships (14,132 GRT) damaged. One ship had turned back. Forty four ships arrived safely and unharmed, and two U-boats had been destroyed, though one of these sinkings was not confirmed until after the war.