Churchill wrote that the only thing that really worried him was the submarine menace. The Battle of the Atlantic reached its crescendo in 1943, when operations in North Africa drew escorts away from the Atlantic, and Britain depended utterly on the main North Atlantic convoy routes at the very time that German submarines, concentrated in “wolf packs,” redoubled their efforts, paying particular attention to the narrowing gap in mid-Atlantic left uncovered by land-based aircraft. ULTRA proved decisive, enabling escorts to find submarines with accuracy: the Germans lost 47 in May alone. Sinkings continued, but the battle was won by the end of the month.
Above, the Torch convoy at sea, November 1942. The convoy was kept under an air umbrella that reduced the risk of attack, but demands imposed on convoy escorts by the demands of North Africa were to influence the Battle of the Atlantic.
Arctic convoys ferried supplies to Russia. Here the cruiser HMS Belfast is at sea in northern waters, March 1943.
Most British warships relied on multi-barrelled automatic “pom-poms” for close defence against aircraft. This air spotter, binoculars at the ready, watches for hostile aircraft.
The cruiser HMS Sheffield, on the same convoy as the Belfast, has both forward turrets trained to the beam to avoid damage to their canvas blast screens. Nevertheless, one turret roof was torn right off by a wave.
Depth-charges dropped by a Canadian corvette ship. The Canadians, short of modern equipment and adequate destroyers, had a particularly hard war in the Atlantic.
A U-Boat commander at his periscope. German submarine crews had a horrifyingly high casualty rate: 40,900 men served in submarines during the war, and 28,000 perished. Admiral Dönitz, Commander-in-Chief of the German navy, lost both his sailor sons, one in a submarine.
The last moments of a freighter, seen from a submarine. From January to May 1943 Allied shipping loses averaged 450,000 tons per month.
U625 sinking after depth-charge attack by a Sunderland of 422 Squadron, Royal Canadian Air Force, March 10, 1944.
This U-Boat, attacked at periscope depth by a Sunderland, was brought to the surface by depth charges and then sunk.
Merchant seamen scramble aboard a U.S. Coast Guard cutter.
Firemen “Bonny” Bartell and “Snowy” Foster, both of Canning Town in East London, come up for a breather on a North African Convoy, July 1943.