This is a timeline for the Battle of the Atlantic (1939–1945) in World War II.
The first USS McCook (DD-252) was a Clemson-class destroyer in the United States Navy. Entering service in 1919, the ship had a brief active life before being placed in the reserve fleet. Reactivated for World War II, the ship was transferred to the Royal Navy and then to the Royal Canadian Navy and renamed HMCS St. Croix. Assigned as a convoy escort in the Battle of the Atlantic, St. Croix was torpedoed and sunk on 20 September 1943.
Hecht was the name of two "wolfpacks" of German U-boats that operated during World War II.
Vorwärts was a wolfpack of German U-boats that operated from 25 August to 26 September 1942, in the Battle of the Atlantic during World War II. They attacked several convoys, principally Convoy ON 127, sailing from Liverpool to New York, and sank fifteen ships for a total of 79,331 gross register tons (GRT), and damaged nine (81,141 GRT).
During the Battle of the Atlantic, British merchant shipping was formed into convoys for protection against German submarine attack. In March 1943 convoys HX 229 and SC 122 were the focus of the largest convoy battle of the war. Kriegsmarine tactics against convoys employed multiple-submarine wolfpack tactics in nearly simultaneous surface attacks at night. Patrolling aircraft restricted the ability of submarines to converge on convoys during daylight. The North Atlantic winters offered the longest periods of darkness to conceal surfaced submarine operations. The winter of 1942–43 saw the largest number of submarines deployed to the mid-Atlantic before comprehensive anti-submarine aircraft patrols could be extended into that area.
Convoy SC 121 was the 121st of the numbered series of World War II Slow Convoys of merchant ships from Sydney, Cape Breton Island to Liverpool. The ships departed New York City 23 February 1943; and were met by the Mid-Ocean Escort Force Group A-3 consisting of the United States Coast Guard (USCG) Treasury-class cutter USCGC Spencer, the American Wickes-class destroyer USS Greer, the British and Canadian Flower-class corvettes HMS Dianthus, HMCS Rosthern, HMCS Trillium and HMCS Dauphin and the convoy rescue ship Melrose Abbey. Three of the escorts had defective sonar and three had unserviceable radar.
Convoy SC 118 was the 118th of the numbered series of World War II slow convoys of merchant ships from Sydney, Cape Breton Island, to Liverpool. The ships departed New York City on 24 January 1943 and were met by Mid-Ocean Escort Force Group B-2 consisting of V-class destroyers Vanessa and Vimy, the Treasury-class cutter Bibb, the Town-class destroyer Beverley, Flower-class corvettes Campanula, Mignonette, Abelia and Lobelia, and the convoy rescue ship Toward.
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.
Convoy ON 154 - also ON(S) 154 or ONS 154 - was a North Atlantic convoy of the ON series which ran during the battle of the Atlantic in World War II. It was the 154th of the numbered series of merchant ship convoys Outbound from the British Isles to North America. It came under attack in December 1942 and lost 13 of its 50 freighters. One of the attacking U-boats was destroyed.
Convoy ON 127 was a trade convoy of merchant ships during the second World War. It was the 127th of the numbered series of ON convoys Outbound from the British Isles to North America and the only North Atlantic trade convoy of 1942 or 1943 where all U-boats deployed against the convoy launched torpedoes. The ships departed Liverpool on 4 September 1942 and were met at noon on 5 September by the Royal Canadian Navy Mid-Ocean Escort Force Group C-4 consisting of the Canadian River-class destroyer Ottawa and the Town-class destroyer St. Croix with the Flower-class corvettes Amherst, Arvida, Sherbrooke, and Celandine. St. Croix's commanding officer, acting Lieutenant Commander A. H. "Dobby" Dobson RCNR, was the senior officer of the escort group. The Canadian ships carried type 286 meter-wavelength radar but none of their sets were operational. Celandine carried Type 271 centimeter-wavelength radar. None of the ships carried HF/DF high-frequency direction finding sets.
German submarine U-402 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II.
Convoy ON 67 was a trade convoy of merchant ships during the Second World War. It was the 67th of the numbered series of ON convoys Outbound from the British Isles to North America. The ships departed from Liverpool on 14 February 1942 with convoy rescue ship Toward, and were escorted to the Mid-Ocean Meeting Point by escort group B4.
USS West Lianga (ID-2758) was a cargo ship for the United States Navy during World War I. She was later known as SS Helen Whittier and SS Kalani in civilian service under American registry, as SS Empire Cheetah under British registry, and as SS Hobbema under Dutch registry.
ON 207 was a North Atlantic convoy of the ONS/ON series which ran during the Battle of the Atlantic in World War II. It was the subject of a major U-boat attack in October 1943, the fourth battle in the German autumn offensive.
SC 129 was a North Atlantic convoy of the SC series which ran during the Battle of the Atlantic in World War II. It was one of several convoy battles that occurred during the crisis month of May 1943.
Convoy ON 144 was a trade convoy of merchant ships during the Second World War. It was the 144th of the numbered series of ON convoys Outbound from the British Isles to North America. The ships departed Liverpool on 7 November 1942 and were joined on 8 November by Mid-Ocean Escort Force Group B-6 consisting of the Flower-class corvettes Vervain, Potentilla, Eglantine, Montbretia and Rose and the convoy rescue ship Perth. Group B-6 had sailed without the destroyers Fame and Viscount which had been damaged in the battle for eastbound convoy SC 104. The United States Coast Guard cutters Bibb, Duane, and Ingham accompanied the convoy from the Western Approaches with ships that detached for Iceland on 15 November.
Convoy HG 73 was a trade convoy of merchant ships during the Second World War. It was the 73rd of the numbered HG convoys Homeward bound to the British Isles from Gibraltar. The convoy departed Gibraltar on 17 September 1941 and was found on 18 September and was attacked over the next ten days. Nine ships were sunk from the convoy before the submarines exhausted their torpedo inventory on 28 September. Surviving ships reached Liverpool on 1 October.
Convoy ON 92 was a trade convoy of merchant ships during the Second World War. It was the 92nd of the numbered series of ON convoys Outbound from the British Isles to North America. The ships departed from Liverpool on 6 May 1942 and were joined on 7 May by Mid-Ocean Escort Force Group A-3.
Convoy QS 33 was a trade convoy of merchant ships during the Second World War. It was one of the numbered QS Convoys from Québec to Sydney. The convoy was attacked in the early months of the Battle of the St. Lawrence, in the St. Lawrence River and Gulf of St. Lawrence, when German U-boats were making ad hoc forays deep into Canadian waters. The convoy was found on 6 September 1942 by U-165, which then destroyed two ships from the convoy while U-517 destroyed three.
Convoy SQ-36 was a trade convoy of merchant ships during the Second World War. It was one of the numbered SQ convoys from Sydney to Quebec. The convoy was found on 15 September 1942 by U-517, which then destroyed two ships from the convoy while U-165 sank another and damaged two.
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