This is a timeline for the Battle of the Atlantic (1939–1945) in World War II.
HMS Kempenfelt was a C-class destroyer built for the Royal Navy in the early 1930s. A flotilla leader, she saw service in the Home Fleet before World War II and the ship made several deployments to Spanish waters during the Spanish Civil War, enforcing the arms blockade imposed by Britain and France on both sides of the conflict.
Convoy ON 166 was the 166th of the numbered ON series of merchant ship convoys Outbound from the British Isles to North America. Sixty-three ships departed Liverpool 11 February 1943 and were met the following day by Mid-Ocean Escort Force Group A-3 consisting of the Treasury-class cutters Campbell and Spencer and the Flower-class corvettes Dianthus, Chilliwack, Rosthern, Trillium and Dauphin.
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 107 was the 107th 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 October 1942 and were found and engaged by a wolfpack of U-boats which sank fifteen ships. It was the heaviest loss of ships from any trans-Atlantic convoy through the winter of 1942–43. The attack included one of the largest non-nuclear man-made explosions in history, when U-132 torpedoed ammunition ships SS Hobbema and SS Hatimura - both were sunk, one exploded, with the German submarine also being destroyed in the explosion.
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 SC 130 was a North Atlantic convoy which ran during the battle of the Atlantic in World War II. It was the 130th of the numbered series of Slow Convoys of merchant ships from Sydney, Cape Breton Island to Liverpool. SC 130 was one of several convoy battles that occurred during the crisis month of May 1943.
Convoy SC 104 was the 104th of the numbered series of World War II Slow Convoys of merchant ships from Sydney, Cape Breton Island to Liverpool. During October 1942, a U-boat wolf pack sank eight ships from the convoy. The convoy escorts sank two of the attacking submarines.
Mid-Ocean Escort Force (MOEF) referred to the organisation of anti-submarine escorts for World War II trade convoys between Canada and Newfoundland, and the British Isles. The allocation of United States, British, and Canadian escorts to these convoys reflected preferences of the United States upon their declaration of war, and the organisation persisted through the winter of 1942–43 despite withdrawal of United States ships from the escort groups. By the summer of 1943, United States Atlantic escorts were focused on the faster CU convoys and the UG convoys between Chesapeake Bay and the Mediterranean Sea; and only British and Canadian escorts remained on the HX, SC and ON convoys.
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.
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.
Western Local Escort Force (WLEF) referred to the organization of anti-submarine escorts for World War II trade convoys from North American port cities to the Western Ocean Meeting Point near Newfoundland where ships of the Mid-Ocean Escort Force (MOEF) assumed responsibility for safely delivering the convoys to the British Isles.
The UG convoys were a series of east-bound trans-Atlantic convoys from the United States to Gibraltar carrying food, ammunition, and military hardware to the United States Army in North Africa and southern Europe during World War II. These convoys assembled in Hampton Roads near the mouth of Chesapeake Bay and terminated in various North African locations as Axis forces retreated from 1942 through 1945.
Convoy HX 212 was the 212th of the numbered series of World War II HX convoys of merchant ships from HalifaX to Liverpool. The ships departed New York City on 18 October 1942 and were met on 23 October by Mid-Ocean Escort Force Group A-3 consisting of the United States Coast Guard Treasury-class cutter USCGC Campbell, the destroyer Badger and the Flower-class corvettes Dianthus, Rosthern, Trillium, Dauphin, Alberni, Summerside and Ville de Quebec. The first five escorts had worked together previously, but the last three corvettes were attached to the convoy only for passage to the eastern Atlantic in preparation for assignments on Operation Torch. Summerside was the only escort equipped with modern Type 271 centimeter-wavelength radar.
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 ON 122 was a trade convoy of merchant ships during the second World War. It was the 122nd of the numbered series of ON convoys Outbound from the British Isles to North America. The ships departed Liverpool on 15 August 1942 and were joined on 17 August by Escort Group B6 of the Mid-Ocean Escort Force.
Convoy Battles of World War II occurred when convoys of cargo ships assembled for mutual defense, and were attacked by enemy submarines, surface ships, and/or aircraft. Most were in the North Atlantic from 1939 to 1943, and involved attacks by U-boat wolfpacks. Convoy battles also occurred in the Arctic Ocean, Mediterranean Sea and western Pacific Ocean.
Convoy HG 53 was the 53rd of the numbered series of World War II HG convoys of Homeward bound merchant ships from Gibraltar to Liverpool. Convoy HG 53 lost nine ships during a coordinated attack in February 1941. HG 53 was one of the few Atlantic convoys to have ships sunk by submarines, by aircraft, and by surface ships.
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