This is a timeline for the Battle of the Atlantic (1939–1945) in World War II.
HMCS Alberni was a Flower-class corvette that served in the Royal Canadian Navy (RCN) during the Second World War. The Flower-class corvettes were warships designed for anti-submarine warfare. The ship was constructed by Yarrows Ltd. in Esquimalt, British Columbia, laid down on 19 April 1940, launched on 22 August and commissioned on 4 February 1941. The corvette sailed east to join the RCN's fleet in the Atlantic via the Panama Canal, where upon arrival, the vessel began escorting trans-atlantic convoys in the Battle of the Atlantic. Alberni took part in the key convoy battle of Convoy SC 42. In 1942, the corvette was transferred to Allied convoy assignments associated with Operation Torch in the Mediterranean Sea. In 1944, Alberni was among the Canadian naval vessels assigned to Operation Neptune, the naval component of the invasion of Normandy and escorted support ships to and from the United Kingdom on D-day.
HMCS Skeena was a River-class destroyer that served in the Royal Canadian Navy (RCN) from 1931 to 1944. She was similar to the Royal Navy's A class and wore initially the pennant D59, changed in 1940 to I59.
HMCS Moose Jaw was a Royal Canadian Navy Flower-class corvette which took part in convoy escort duties during World War II. Together with HMCS Chambly, she achieved the RCN's first U-boat kill of the war. She was named after Moose Jaw, Saskatchewan.
German submarine U-96 was a Type VIIC U-boat of the German Navy (Kriegsmarine) during World War II. It was made famous after the war in Lothar-Günther Buchheim's 1973 bestselling novel Das Boot and the 1981 Oscar-nominated film adaptation of the same name, both based on his experience on the submarine as a war correspondent in 1941.
German submarine U-515 was a Type IXC U-boat of Nazi Germany's Kriegsmarine built for service during World War II. She was commissioned on 21 February 1942 and sunk on 9 April 1944. U-515 completed seven operational patrols and sank 23 ships, badly damaged two ships which later sank, and damaged two additional ships.
HX 79 was an Allied convoy in the North Atlantic of the HX series, which sailed east from Halifax, Nova Scotia. The convoy took place during the Battle of the Atlantic in the Second World War. One ship dropped out and returned to port, leaving 49 to cross the Atlantic for Liverpool. Two armed merchant cruisers and a submarine escorted the convoy to protect it from German commerce raiders.
The River class was a series of fourteen destroyers of the Royal Canadian Navy (RCN) that served before and during the Second World War. They were named after Canadian rivers.
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 94 was the 94th of the numbered series of World War II Slow Convoys of merchant ships from Sydney, Cape Breton Island, Nova Scotia, to Liverpool. The ships departed Sydney on 31 July 1942 and were met by Mid-Ocean Escort Force Group C-1.
Convoy ON 154 was a North Atlantic convoy of the ON convoys which ran during the battle of the Atlantic in the Second World War. 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 U-boat was sunk.
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 United States' 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 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.
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.
An Escort Group consisted of several small warships organized and trained to operate together protecting trade convoys. Escort groups were a World War II tactical innovation in anti-submarine warfare by the Royal Navy to combat the threat of the Kriegsmarine's "wolfpack" tactics. Early escort groups often contained destroyers, sloops, naval trawlers and, later, corvettes of differing specifications lacking the ability to maneuver together as a flotilla of similar warships, but rigorously trained in anti-submarine tactics to use teamwork emphasizing the unique sensors, weapons, speed, and turning radius of each ship. The development of these 'escort groups' proved an effective means of defending shipping convoys through the Battle of the Atlantic.
Arctic naval operations of World War II were the World War II naval operations that took place in the Arctic Ocean, and can be considered part of the Battle of the Atlantic and/or of the European Theatre of World War II.
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.
Kriegsmarine 
Royal Navy 
