HX convoys

The HX convoys were a series of North Atlantic convoys which ran during the Battle of the Atlantic in the Second World War. They were east-bound convoys and originated in Halifax, Nova Scotia from where they sailed to ports in the United Kingdom. They absorbed the BHX convoys from Bermuda en route. Later, after the United States entered the war, HX convoys began at New York.

A total of 377 convoys ran in the campaign, conveying a total of about 20,000 ships. 38 convoys were attacked (about 10%), resulting in losses of 110 ships in convoy; a further 60 lost straggling, and 36 while detached or after dispersal, with losses from marine accident and other causes, for a total loss of 206 ships, or about 1% of the total.

The HX designation perpetuated a similar series that ran in First World War Atlantic Campaign in 1917 and 1918. HX convoys were organized at the beginning of the Atlantic campaign and ran without major changes until the end, the longest continuous series of the war. HX 1 sailed on 16 September 1939 and included 18 merchant ships, escorted by the Royal Canadian Navy destroyers HMCS St. Laurent and HMCS Saguenay to a North Atlantic rendezvous with Royal Navy heavy cruisers HMS Berwick and HMS York.

These were initially considered fast convoys made up of ships that could make 9-13 knots. A parallel series of slow convoys, the SC series, was run for ships making 8 knots or less, while ships making more than 13 knots sailed independently, until 14-knot CU convoys were organized in late 1943. The largest convoy of World War II was HX 300 which sailed for the UK via New York on 17 July 1944, with 167 merchant ships. It arrived in the UK, without incident, on 3 August 1944.

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