The SC convoys were a series of North Atlantic convoys that ran during the battle of the Atlantic during World War II.
They were east-bound slow convoys originating in Sydney, Nova Scotia, Canada (designated as Sydney, Cape Breton by the Allied navies to avoid confusion with Sydney, Australia); from there they sailed to ports in the UK, mainly Liverpool. The Royal Canadian Navy base responsible for the Sydney operations was HMCS Protector.[1] The first convoy, SC 1, departed Sydney Harbour on 15 August 1940.[2]
For a time after the entry of the United States into the war the point of origin was switched to New York City, but congestion problems there resulted in a further move, this time to Halifax, Nova Scotia. However, the SC designation was retained throughout.
SC convoys ran from August 1940 until May 1945,[3] although they were suspended during the summer of 1944 when a number of escort groups were diverted to cover the Normandy landings. During this period all east-bound traffic sailed in the HX series, which ran as Fast or Slow convoys, and whose sizes were effectively doubled.
A total of 177 SC convoys ran during the campaign, totalling 6,806 ships. Only 3 failed to complete the passage: SC 52 suffered an attack shortly after leaving port, and was forced to return; and SC 62 and SC 63 were both scattered by appalling weather conditions which forced those ships to proceed independently.
Of these formations, 29 (around 20%) were attacked; they saw the loss of 145 ships ( though this number does not include stragglers, perhaps the same number again) and a further 18 lost in marine accidents (perhaps 340 in total; around 5%).
As these were slow convoys, composed of ships making 8 knots or less, they were correspondingly more vulnerable, and witnessed a disproportionate number of attacks.
The SC convoys were the subject of some of the major battles of the campaign. Of the 40 convoys which lost 6 or more ships, 11 of them were SC series.
Some notable SC convoy battles were: