First regular convoy

On 2 July 1917 a convoy designated HH 6 in British documents put to sea from Hampton Roads in Virginia. It was the first convoy of a regular series which from then on was to leave the American anchorage every four days. Both the British official history of the war at sea and C. Ernest Fayle’s history of seaborne trade regard this day as the start of the permanent transatlantic convoy (PL) service which the Admiralty had approved in mid-June.

The convoy’s number showed that it was not the first. After a successful trial with a convoy that left Hampton Roads on 24 May, four more convoys, each of about fifteen ships, were sent from there in June. All arrived safely, which according to the naval historian Henry Newbolt was the best answer to the officers who doubted the new system. These were still, however, sailings organised case by case. On 15 June the Admiralty ordered that convoys from Hampton Roads should leave every four days, alternately for ports on the east and south coasts of Britain and for western ports, as the report of the convoy committee had envisaged. Requisitioned tankers were to join the next convoy regardless of their port of destination.

HH 6 was the last “mixed” convoy, in which ships bound for ports on both coasts sailed together. On 6 July HH 7 left, made up only of ships bound for western ports, and from then on both kinds of convoy sailed regularly in turn. Across the ocean they were escorted by cruisers of the British North America and West Indies Squadron. By the end of July seven of its thirteen cruisers were employed solely on convoys, and four armed merchant cruisers from the 10th Cruiser Squadron and five armed steamers, on which retired admirals sailed as commodores, were sent to help them. In the approaches to the British Isles the convoys were taken over by destroyers. Convoys coming from the south met ships of the 2nd and 4th Flotillas from Devonport, and those heading for western ports met destroyers from Buncrana in the north of Ireland. There was no permanent flotilla there. In June four destroyers of the 14th Flotilla were sent to Buncrana, and in July four more from the 15th Flotilla.

During July further series were added: on 10 July from Sydney on Cape Breton Island, on 14 July from New York, where the US Navy soon took over part of the escort, and on 26 July from Gibraltar. By the middle of the month, therefore, four convoys from North America were leaving for Britain every eight days: two from Hampton Roads and one each from New York and Sydney. For the time being only ships sailing to Britain were included in convoys. Ships leaving its ports were not to receive escorts until August, and the Admiralty, for lack of warships, did not yet intend to extend the system quickly.

The results came within a few months. According to Fayle, in June, the last month before regular convoys, submarines sank 178 steamers of at least 500 gross tons. In September the figure was 87, and in the western approaches to the British Isles, where the most ships had been lost in the spring, for the first time not a single ship was sunk in the area of Cape Fastnet.