Admiralty Yard Craft Service

The Admiralty Yard Craft Service was the civilian service which operated auxiliary vessels for the British Admiralty, mainly in HM Dockyards or the vicinity. It was renamed the Port Auxiliary Service (PAS) on 1 October 1958 and the Royal Maritime Auxiliary Service in 1976

The service operated tugs, harbour ferries, launches, and lighters. Although some of its tugs were classified as ocean-going, it did not operate ocean-going supply vessels, which were the responsibility of the Royal Fleet Auxiliary. The Yard Craft Service crews answered to the Captain's Department in each dockyard.

The Fleet Coaling Service and the Admiralty Dredging Service were separate, but closely related, services. Ratings and engineers often transferred freely between vessels of the three services, although masters and mates had to be rated individually on each of the three types of vessel. The Fleet Coaling Service, renamed the Fleet Fuelling Service sometime between 1914 and 1926, operated harbour and coastal vessels carrying coal and fuel oil to Royal Navy vessels. Its masters did not have to be so highly qualified as the masters of the other two services and were paid considerably lower salaries. The Dredging Service was originally part of the Admiralty Works Department, but later transferred to the Civil Engineer-in-Chief's Department (between 1914 and 1926). By 1947, the other two services had fully amalgamated into the Yard Craft Service.

Vessels of the Service flew the Blue Ensign defaced by the yellow Admiralty anchor badge.

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