The Royal Maritime Auxiliary Service(RMAS) was a British Government agency which ran a variety of auxiliary vessels for His Majesty's Naval Service (incl. Royal Navy, Royal Marines and Royal Fleet Auxiliary). The service from 2009 has been run by Serco and is known as Serco Marine Services.
The United States Maritime Commission (MARCOM) was an independent executive agency of the U.S. federal government that was created by the Merchant Marine Act of 1936, which was passed by Congress on June 29, 1936, and was abolished on May 24, 1950. The commission replaced the United States Shipping Board which had existed since World War I. It was intended to formulate a merchant shipbuilding program to design and build five hundred modern merchant cargo ships to replace the World War I vintage vessels that comprised the bulk of the United States Merchant Marine, and to administer a subsidy system authorized by the Act to offset the cost differential between building in the U.S. and operating ships under the American flag. It also formed the United States Maritime Service for the training of seagoing ship's officers to man the new fleet.
His Majesty's Naval Service is the United Kingdom's naval warfare and maritime service. It consists of the Royal Navy, Royal Marines, Royal Fleet Auxiliary, Royal Naval Reserve, Royal Marines Reserve and Naval Careers Service. The term Naval Service should be distinguished from the "UK Naval Services", which consist of the Naval Service and the Merchant Navy. The Naval Service as a whole falls under the command of the Navy Board, which is headed by the First Sea Lord. This position is currently held by Admiral Sir Ben Key. The Defence Council delegates administration of the Naval Service to the Admiralty Board, chaired by the Secretary of State for Defence.
SD Faithful is a Twin Tractor Unit Tug operated by Serco Marine Services in support of the United Kingdom's Naval Service. The ship was formerly operated by the Royal Maritime Auxiliary Service until its disbandment in March 2008. The vessel was originally built for the Royal Maritime Auxiliary Service in 1985.
SD Salmoor was a Sal-Class mooring and salvage vessel working at HMNB Clyde, and based at Great Harbour, Greenock. She was originally operated by the Royal Maritime Auxiliary Service, but after the organisations disbandment in March 2008 she was operated by Serco Marine Services.
SD Colonel Templer is an acoustic research vessel, renamed Seaway Endeavour in 2011 after she was sold to a Swedish shipping company. Between 1980 and 2011, she was in the service of the Royal Aircraft Establishment, the Royal Maritime Auxiliary Service and Serco Marine Services in support of the United Kingdom's Naval Service. Before 1980, Colonel Templer was known as MV Criscilla and worked as a stern trawler.
SD Powerful is a Twin Tractor Unit Tug operated by Serco Marine Services in support of the United Kingdom's Naval Service. The tug, built in 1985, was formerly operated by the Royal Maritime Auxiliary Service until its disbandment in March 2008.
DMS Maritime, formerly Defence Maritime Services, is a company providing port services to the Australian Defence Force and Marine Unit. It is a subsidiary of Serco.
Serco Marine Services is a Private Finance Initiative contract, with Serco Group, to deliver auxiliary services to His Majesty's Naval Service.
SD Nimble was a Twin Tractor Unit Tug operated by Serco Marine Services in support of the United Kingdom's Naval Service. The ship was operated by the Royal Maritime Auxiliary Service until its disbandment in March 2008.
The Government Service Ensign is a defaced Blue Ensign flown by vessels owned by the British Ministry of Defence for which no other ensign is appropriate. It is most commonly seen flown by warships undergoing contractors' trials before being commissioned into the Royal Navy, and former Royal Maritime Auxiliary Service vessels now operated by Serco Denholm.
SD Atlas was a tugboat in service with Serco Marine Services at HMNB Portsmouth, where she worked in support of the United Kingdoms Naval Service.
The Felicity class is a class of water tractors operated by Serco Marine Services in support of the United Kingdom's Naval Service. Historically the vessels were operated by the Royal Maritime Auxiliary Service, disbanded in March 2008.
SD Northern River is a large multi-purpose auxiliary ship operated by Serco Marine Services in support of the United Kingdom's Naval Service and is currently the largest ship operated by Serco Marine Services, both in terms of dimensions and gross tonnage.
SD Victoria is a worldwide support ship operated by Serco Marine Services in support of the United Kingdom's Naval Service, and currently the second largest ship operated by Serco Marine Services, after SD Northern River.
SD Bountiful is an ATD 2909-class tug operated by Serco Marine Services in support of the United Kingdom's Naval Service.
SD Tempest is an ART 8032-class tug operated by Serco Marine Services in support of the United Kingdom's Naval Service. SD Tempest was ordered specifically to handle the Queen Elizabeth-class aircraft carriers. However, the vessel also performs general harbour towage when not required in her primary role.
United Kingdom 
United Kingdom 
