HMS Ocean is an amphibious assault ship, the UK’s helicopter carrier and the fleet flagship of the Royal Navy. She is designed to support amphibious landing operations and to support the staff of Commander UK Amphibious Force and Commander UK Landing Force. She was constructed in the mid-1990s by Kvaerner Govan on the River Clyde and fitted out by VSEL at Barrow-in-Furness prior to trials and subsequent acceptance in service. She was commissioned in September 1998 at her home port HMNB Devonport, Plymouth.
She can deploy an Embarked Military Force (EMF) of a Royal Marines Commando Group from 3 Commando Brigade supported by aircraft and landing craft. The ship’s company includes 9 Assault Squadron (9 ASRM) from 1 Assault Group Royal Marines whose primary role is as an Amphibious Assault Squadron. Secondary tasks include boarding parties, beach reconnaissance and providing amphibious knowledge to the ships Command. Besides these roles they have responsibilities within the ship which include firefighting, watchkeeping and security. 9 ASRM is divided into a HQ unit, Landing Craft Troop, Signals detachment, Vehicle Deck Party and Assault Supply Team. The ship can carry four to six Apache AH1 helicopters operated by the Army Air Corps, as well as helicopters of the Royal Air Force, including the larger twin-rotor Chinook. Prior to their retirement, Ocean could transport up to fifteen fixed-wing Harrier aircraft of Joint Force Harrier in the ferry role, but was unable to operate as a fixed-wing aircraft carrier because she lacked the ski jump that is needed to launch a fully loaded Harrier.
Four Landing Craft Vehicle and Personnel (LCVPs) are permanently embarked and manned by 9 Assault Squadron Royal Marines.