Officially designated as 'LPDs'- Landing Platform Docks - these vessels were principally designed to support Royal Marine Commandos on Amphibious Operations by transporting and landing troops and equipment. The design of these two ships was based on the American Raleigh Class. During the Cold War they were tasked with supporting NATO's Northern Flank (Northern Norway) in the event of war with the Soviet Union. As the Navy's principle amphibious assets they could also act as a headquarters for an amphibious task group, a role put to use in the 1982 Falklands War, when Fearless hosted the Commodore Amphibious Task Group and his staff. In the mid to late 1980's the two vessels rotated the role of Dartmouth Training ship providing cadets from the Britannia Royal Naval College, with initial sea training and experience and were fully equipped with class rooms and teaching resources.

The Fearless Class LPDs were truly amphibious vessels. Vehicles drive onto the landing craft in the ship's internal dock from three vehicle decks, the main deck capable of carrying main battle tanks. When ready for amphibious operations 3,000 tons of Sea Water is pumped into ballast tanks at the stern of the vessel, lowering the stern by three metres. The stern door can then be opened, flooding the aft with water and allowing the four Landing Craft Utilities (LCU) and other small vessels to sail in and out of the vessel. The LCUs can carry up to 100 tons of equipment and are stored in the dock. Four smaller Landing Craft Vehicle and Personnel (LCVP) are carried on davits, two either side of the superstructure from which they could be lowered into the water. The LCVPs can carry up to 30 men or alternatively two land rover vehicles.

Troops could also be ferried ashore by helicopters and for this purpose the ships have a flight decks measuring 23 metres by 51 metres, capable of supporting most helicopters. During the Falklands Conflict (1982) a Sea Harrier was successfully landed aboard both vessels.
Fearless and Intrepid could transport a range of vehicles and military equipment which was stored on three internal vehicle decks reached by ramps which allowed access to the flight deck, or from the dock. Track laying and Combat Tractors along with Beach Armoured Recovery Vehicles (BARV) were carried but depending on the type of mission tanks, artillery, armoured vehicles, specialist snow, beach or desert craft could be accommodated. In the absence of equipment and vehicles the deck could also be used to transport extra troops or helicopters and similarly in the absence of aircraft the flight deck could also be used to transport vehicles and equipment. Accommodation was provided for 400 marines or in extreme cases up to 700 providing the vehicle deck and corridors are utilised. Both ships were capable of coordinating amphibious landings and exercises and have command and control facilities for a naval task force commander and his staff including an Assault Operations Command Centre.