Bay-class landing ship

RFA Mounts Bay leaving Portsmouth
Class overview
Builders	Swan Hunter and BAE Systems Naval Ships
Operators	Royal Fleet Auxiliary  Royal Australian Navy
Preceded by	Round Table class
Succeeded by	Multi Role Support Ship (planned)
Cost	£596 million for 4 units £149 million per unit BAE ships cost £127 million[1] per unit to build
Built	28 January 2002-26 November 2007
In commission	13 July 2006-present
Completed	4
Active	4
General characteristics
Type	Landing ship dock
Displacement	16,160 tonnes (15,900 long tons)
Length	579.4 ft (176.6 m)
Beam	86.6 ft (26.4 m)
Draught	19 ft (5.8 m)
Propulsion	2 × Wärtsilä 8L26 generators, 6,000 hp (4.5 MW) 2 × Wärtsilä 12V26 generators, 9,000 hp (6.7 MW) 2 × azimuthing thrusters 1 × bow thruster
Speed	18 knots (33 km/h; 21 mph)
Range	8,000 nmi (15,000 km; 9,200 mi) at 15 kn (28 km/h; 17 mph)
Boats & landing craft carried	1 × LCU or 2 × LCVP in well deck 2 × Mexeflote powered rafts
Capacity	1,150 linear metres of vehicles (up to 24 Challenger 2 tanks or 150 light trucks) Cargo capacity of 200 tons ammunition or 24 TEU containers
Troops	356 (standard), 700 (overload)
Crew	70 (RFA, core only), 158 (RAN)
Armament	Fitted for: 2 × DS30B Mk 1 30 mm guns[2] 2 × Phalanx CIWS[3] 4 × 7.62mm Mk44 Miniguns (may be replaced by Browning .50 caliber heavy machine guns as of 2023)[4] 6 × 7.62mm L7 GPMG Individual outfit varies across class
Aviation facilities	Flight deck for helicopters up to Chinook-size; temporary hangar can be fitted
Notes	Derivative of the Enforcer ship design

The Bay class is a ship class of four dock landing ships built for the British Royal Fleet Auxiliary (RFA) during the 2000s. They are based on the Dutch-Spanish Royal Schelde Enforcer design, and replaced the Round Table-class logistics ships. Two ships each were ordered from Swan Hunter and BAE Systems Naval Ships. Construction work started in 2002, but saw major delays and cost overruns, particularly at Swan Hunter's shipyard. In mid-2006, Swan Hunter was stripped of work, and the incomplete second ship was towed to BAE's shipyard for completion. All four ships, Largs Bay, Lyme Bay, Mounts Bay, and Cardigan Bay had entered service by 2007.

Since entering service, the Bay-class ships have been used for amphibious operations, training of the Iraqi Navy in the Persian Gulf, counter-drug deployments in the Caribbean, and relief operations following the 2010 Haiti earthquake. In 2010, Largs Bay was removed from service as part of the Strategic Defence and Security Review. She was sold to the Royal Australian Navy (RAN) in 2011, who operate her as HMAS Choules.

Since 2020, the RFA has used the ships for littoral warfare as part of Littoral Response Groups. The ships are expected to serve with the RFA into the 2030s, after which they are expected to be replaced by new Multi-Role Support Ships.