The Wave-class tankers are a class of fast fleet tankers in service with the Royal Fleet Auxiliary. The class is tasked with providing fuel, food, fresh water, ammunition and other supplies to Royal Navy vessels around the world. There are two ships in the class, RFA Wave Knight and RFA Wave Ruler. The ships were ordered to replace the aging Ol-class tankers RFA Olna and RFA Olwen.^[3] The two vessels have seen service in a number of locations, including anti-drug and hurricane relief operations in the Caribbean Sea,^[5][6][7] anti-piracy activities around the Horn of Africa,^[8][9] and deterrent patrols in the South Atlantic.^[10][11] As of early 2022, both ships were earmarked for "extended readiness" status (i.e. uncrewed reserve).^[12]

Quick Facts Class overview ...

Wave class

RFA Wave Ruler (left) carrying out a replenishment at sea with the frigate HMS Iron Duke in 2006
Class overview
Name	Wave class
Builders	VSEL (later BAE Systems Marine)
Operators	Royal Fleet Auxiliary
Preceded by	Ol class
Succeeded by	Tide class
In commission	8 April 2003–present
Completed	2
Laid up	2 (both ships in "extended readiness" - uncrewed reserve)
General characteristics [1][2][3]
Type	Fast fleet tanker
Displacement	31,500 tonnes approx
Length	196.5 m (644 ft 8 in)
Beam	28.25 m (92 ft 8 in)
Draft	9.97 m (32 ft 9 in)
Propulsion	Diesel-electric: 4 × Wartsila 12V 32E/GECLM diesel generators 25,514 metric horsepower (18.76 MW) 2 × GEC Alstom motors with Cegelec variable speed converters 19,040 metric horsepower (14 MW) 1 × shaft 18t thrust electric Kamewa bow thruster and 12t thrust electric stern thruster, both powered by Cegelec variable speed drives and motors
Speed	20 knots (37 km/h)
Range	10,000 nautical miles (20,000 km) at 15 knots (28 km/h)
Capacity	16,000 m3 of liquids (of which 3,000 m3 aviation fuel & 380 m3 fresh water) 125 tonnes of lubricating oil 500 m3 of solids 150 tonnes of fresh food in eight 20 ft refrigerated container units.
Complement	80 Royal Fleet Auxiliary personnel with provision for 22 Royal Navy personnel for helicopter and weapons systems operations
Sensors and processing systems	Surface search: E/F band Navigation: Kelvin Hughes Ltd SharpEye navigation radar[4] IFF: Type 1017
Armament	2 × DS30B 30 mm guns; 2 × 7.62 mm Mk.44 miniguns; 5 × 7.62 mm L7 machine guns; 2 × Vulcan Phalanx CIWS (all weapons removed given uncrewed reserve status)
Aircraft carried	1 × Merlin helicopter with full hangar facilities

Close

A contract was placed for the vessels in 1997 with Vickers Shipbuilding and Engineering Ltd (Marconi Marine VSEL). Construction of Wave Knight began in 1998 at VSEL's Barrow-in-Furness yard and the ship was launched in 2000.^[1] With the acquisition of Marconi Electronic Systems and its Marconi Marine subsidiary in 1999 British Aerospace became BAE Systems. BAE now owns VSEL in Barrow and the Yarrow and Govan shipyards on the Clyde. BAE transferred the construction of Wave Ruler to Govan in 2000 and the vessel was launched in 2001. Both vessels were commissioned in 2003.

The ships have the capability to supply fuel and other liquid cargo to vessels using replenishment rigs on port and starboard beams and through a Hudson reel-type stern rig. When providing support for amphibious operations, the ships are also able to deliver fuel to dracones positioned alongside. The equipment load includes cranes (for stores handling and abeam replenishment), steering and rudder gear, thyristor-controlled winch/windlasses and double drum mooring winches. Up to 16,000 m³ (570,000 cu ft) of liquids and 500 m³ (18,000 cu ft) of general solids can be carried. In addition, reverse-osmosis equipment is fitted enabling the production of 100 m³ (3,500 cu ft) of drinkable water per day.^[3]

The vessels were designed with double hulls to prevent or reduce environmental pollution from oil spills if damage is sustained to the outer hull.^[2]

The ships can operate a Merlin HM1 helicopter, or other helicopters of similar size, from a hangar and flight deck at the stern. On deployments to Atlantic Patrol Task (N) they have typically embarked a Royal Navy Lynx or a United States Coast Guard helicopter.

The vessels have a standard crew of 80 Royal Fleet Auxiliary personnel with provision for a further 22 Royal Navy personnel to conduct helicopter and weapons systems operations.^[3] They carry a full medical team and sick bay and are capable of distributing 2,000 emergency relief packages in times of crisis.^[13]

In June 2018 it was reported by the Brazilian press that the UK MoD had offered to sell one or both of the Wave-class tankers to Brazil.^[14] As early as 2010, BAE Systems had proposed providing Brazil with a variant of the Wave-class, tailored to meet the specific aviation, stores and personnel requirements of the Brazilian Navy.^[15]

As of June 2020, Wave Ruler was reported to be in reduced readiness^[16] but maintained in good condition and available for reactivation.^[17]

In February 2022, it was reported that both tankers would be placed in "extended readiness" (uncrewed reserve).^[12]

In June 2023, one report suggested that due to manning shortages in the RFA, both ships would be decommissioned and potentially sold abroad.^[18] However, in the same month James Cartlidge, the Minister of State, Ministry of Defence, stated that both ships were to be retained in extended readiness until 2028 with the option of potentially reactivating them if required.^[19]

• Wave Knight prepares to transfer fuel to the amphibious assault ship USS Bataan during a replenishment at sea.
• Wave Ruler underway with a United States Coast Guard Eurocopter HH-65 Dolphin helicopter embarked
• Wave Ruler (background) refuels USS Robert G. Bradley in the Pacific Ocean.
• Wave Ruler (foreground), USS Mahan, Almirante Latorre, Sachsen, and USS Samuel B. Roberts navigate in formation.
• Wave Knight resupplying French frigate Germinal.