The two variants are both based on the AEGIR design from Britain's BMT Defence Services but were built by Daewoo in South Korea with final outfitting in the UK and Norway respectively.

[8] The previous Tidespring earned a battle honour in 1982 for her service during the Falklands War, which included transporting a company of Royal Marines to recapture South Georgia.

[9] The Tide class are a 200.9 m (659 ft 1 in), 39,000 t[10] derivative of BMT Defence Services' AEGIR-26 design,[11] whose origins lie in a civilian tanker from Skipskonsulent of Norway.

As well as being safer, this means that Tides can go to places that discouraged their single-hulled predecessors - the recently decommissioned Rover-class vessels and Leaf-class tankers.

This policy is common among RFA vessels and follows that when a ship is deployed to more dangerous theatres, such as east of Suez, heavy dedicated armament is warranted.

[18] For instance, as of June 2021, RFA Tidespring has currently been fitted with her fore and aft Phalanx CIWS fixtures and both 30 mm cannons whilst deployed worldwide with CSG21.

[15] The design has been entered in a number of competitions, but as of March 2016[update] the only foreign order has been for an AEGIR-18R derivative from the Royal Norwegian Navy in 2013 (see below).

[26] In August 2016 it was reported that RFA Tidespring was still undergoing trials with builder Daewoo Shipbuilding and Marine Engineering (DSME) in South Korea;[27] procurement minister Harriett Baldwin has blamed "delays in finalising elements of electrical design and the installation of Multi-Cable Transit insulation in accordance with new legislative regulations" which have now been resolved.

[28] Tidespring reached the UK in spring 2017, docking at Falmouth on 2 April for seventeen weeks to fit weapons and communications gear.

[22] The flight deck can accommodate helicopters up to CH-53 Super Stallion size, and the hangar can operate one NH90 with level 2 maintenance or stow a second.

[22] Delivery was planned for 30 September 2016 followed by acceptance trials in Norway in early 2017, and then FOST in the UK and other exercises before full entry into service in January 2018.