Against a background of changing priorities and financial constraints, approval to complete them to a modified design was given in November 1954 and the three ships – Tiger, Lion and Blake – entered service from March 1959.

Described in one book as "hideous and useless hybrids" after conversion[1] and with limited manpower, resources, and better ships available, Tiger and Blake were decommissioned in the late 1970s and placed in reserve.

While the building schedules of Minotaur, Swiftsure and Defence were unaffected; construction of Blake and Tiger slowed; Hawke was not laid down until July 1943 and the eighth was never started.

Work on Defence was delayed by industrial relations, strikes, conditions, sub-standard facilities and low quality steel at Scotts, Greenock.

[6] The problems at Scotts and concern over the delay to Defence and the Tiger-class led the Director of Naval Construction to visit Scotts' yard in August 1943 with work stopped by striking riveters, carpenters and shipwrights [7] It was planned to launch Defence in April 1944 to complete in July 1945, for Hawke to launch in 1944 and commission mid-1945, with Blake and Tiger commissioning mid-1946.

A proposal was made in 1944 and again in February 1945 for two new cruisers and two light aircraft carriers to be delivered to the Royal Australian Navy; the UK offering HMS Defence and Blake[11][12][full citation needed].

[citation needed] In 1944–45, the RN, CNS and government thought the merging of the cruiser and destroyer categories[j] was too early, expensive and radical.

[citation needed][k] With the planned Neptune class cancelled, the suspended ships were the only cruiser hulls available and worth considering for rearmament.

[14] The Tigers were maintained as in some ways they were newer hulls with better internal and underwater protection, subdivision and compartments taking advantage of the removal of the hangar and X turret, Action Information centre, more light AA, pumps and electric generating capacity.

The original decision to delay the Tigers in the late 1940s had been to reassess cruiser design and the provision of effective anti-aircraft (AA) fire-control to engage jet aircraft which was beyond UK industrial capability at the time.

[19] Consequently, higher priority was given to the battleship HMS Vanguard, the Battle-class destroyers and the two new Audacious-class aircraft carriers (Eagle and Ark Royal) for allocation of 26 US-supplied medium-range anti-aircraft gun directors (which had been delivered under Lend-Lease in 1944/5)[20] The US version of the Type 275 High Altitude/Low Altitude DCT were stabilised and could track multiple air targets of Mach 1.5+.

These US directors were superior to the British built Type 275 which was the only medium-range AA fire control until 1955 and could barely distinguish transonic targets at Mach 0.8.

The automatic twin 6-inch guns for the secondary role of defence of and attack on trade also had some very high level (up to 8-mile altitude) anti-aircraft capability.

In historical terms it represented a light armament and similar US weapons introduced on USS Worcester had experienced considerable problems with jamming and had performed below expectation.

Even six-inch bombardment was increasingly unacceptable to the Royal Navy after Korea and was allowed only on the first day of Operation Musketeer after strong political opposition.

Against the apparent Soviet threat of Sverdlov cruisers acting as raiders against merchant vessels, the Tigers lacked the range [30] and armament to challenge the Soviet ships, on paper, while other RN officers thought a couple of Darings or Type 41 frigate anti-aircraft frigates were all that was needed to challenge the inexperienced Russian crews[citation needed].

[clarification needed] Churchill was determined to limit the defence budget with a view to developing nuclear weapons and less vulnerable RAF aircraft.

Blake was essentially an experimental ship with all-electric turrets able to engage Mach 2.5 air targets but was put in reserve in 1963 for lack of technical staff.

[39][40] Lion had deteriorated after eight years in Gareloch before reconstruction and had to be withdrawn from operations "East of Suez" in 1963 due to boiler, mechanical and armament problems.

While the electric 3-inch/70 AA systems were excellent they required intensive maintenance and excessive manpower and fitters, the twin Mk 26 6-inch automatic guns were a 'disaster' constantly jamming and rarely fulfilling their basic 30 second burst fire min capability [41] [42] HMNZS Royalist, with some Royal Navy crew, was reactivated as a surface escort for carrier groups in Southeast Asia in 1964 to deter the threat of the Sverdlov cruiser bought by Indonesia and in 1965 to support the amphibious carriers with air defence and general fleet support.

[43][44] By 1964 the Conservative Government and half the naval staff saw the Tigers as no longer affordable or credible in the surface combat or fleet air defence role and would have preferred to decommission them but given they were technically only three years old and built at immense expense, scrapping them was politically difficult.

[46] Cancellation of the last four of the ten planned County-class guided missile destroyers[r] and moving two or three of the Tigers to operational reserve [47] would offset the Escort cruiser cost and replacing the Tigers or fully funded the more 'conventional cruisers, intended as replacement ships in 1960 [48] (a) modified versions of the County-class built to the same hull dimensions and armament without Seaslug, to carry 4-6 Wessex helicopters or (b) the variant models of the Counties proposed by the RAN or (3) An enlarged version of the County design built to cruiser standards with additional workshops, parts and stores carried and some armour protection with provision for three Wessex and the American Tartar system.

[55] To avoid the political problem of scrapping new cruisers as well as the aircraft carriers, the Labour Government elected in October 1964 decided to retain large ships for command and flagship roles and accepted the RN and MoD argument that three Tiger cruisers would replace the anti-submarine warfare role previously provided by aircraft carriers.

At the time the Royal Navy was mostly concentrated on east of Suez operations and the anti-submarine deterrent role was to counter slow Indonesian and Chinese diesel-powered submarines.

[citation needed] The proposed class of four large Type 82 destroyers (planned to accompany the CVA-01 aircraft carriers) fitted with nuclear Ikara anti-submarine missiles could have been a more reliable nuclear deterrent,[citation needed] but the Ikara was ultimately fitted only to carry conventional Mark 46 torpedoes and due to the 1966 Defence White Paper only one Type 82 air defence destroyer, HMS Bristol, was built as a testbed for the weapon technologies.

[59] Cutbacks in Royal Navy funding and manpower, under the new Conservative government and the belief in the Hawker Siddeley Nimrod maritime patrol aircraft and submarines for anti-submarine operations, reduced the need for the class.

When Blake was decommissioned in 1979, she was the last cruiser to serve in the Royal Navy and her passing was marked on 6 December 1979 when she fired her main guns for the last time in the English Channel.