The Reconstructions

THE RECONSTRUCTION OF WARSHIPS to counter both age and obsolescence developed between the wars as an expedient to ensure that both numbers and quality were to some extent maintained in the face of both budgetary constraints and treaty restrictions. Major warships reconstructed before the outbreak of the Second World War included the battleships Warspite, Queen Elizabeth and Valiant, the battlecruiser Renown and the cruiser London. There is a fine line between reconstruction and modernisation, and in this account the main criteria used to distinguish between the two will be the submission of a project for approval by the Board of Admiralty.


At the end of the war the Royal Navy possessed six fleet carriers all of which unfortunately lacked hangars with sufficient height to accommodate modern aircraft, a disadvantage of the armoured hangar design. A limitation on the weight of the aircraft carried was another constraint. Hangar heights and aircraft weights were: Illustrious 16ft and 20,000lbs; Formidable and Victorious 16ft and 14,000lbs; Indomitable 14ft upper hangar, 16ft lower hangar and 14,000lbs; Implacable and Indefatigable 14ft both upper and lower hangars and 20,000lbs. A hangar height of 17ft 6in and the ability to handle aircraft with a weight of 30,000lbs was needed, features which were incorporated in the design of the new Ark Royal and Hermes classes. The deficiencies were a major constraint on the effectiveness of the existing carriers and tentative steps towards the necessary modernisation were being considered as early as September 1945.


The newly reconstructed Victorious leaving New York on 3 August 1959. Prominent among the air group arrayed on deck are Scimitars along the angled deck and a pair of AEW Skyraiders right aft; other aircraft visible are Gannets and Sea Venoms.

(Royal Naval Museum)

In November 1945 the Deputy Controller indicated that nine fleet aircraft carriers would be needed in 1950, of which three would be the Ark Royal class (the contract for the original Eagle had not then been cancelled), the other six being the Illustrious and her five contemporaries. Anything less than a full reconstruction was not recommended. The cost of reconstruction was said to be £2.5 million compared with £7 million for a new aircraft carrier. Nevertheless, the Fifth Sea Lord, who was responsible for aircraft in the fleet, considered it was not worth while modernising Illustrious, the money saved being better put towards the cost of a new ship. In any case there was now no money for the project so the subject was deferred for 6 months.1

The subject came up for discussion again in the summer of 1946. Part of the debate centred around the question of closed or open hangars, a controversy which had plagued the design of the cancelled Gibraltar/Malta class carriers. The Director of Naval Construction, Sir Charles Lillicrap, was far from convinced that an open hangar was the way ahead and he was anxious to avoid any vacillation. The arguments were finely balanced, with the Americans initially in favour of an open hangar, a position changed after wartime experiences in the Pacific. The penalty of the closed armoured hangar was a constraint on aircraft operations, but the advantage was that it was not so easy to put the ship out of action. Lillicrap was particularly anxious to avoid the Gibraltar state of affairs where firstly a closed hangar design was approved, then an open hangar was wanted and later it was decided that the redesigned ship was 50ft too long, only for the project to be finally cancelled, with a considerable waste of design effort. He also indicated that 9 to 12 months notice would be needed before the ships could be taken in hand. The outcome of these deliberations was the setting-up of a small committee under the Assistant Chief of Naval Staff (Air) which was to decide the future of each carrier on its merits. No decision on what was described as the ‘vexed question’ of open versus closed hangars was to be taken until the results of the Bikini Atoll atomic experiments had been examined.2

In January 1947 the committee held its first meeting. The Director of Naval Construction indicated that the carriers should have a life of a further 20 years, which would take them up to 1967. It was decided that the order in which modernisation should be undertaken was Formidable, Victorious, Indomitable, Illustrious, Implacable and lastly Indefatigable. The easiest projects were Formidable and Victorious with the Implacable and Indefatigable being the most difficult. The committee held a second meeting later in the month when broad decisions were taken. An intermediate modernisation was felt not to be worthwhile, but owing to financial constraints a full modernisation was not possible at that time. All six carriers were said to have long defects lists and, prior to placing in reserve, repairs were to be confined to remedying critical defects only. It was also concluded that the Bikini tests did not affect the plan, which indicates that it was decided to retain closed hangars. The final report of the committee was submitted in April 1947. Full modernisation of Formidable and Victorious was approved to what was described as an ‘improved Hermes’ standard. The ships, which were described as a ‘Fast Armoured Hermes’, would carry 48 aircraft. By comparison the Hermes carried 45 whilst Ark Royal carried 84. It was to be January 1948 before the Board of Admiralty approved this project in principle.3

Preparation of the design commenced in February 1948, the aim still being for Formidable to be the first ship. Progress was slow, however, and it was to be June 1950 before a Legend was prepared. The ship now had a deep displacement of 33,000 tons (27,180 tons standard). The eight 4.5in twin mountings were to be replaced by six twin 3in/70 cal. The 3in flight deck armour was retained but the ship was to be rebuilt from the hangar deck upwards. The beam was increased, which in turn meant moving the side armour and generally rearranging all compartments outside the machinery spaces. All cables and wiring was to be renewed with generating capacity doubled and new auxiliary machinery installed. The island was also reconstructed. The cost of the project was unclear, however, as the Director of Dockyards did not have sufficient information to formulate an estimate, an ominous portent. By now it had been decided that Victorious would be the first ship as she was in a better state than Formidable which had a distorted flight deck, propeller shaft defects and other outstanding problems which would need a lengthy refit to correct.

Work on the reconstruction started at Portsmouth Dockyard in October 1950, the intention being to complete the work by April 1954; but the project was to be dogged with alterations, the first of which was a decision to install the US 3in/50 cal. which was taken in February 1951 owing to delays in the development of the British 3in/70 cal. By June 1952 the provision of an angled deck was being considered following successful trials in the light fleet carrier Triumph in February 1952. By May 1953 it was decided that an 8½° angled deck should be fitted. In July 1953 it was decided to fit a Type 984 radar, a not inconsiderable undertaking. It was also now realised that the boilers would only run until 1964 without a further extensive refit, so it was decided to re-boiler the ship. This turned out to be a somewhat contorted and expensive exercise. The first difficulty was removing the old boilers, reconstruction having already reached the point where the armoured deck had been refitted, resulting in a considerable amount of completed work being dismantled. The original idea had been to produce boilers of similar design to those originally fitted with existing auxiliary machinery and systems being retained, at an estimated cost of £250,000. The old boilers were removed and duly destroyed, but it was then found that modern boilers would be needed to meet the large intermittent steam requirements of the steam catapult. Provision of these new boilers plus some new auxiliary machinery resulted in the additional costs rising to £607,000. The Board of Admiralty approved the scheme in December 1953, the figure quoted being £650,000 to provide a small margin.

A new Legend produced in July 1955 quoted a deep displacement of 35,500 tons (30,532 tons standard). Completion was now due in June 1957. The complexity of the task proved to be much greater than any earlier project and it was clear that there was a need for improved production control systems and procedures. It was to be 1958 before the work was completed. The cost of the conversion escalated throughout the life of the project. In December 1947 it was anticipated that £5 million (excluding the cost of the guns) would be spent on each ship. By August 1950, when the Victorious was in dockyard hands, the total cost was £5.4 million. By October 1950, with more reliable data available on dockyard costs, the figure had escalated to £7.7 million. By March 1952 an up-to-date estimate came out at £11 million, which itself increased to an estimated £14.16 million by December 1953, taking into account re-boilering, the angled flight deck and the Type 984 radar. The final figure, £30 million, was far more expensive than ever envisaged; nevertheless the reconstruction was a success for a very useful modern carrier equipped for handling, operating, controlling and detecting modern jet aircraft was the result.4

The next ship in line was now Implacable, which it was planned to take in hand at Devonport in April 1953 and modernise her on the lines of Victorious. She would have

been followed by Indefatigable. Deep displacement would have been 36,000 tons. But by October 1951 the project had been postponed for 2 years and the delays to Victorious were becoming a cause for concern. By June 1952 the Admiralty decided that it was the wrong policy to spend large sums of money on the modernisation of old carriers and that Victorious would be the only major conversion.5


This light fleet aircraft carrier, originally named Elephant, was ordered from Vickers Armstrong, Barrow under the 1943 New Construction Programme. She was one of eight ships of the Hermes class, four being cancelled at the end of the Second World War, including the ‘original’ Hermes. Progress on all the class was slow, with three of the ships being completed in 1953–4. In the case of Hermes the Admiralty indicated to the shipyard in December 1948 that the ship was to be completed by the end of 1952. However, priority was given to the completion of the aircraft carrier Melbourne for the Royal Australian Navy with the result that delays became severe and there were periods when construction stopped altogether. However, advantage was taken of the delays to substantially modify the design.

The first batch of major changes was made in 1951 when it was decided to fit two steam catapults, incorporate a side lift and provide improved arresting gear. The installation of a side lift in an aircraft carrier with a closed hangar is far more difficult than it may appear at first sight. The structure of the ship acts as a box girder with the flight deck and the bottom taking most of the bending stresses whilst the sides of both the ship and the hangar resist the shear forces and prevent the whole structure from buckling. Cutting a large hole in the hangar and ship’s side weakens this structure considerably. A workable solution was produced by NCRE (see photograph of the structure in Chapter 12). They used what was then the fairly new method of photo-elasticity in which a large model of the structure was made in Perspex. This was illuminated with polarised light and put under load. Bands of light and dark showed the stress pattern and the number of fringes would give an indication of the magnitude of the stress. The model was fairly easy to alter so amendments could be made until the best answer was obtained. Sliding doors were then fitted in the ship to keep the hangar ‘closed’ as a fire precaution. The side lifts installed in Hermes and Ark Royal worked, but they were heavy and there was a limitation on the size of aircraft carried.


Hermes in 1966, with a pair of Scimitars on deck. Originally a sister of Centaur, as completed this ship revealed little beyond the general appearance of the hull to signify their relationship.

(Royal Naval Museum)

The structure needed to support a steam catapult also proved difficult to design, one major problem being the severe impact at the fore end where the heavy shuttle had to be brought to a stop in a few feet. A replica of the catapult structure was built and tried in a large test frame measuring 69ft × 33ft × 39ft where loads of up to 2000 tons could be applied. The structure of the catapult for Ark Royal was tested there in 1953 and the lessons learned incorporated in the design used in Hermes.

In 1953 further major works were authorised, including the fitting of a fully-angled deck and a Type 984 radar system. The result of all the additions incorporated was that the standard displacement rose from 18,410 tons (23,800 tons deep) in 1944 to 23,460 tons (27,800 tons deep) in 1954. The deep displacement was at the acceptable limit and was a cause for concern as the design of some of the radar and gunnery equipment had not been fully developed. If further additional equipment weight had to be accepted then the weight of other features in the design would have to have been reduced as compensation. Measures to save weight were fairly extreme, ranging from 50 tons being saved by using plastic-covered cable wherever possible instead of lead covering, to 5 tons saved by using light alloy in the bridge structure. Careful attention to detail saved about 120 tons over seventeen items. The speed of the ship was inevitably affected but it was still expected that 25kts could be achieved when the ship had been out of dock in tropical waters for six months. However, when the steam catapult was operating under the most severe requirements then a further reduction of in full speed of 1.5kts was expected. Endurance was also reduced. The original requirement was 6000 miles at 20kts in the tropics when the ship had been out of dock for six months. This figure now reduced to 4800 miles, a small part of the reason being that a change in the calculation rules meant that the original figure would have been 5 per cent lower.

The aircraft complement in 1954 was expected to be eight Scimitars and eight Sea Vixen fighters, eight Gannets, four Skyraiders (presumably for ASW and AEW respectively), and two helicopters. Larger aircraft could not be accommodated as their weight would place them beyond the capacity of the catapults.6


Hermes displays her revised layout as a commando carrier while replenishing at sea from USS Neosho in June 1974. To starboard of the oiler is USS Vreeland, a Knox class destroyer escort.

(Royal Navy)

Hermes operated as a front-line aircraft carrier from completion in 1959 until 1971 when she was converted into a commando carrier operating Wessex helicopters, losing catapults, arrester wires and her Type 984 radar, which was replaced by a Type 965; but the basic structure of the ship was largely unaltered. In 1977 she became an ASW carrier with a complement of Sea King helicopters, which were quickly supplemented with a squadron of Sea Harriers for air defence, a 7° ski jump ramp being installed to improve the performance of the aircraft. The ship filled a gap pending the arrival of the three Invincible class, which at that time were described as through-deck cruisers, and as such she played a key role in the Falklands War of 1982. She was finally paid off in 1984 and sold to India who have renamed her Viraat.7 Although too small to be an effective fleet carrier in her later years, Hermes proved to be a remarkably flexible ship which served the Royal Navy well. She can be regarded as highly successful.


Hermes comes home from the Falklands battles on 10 February 1983. Note the streaks of rust on the sides of the ship. All other members of the task force returned with their paintwork in virtually pristine condition. Work on Hermes started in 1944 when techniques for preserving steel were not so advanced. D K Brown worked on her as an apprentice in 1947/48.

(Royal Navy)

The Trials Cruiser Cumberland

In 1951 the old ‘County’ class cruiser Cumberland completed a refit as a trials cruiser. The obvious trials were of new gunnery systems but there were also other important tests. At first she mounted a single 4.5in and a 40mm STAAG with a ‘Battle’ class director, all situated on the starboard side abreast the funnels. Another 4.5in mounting was later fitted on the port side. By 1953 the ship had a twin 3in/70 cal. in ‘Y’ position followed by a twin 6in Mark XXVI in ‘B’ position. Both mountings, which were fitted in the Tiger class, were controlled by an MRS3 located on the bridge. Other trials included pre-wetting to reduce the effect of nuclear fallout. She was also fitted with four pairs of small non-retractable stabiliser fins. These were less effective than a single pair of high aspect ratio retractable fins but were much easier to install. Most of the work was devoted to improving the control system. The ship was also fitted with three-bladed noise-reduced propellers based on those successfully tried in the wartime destroyer Savage, but for some reason they did not work so well in Cumberland. The old cruiser paid off at the end of 1958.8

The ‘Ca’ Class Destroyers

The eight destroyers of this group were all completed in the last months of the Second World War. By 1951 they were obsolete and required modernisation to make them effective units of the fleet. The main function of the ships as modernised would be to screen heavy forces against attack by submarines, aircraft and light forces and to attack enemy light forces and trade. Secondary functions were to supplement cruisers for independent operations, support combined operations and attack heavy ships with torpedoes. The work was extensive and the most comprehensive given to any of the wartime destroyers which were not converted to frigates. The result was a class of ships with improved anti-submarine and anti-aircraft capabilities.


Cumberland being given a thorough dousing in ‘prewetting’ trials to test ability to disperse contamination.

(Crown Copyright)


Royalist in July 1956 after a major refit. She was the only Dido or Modified Dido class cruiser to be given extensive modernisation which included a new bridge structure, lattice masts, new sensors and Bofors 40mm close-range anti-aircraft armament. The result was a particularly handsome ship, but like many warships of her era she suffered badly from hull corrosion in later life.


The bridge structures were all rebuilt, incorporating an enlarged operations room, four of the class acquiring a frigate-type bridge. The No. 3 4.5in mounting was removed to enable a double Squid anti-submarine mortar to be fitted. Also removed was the after set of torpedo tubes, which enabled the after deckhouse to be extended forward. The three remaining 4.5in guns were controlled by a Mark 6M director fitted with FPS 5 (Fly Plane System). A Type 275 radar was also provided for this purpose. The close-range armament consisted of a twin 40mm Bofors Mark V with STD (Simple Tachymetric Director) on the aft superstructure and two single 40mm Bofors Mark VII abreast the bridge. Provision was made for Type 147F, 162 and 166 sonars and an enlarged sonar instrument room. The depth charge store was converted to a Squid magazine, which could stow 60 projectiles (10 salvoes). Radar carried included Type 293Q, a surface and low-angle air search target indicator set, and Type 974, a Decca navigation set. The generating capacity was increased with a 150 kW machine replacing a 50 kW set in No. 1 boiler room; a 150 kW set was installed in No. 2 boiler room with a 50 kW set in the gearing room being retained. All the additions exacted a price. Deep displacement was now 2675 tons against the original designed displacement of 2485 tons. The maximum speed was now 30kts with the ship clean in temperate waters. Some 50 tons of permanent ballast was needed to maintain stability. The ship had also reached the point where no further weight additions were possible, any increase in the stresses imposed on the ship’s structure being unacceptable. The class proved useful units of the fleet, the first of the class not being broken up until 1967. One ship, Cavalier, has been preserved and is now at Chatham Historic Dockyard.9

The Tiger Class

The three surviving cruisers of the Tiger class were a prewar design with some war experience incorporated in improvements. The main development had been the substitution of the triple 6in mounting Mark XXIV for the Mark XXIII, the gain being an increase in elevation from 45° to 60°. Manufacture of this armament was nearing completion when construction of the three ships was suspended in the summer of 1946.10

In November 1947 a full investigation was made into fitting the new twin 6in Mark XXVI mounting in the class, this armament having been specified for the cancelled Minotaur class cruisers. Two mountings could be carried, one forward and one aft. In addition three of the new twin 3in/70 cal. could be mounted. Another scheme considered at this time was the elimination of the 6in armament and the fitting of six twin 3in/70 cal. in substitution. By March 1948 it was decided that the 6in scheme should proceed, the all-3in armament not being worthwhile because it would leave the ship vulnerable if it ever had to encounter an armed merchant cruiser. The ships, however, remained suspended, with Blake and Tiger being the responsibility of the shipyards whilst Defencewas part of the Reserve Fleet Organisation. When the Korean War broke out there were thoughts of completing the ships with two 6in Mark XXIV mountings. These guns would have been mounted forward in ‘A’ and ‘B’ positions. Two twin 4.5in Mark VI were to be mounted aft in ‘X’ and ‘Y’ positions, with either a further pair of sided twin 4.5in Mark VI or two single 4.5in Mark V sided in ‘P1’ and ‘S1’ positions. The 6in mountings were in store at Rosyth Dockyard, some incomplete. This option was quickly abandoned when it was found that the ships would not be ready before the end of 1953, unfinished work on the gun mountings being a major part of the task.11


Tiger class with all 3in/70 cal. armament. This option with six twin 3in/70 cal. mountings was considered in November 1947 with the adopted twin 6in Mark XXVI and three twin 3in/70 cal. design. Note the size of the 3in/70 cal. mountings, which do not look out of place on a hull designed in 1936/37 to carry four triple 6in Mark XXIII mountings. (Drawing by John Roberts from original in NMM ADM 138/777)


Tiger in 1959. She is a new ship, but her replacement in the fleet, the ‘County’ class guided-missile destroyer, is only a few years from completion.

(Royal Naval Museum)

Design work moved forward slowly and as late as 1954 there were considerable doubts within the Admiralty as to whether it was worthwhile completing the three ships, the Radical Review being underway. They had now been laid up for 8 years. Blake and Tiger were said to be ‘in first class condition’ although Defence, which languished on moorings, was said to be ‘not so good’. In July 1954 the Board of Admiralty at long last approved the legend and sketch design of the redesigned ships. The class was now seen as providing escort and anti-aircraft support to convoys and carrier task groups. There were clearly severe limitations for by the time the ships were complete they would have been in the water for at least 12 years, whilst the hulls and machinery were of pre-war design and layout in all major respects. There was also going to be considerable congestion within the hull structure with accommodation standards being low due to the incorporation of equipment not specified in the original design.

The reconstruction was extensive. All the superstructure, gun supports, minor bulkheads and most of the services were stripped out. In addition all auxiliary machinery and equipment had to be modified or replaced so that it could operate on an entirely AC electrical system. Reboilering was considered but was ruled out by the Board of Admiralty, as the advantages would not compensate for the delay and expense incurred. The displacement in deep condition was now 11,900 tons, the result of this increase and other improvements such as air conditioning being a reduction in speed to 29.25kts when the ship operated in the tropics and had been out of dock for 6 months. Endurance was reduced by 440 miles to 4190 miles when the ship had a clean bottom. The revised main and secondary armaments were as first envisaged in 1947. The cost was put at £6 million each with 3 years being taken to complete each ship. A new cruiser of comparable size and armament was said to cost about £12 million and would require 5 years to complete. When it was decided to complete the ships it was appreciated that vessels mounting guided missiles would be their ultimate successors, but it was expected that they were at least 10 years away. The Tiger class at this stage in their careers can be considered as very much a stop-gap.12 The work took rather longer to complete than was anticipated, with Tiger completing in March 1959, Lion (ex-Defence) in July 1960, and Blake in March 1961, the latter ship only 20 months before the first of the new ‘County’ class guided-missile destroyers was commissioned. It also proved more expensive than projected with Tiger costing £13,113,000, Lion £14,375,000 and Blake £14,940,000. The effects of inflation made themselves felt but were again not the only factor in the escalating figures.13

The entry into service of the guided-missile destroyers and a need to modify long-term new construction plans due to the advent of the Polaris submarines caused the postponement of an escort cruiser programme. The result was a new role being found for the Tiger class. The escort cruisers would have provided an anti-submarine helicopter force for the fleet, a requirement which continued. It was concluded in the autumn of 1963 that the conversion of the Tiger class provided the quickest and most practical means of meeting the need for anti-submarine helicopters in the fleet. The War Office, however, were concerned at the reduction in bombardment support for the Army but after consideration this was accepted.

Three schemes were considered:

•Scheme ‘X’ provided deck space for one Wessex helicopter with rotors spread and hangar stowage for three. There would have been no maintenance facilities and the after 6in mounting would have been removed.

•Scheme ‘Y’ provided deck space for two Wessex helicopters with rotors spread but there was only enough space to land one at a time. There would have been hangar space for four helicopters and maintenance facilities would have been at the level provided in the new guided-missile destroyers. The after 6in and both after 3in mounts would have been removed.

•Scheme ‘Z’ provided deck space for two Wessex helicopters with rotors spread and two could take off and land at the same time. There was hangar space for four and the same level of maintenance could be achieved as specified in Scheme ‘Y’. The after 6in and both the after 3in were again removed.

Initially it was expected that the work could be completed quickly in conjunction with long refits which were now unavoidable because of the long delay imposed on the escort cruiser programme. The time needed to do the work was 9 months (‘X’), 12 months (‘Y’) and 15 months (‘Z’), with costs put at £1.25 million, £1.5 million and £2 million per ship respectively.

Scheme ‘Z’ was regarded as the best option and although the most expensive was the one chosen. The total cost of the programme was soon found to be somewhat larger being put at £12 million in total for all three ships for Dockyard work which included the refits, plus an additional £10.5 million for Wessex 3 helicopters spread over 1964–8. The programme was considered worthwhile even though the converted ships were initially expected to have a life of only 6 years, soon prolonged to 10 years. One gain achieved by the scheme was in the political sphere, for criticism of the Tiger class in their role as conventional cruisers was still being felt. One problem anticipated was the provision of trained aircrew. There was already a deficit of 37 helicopter pilots in the Fleet Air Arm and now it would be necessary to train 75 pilots in 1964. It was thought possible that the entry would fall short and that provision of the pilots would take a year longer than the work on the ships. However, work on the reconstructions took longer than anticipated, with Blake in the hands of Portsmouth Dockyard between 1965 and 1969 whilst Tiger was modified by Devonport Dockyard between 1968 and 1972. Delays and an increased workload in the Dockyards resulted in the reconstruction of Lionbeing abandoned and she was placed on the disposal list in 1975. The cost of the conversions proved to be far higher than the original estimates: Blakecost £5.5 million whilst Tiger cost £13.25 million. Blake was sold in 1982 having been laid up in 1980 whilst Tiger survived until 1986.14 Always regarded as a stop-gap in both their roles, these ships were open to criticism on grounds of both cost and manpower. New ships would have been a better answer but a financial constraints meant that second-best had to be accepted.


Blake on 6 May 1969 reconstructed as a helicopter cruiser.

(Crown Copyright)


The first scheme to modernise Eagle was considered in 1955 when the ship had been in service for barely four years. It was extensive, expecting to cost £16.5 million and take 6 years to complete, so it was considered unacceptable. A more austere scheme was worked out which was expected to cost £11 million and take 4 years. The aircraft complement was initially to be 12 NA.39 (Buccaneer), 10 N.139 (Sea Vixen), 12 P.177 (a combined jet/rocket fighter cancelled in 1957, a concept flight-tested in the SR.53), 14 Gannet ASW aircraft and 2 rescue helicopters. In operational service the aircraft carried included Buccaneer strike aircraft, Scimitar and Sea Vixen fighters, and Gannets. This modernisation was approved by the Board of Admiralty in July 1958.

The reconstruction was still extensive. A completely new island was fitted and a fully-angled flight deck (8½°) installed. The 4in armoured deck was removed and replaced with 1½in NC armour, producing a weight saving of 1294 tons whilst changes in the armament saved a further 442 tons. Strengthening the structure cost 605 tons whilst an extra 183 tons of aviation fuel could be carried. The major gain was 892 tons growth allowance to cope with the inevitable alterations and additions to come. The deck was strengthened to enable it to bear a static load of 45,000lbs and for a total landing reaction of 150,000lbs. Two steam catapults were fitted, one initially to be placed on the starboard side having a stroke of 151ft. This was later situated on the port side forward. The second catapult was located on the angled deck and had a stroke of 199ft. Deck blast deflectors and cooling panels were fitted. To handle the increasing weight of aircraft a new crane was provided which had a working load of 35,000lbs with overload of 45,000lbs. Both lifts were upgraded with capacity to accept a working load of 40,000lbs. The arrester gear was also upgraded.

The four forward twin 4.5in mountings were to be replaced, initially by two 6-barrelled Bofors and two twin L70 Bofors; the Bofors L70 were, however, replaced in the specification by Sea Cat close-range anti-aircraft missiles. Other modifications to the close-range anti-aircraft armament included new MRS8 directors to control the 6-barrel Bofors. The radar installations were also substantially upgraded with a Type 984 long-range air warning radar being the principal feature. The communications systems were completely updated and generating capacity was increased by 3000 kW to 8250 kW. Accommodation and air-conditioning were also improved. Originally stowage was to be provided for 283 tons of High Test Peroxide (HTP) in four pure aluminium tanks fitted in the spaces where the forward 4.5in magazines had been located. With the cancellation of the P.177 aircraft this requirement was deleted.


Eagle in 1964, the second fleet carrier to be reconstructed. The Types 984 and 965 radar, modified superstructure, and fully angled deck are notable differences from the ship’s appearance in 1951 when first completed (see Chapter 1). (Royal Naval Museum)

Although the modernisation was expected to provide the best of the fleet carriers when the work was completed, she was not up to the standards that could have been achieved in a new ship. Steam conditions and quantities were lower than needed and the electrical system now being a complicated DC/AC arrangement was barely adequate to satisfy the new demands. Improvements in habitability were limited and increases in wiring and pipework resulted in lower headroom. It was also calculated that had the ship been damaged by conventional weapons then the heel of the ship would have been greater than that expected in a ship of modern design. Nevertheless, it was initially believed that the cost of a new ship would have been two or three times greater than the £11–14 million it was expected to cost reconstructing Eagle over a period of 3½ years, the time being reduced from the earlier 4-year estimate.15

By October 1959 the modernisation was expected to cost £23.5 million and to take 4½ years to complete. Members of the Board of Admiralty expressed grave disquiet that such a large adjustment in the estimate should be found necessary in such a short space of time. The Board considered if there was any acceptable means of reducing the cost but the conclusion reached was that any loss of capability would not be acceptable. However, the sanction of the Treasury and Ministry of Defence were needed and in the meantime the Board directed that there should be no extensive stripping of the armoured deck. This support was forthcoming and the work proceeded, the ship being in the hands of Devonport Dockyard from mid-1959 to May 1964, the cost ultimately reaching £31 million.16

Eagle returned to service for less than 8 years before being paid off in January 1972. As part of a refit in the late 1960s the ship was due to have been modified to enable her to operate Phantoms, but in February 1968 it was decided this would not take place.17She was retained while her erstwhile sister Ark Royal remained in commission, before being finally towed away to the ship-breakers in 1978.

Girdle Ness

The development of the Sea Slug guided missile required the use of a ship for sea trials. Initial studies from 1948 to 1950 called for the conversion of an LST 3 to fulfil the role, with the proposal being considered in some detail. It was however decided that the poor sea-keeping qualities and the short rolling period of the LST meant that it was not the ideal vehicle for the trials. Girdle Ness, a Canadian-built landing craft maintenance ship completed in September 1945, was chosen in December 1950 as both the trial ship and the prototype ‘Type C’ missile ship. As the project progressed it was found that after the ship had performed her role as a trials ship there would be difficulty in accommodating the full war complement. It was therefore decided that she would not become a ‘Type C’ operational warship, with the result that the completed conversion did not incorporate guns, armour protection and other operational features. In March 1951 there were thoughts that the ship could also carry out trials of another new missile codenamed ‘Mopsy’, which was designed to replace the 3in/70 cal. gun, which had yet to go to sea on trials aboard Cumberland. In the event this suggestion soon died.

The Board of Admiralty approved the sketch design in July 1953, the ship being taken in hand at Devonport Dockyard. The superstructure was stripped away and replaced by new upperworks with the guided missile launcher placed forward of the bridge. All the necessary radars, displays and communications equipment were installed and the ship was duly commissioned in July 1956. At this stage some missile handling, testing and control items were not ready, but the ship was capable of firing missiles unguided. Girdle Ness was commissioned for a further series of trials in April 1959 when presumably all the missile systems were operational. A triple launcher was installed for the tests but the production system installed in the ‘County’ class was a twin launcher. She was fitted with a Type 901 radar for missile control and a Type 293 for target-finding. A Type 960 long-range air warning set and Type 982/983 intercept and height-finding radars were also carried. Girdle Ness successfully completed her role and paid off as a guided-missile trials ship in December 1961 after which she served as an accommodation ship for many years.18


Girdle Ness in September 1956. Note the triple Sea Slug launcher, which was not ultimately adopted in the ‘County’ class.


The Radar Picket Destroyers

The need for radar picket destroyers was initially met by converting the four ships of the ‘Weapon’ class. The radar picket was a requirement indicated by war experience which was to be met by the 1947 Fleet Aircraft Direction Escort (FADE) project, which considered a lengthened Daring class destroyer and the conversion of either the cruiser Scylla of the Dido class or the fast minelayer Ariadne. These ideas were followed by the Type 62 frigate project. All were destined to fail. It was to be 1958 before a start was made in converting the ‘Weapon’ class to fulfil the new role. The conversion was not radical and very much an interim measure. The torpedo armament was removed, the space being utilised to install the Type 965 (AKE 1) early warning radar and deckhouses. The main twin 4in armament and anti-submarine mortars were retained, thus keeping an anti-submarine capability.


Scorpion in 1961 as a radar picket, with a Type 965 array and obsolete torpedo armament removed. As reconstructed this ‘Weapon’ class ship carried a Mark X mortar and remained a useful anti-submarine vessel.

(World Ship Society)

Well before the conversion of the ‘Weapon’ class destroyers had commenced, work had started in 1954 to design a fleet picket based on reconstructed 1943 ‘Battle’ class destroyers. Initial ideas were to substitute the single 4.5in Mark V gun mounted immediately aft of the funnel and a set of torpedo tubes with the new radar installation. As an alternative a full modernisation and conversion was to be considered with an extended forecastle as seen in the Type 15 frigates. By March 1955 three schemes were being investigated: Scheme ‘A’ involved a full conversion, reboilering, a new AC electrical system and generators, a revised close-range and anti-submarine armament and an improvement in habitability achieved by the extension of the forecastle. Scheme ‘B’ was less ambitious, with boiler and electrical systems only modified and the forecastle deck extended. Scheme ‘C’ incorporated modifications to the boilers and electrical systems.

By May 1955 it was decided that Scheme ‘A’ would proceed. But in January 1957 when general arrangement drawings had been completed which incorporated the ship being bulged in order to meet stability, strength and buoyancy considerations, Scheme ‘A’ was abandoned and an ‘austerity’ conversion took its place. By July 1958 this scheme was ready to proceed and general arrangement drawings were sent to the Dockyards in February 1959. Four ships were converted: Aisne at Chatham, Agincourt at Portsmouth, Barossa at Devonport and Corunna at Rosyth. The work was scheduled to take between 24 and 28 months, a schedule, which largely seems to have been met.19

The main changes seen were the replacement of the mast by a substantial installation which carried a Type 965 (AKE 2) early warning radar and the Type 277Q height finding radar. The short-range 40mm Bofors and torpedo tubes were removed and replaced by a Sea Cat missile system and two single 20mm guns. The electrical requirements of the new radar and Sea Cat meant that the electrical system had to upgraded with an AC system being installed. The two twin 4.5in mountings with the American Mark 37 director were retained. The class were in service with the fleet for about 8 years, being disposed of between 1970 and 1978.20


Aisne in 1966, a ‘Battle’ class radar picket conversion with Type 965 double aerial.

(Royal Naval Museum)


‘Battle’ class radar picket. The original proposal to convert all eight of the 1943 class produced a very handsome ship, which was unfortunately abandoned on grounds of cost. Note the extended forecastle.

(Drawing by John Roberts from original in NMM ADM 138/860)

Ark Royal

Originally a sister-ship of Eagle, the Ark Royal was laid down in 1942 and finally completed in 1955. There were thoughts about giving her an extensive reconstruction on the lines seen in Eagle but this plan was abandoned. By 1963 the decision had been made to replace the ship with a new aircraft carrier even though she was only 8 years old. The problem was that much of her equipment and structure dated back to the war years and had deteriorated due to age and heavy usage during her operational life. In 1963 there was already a tendency for her equipment to break down and it was concluded that the planned refit over 2 years, which would commence in 1966, would only extend the life of the ship until 1972. If the ship were to run on for a further 2 years until 1974, the 1966 refit would take 3 years against the 2 years planned, additional work being inevitable. The result would be that one extra year of refit would only achieve 2 extra years’ service, a net gain of only a year. One particular problem area was the electrical system. Ark Royal was a DC ship and power was already inadequate for her equipment and duties. The distribution system was described as overloaded and even dangerous. Additional AC generators would have to be fitted, communications needed to be bought up to date, and it was necessary to extend the air conditioning. Habitability would remain poor. The cost at this stage was said to be of the order of £9 million.21

The scope of the refit changed with the cancellation of the new aircraft carrier CVA-01 and aircraft projects such as the P.1154. The ship now benefited from what was described as a ‘special refit and modernisation’ between March 1967 and February 1970 at a cost of £32.5 million. The result was that Ark Royal could now operate the Phantom and Buccaneer Mark II. The catapults and landing gear were improved and an extension added to the island. Two Type 965 search radar systems were carried with a Type 982 for aircraft direction and Type 983 for heightfinding.22

There had been doubts about completing the special refit in the months after the demise of the new aircraft carrier early in 1966 and in March 1969 it seemed that her operational life would be short as the ship was due to deequip in mid-1972. The refit did not always go smoothly, because a shortage of coppersmiths resulted in the pipework running behind schedule. The medical authorities advised that asbestos lagging was dangerous and then the substitute material proved even more toxic in the short term. A substitute for the substitute had to be found! There were then problems with gas turbine-driven generators which meant that electrical output might have to be downgraded. Nevertheless, the preliminary sea trials in December 1969 went well, but by January 1970 vast numbers of defects and deficiencies were said to be showing up, thus vindicating the warnings given 7 years earlier. In the end the ship ran on until December 1978, well beyond her allotted lifespan, being nominally replaced by the newly-built Invincible.23

The retention of Ark Royal was important, for it gave the fleet air cover while she was the sole operational fleet carrier during a period of financial stringency when inflation was rampant, devaluation of the currency a fact of life, and the economy in a severe recession. For all her faults she was a valuable ship.


Ark Royal towards the end of her long service career, with Phantom and Buccaneer aircraft on deck.

(Royal Naval Museum)

1 ADM 138/767: Existing Fleet Carriers Modernisation 1945–1949 (NMM).

2 ADM 1/19161: 1945 Modernisation of Fleet Carriers; ADM 1/19977: 1946–47 Modernisation of existing Fleet Carriers (PRO) and ADM 138/767: Existing Fleet Carriers Modernisation 1945–1949 (NMM). The nature of the argument over closed versus open hangars changed with the advent of nuclear weapons and jet aircraft. See Chapter 4.

3 ADM 138/767: Existing Fleet Carriers Modernisation 1945–1949 (PRO).

4 ADM 138/770: Victorious (NMM), and D K Brown, A Century of Naval Construction. ‘The Developments in Reboilering’ are recorded in ADM 167/143: 1953 Admiralty Board Minutes and Memoranda (PRO). The cost estimates are recorded in ADM 167/144: 1954 Admiralty Board Minutes and Memoranda (PRO). The insidious effects of inflation were a factor in the escalating costs but by no means the dominant influence.

5 ADM 138/806: Implacable Modernisation, and ADM 138/818: Fleet Aircraft Carrier New Design 1952 (NMM).

6 Vickers Archives (Cambridge University Library) and ADM 167/144: 1954 Admiralty Board Minutes and Memoranda (PRO). Weight saving measures are recorded in ADM 167/143: 1953 Admiralty Board Memoranda (PRO). The photo-elasticity technique was introduced to NCRE by J A H Paffett and applied to the side lift structure by K J Rawson. Side lifts proved not to be really compatible with closed hangers and the installation was removed from Ark Royal when the ship was fitted with an angled deck. The Ark Royal side lift served only the upper deck.

7 Conway’s All the World’s Fighting Ships 1947–1995, p499. The Constructor Commander who served in the Hermes in the Falklands War described her as ‘A bloody great steel fort’.

8 The stabilisation trials were recorded in J Bell, ‘Stabilisation Controls and Computation’, Transactions of the Institute of Naval Architects (1957). The author points out that ‘stabiliser’ is a misnomer: they are rolling damping devices. The full power trial with the three-bladed noise reduced propellers was dubious given the state of the ship’s boilers. From memory D K Brown believes that she reached c25kts safely.

9 ADM 167/140: 1951 Admiralty Board Minutes and Memoranda (PRO).

10 Vickers Archives (Cambridge University Library).

11 ADM 138/777: Tiger Class Cruisers (NMM). It was hoped that a Tiger class cruiser could defeat a Soviet Sverdlov class cruiser. The Tiger had the advantage of a faster rate of fire with heavier shells and better cross-level correction (D K Brown).

12 ADM 167/144: 1954 Admiralty Board Minutes and Memoranda (PRO); and ADM 138/777: Tiger Class Cruisers (NMM).

13 Conway’s All the Worlds Fighting Ships 1947–1995, p504. The cost of the cruisers is quoted in Jane’s Fighting Ships 1970–71. There were two designs of Mark XXVI mounting. Of the six in service three had hydraulic drive and three had electric drive. Lion had one of each.

14 ADM 1/28609: 1963 Fleet Requirements Committee: proceedings 1963; and Conway’s All the Worlds Fighting Ships 1947– 1995, p504. The concerns of the War Office at the loss of shore bombardment capability were expressed at a meeting of the Operational Requirements Committee (ORC) held on 16 February 1964. See DEFE 10/457 1963–1964: Minutes of Meetings of ORC (PRO). The Board of Admiralty discussions in October 1963 and January 1964 are recorded in ADM 167/162: 1963 Admiralty Board Minutes, and ADM 167/163: 1964 Admiralty Board Minutes (PRO). The cost of conversion to carry helicopters is quoted in Jane’s Fighting Ships 1974–75. These costs look suspect as quoted, the disparity being so great. The figures for Tiger may include additional overheads.

15 ADM 167/152: 1958 Admiralty Board Memoranda, and ADM 167/153: 1959 Admiralty Board Memoranda (PRO). In the Ship’s Cover ADM 138/866: Aircraft Carrier Eagle, three schemes are recorded in November 1955. Scheme I – all Staff Requirements met; cost £7m over 4 years. Scheme II – as I but interim deck retained; cost £6.5m over 4 years. Scheme III – interim angled deck and existing radar retained; cost £5.75m over 3¼ – 3½ years. Scheme I seems to have been the one adopted but the costings are very different. A double headed Type 984 radar was considered. The weight adjustments are taken from the Legend in the Ship’s Cover. The deletion of the need to provide stowage for HTP was a gain, for this fuel is difficult to maintain, a pollution-free environment being needed. The explosion of a torpedo on the submarine Sidon in 1959 brought home the risk of handling HTP.

16 ADM 167/155:1959 Admiralty Board Memoranda. The final cost of the modernisation is quoted in Jane’s Fighting Ships 1966–67.

17 DEFE 13/952: Ark Royal (PRO). About this time D K Brown was asked why she was not originally designed to operate bigger aircraft. His reply was, ‘You were flying Swordfish when she was designed.’

18 ADM 138/737: Girdle Ness, and ADM 138/789 Guided Weapon Ships 1 (NMM). Jane’s Fighting Ships 1959–60 and 1962–63 describe the ship.

19 ADM 138/860: Destroyers ‘Battle’ Class – Conversion to Fleet Pickets (NMM).

20 Conway’s All the Worlds Fighting Ships 1947–1995, p506, and Norman Friedman, The Post War Naval Revolution. The AKE 2 was double the size of the AKE 1. For implications see problems with weight in ‘Tribal’ class frigates.

21 ADM 1/28639: Aircraft Carrier Programme – date for placing order for replacement of HMS Ark Royal.

22 Conway’s All the Worlds Fighting Ships 1947–1995, p498.

23 DEFE 13/952: Ark Royal gives background on the special refit. The health concerns raised by the medical profession have proved to be well-founded for asbestosis is fatal.

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