This text ruthlessly plundered from Jeremy Olver's Warship site. Researched and © Jeremy Olver.

Leander Class General Purpose Frigate (Type 12 Improved)

The 1951 frigate programme resulted in four types of specialised frigate: anti submarine (Type 12), anti-aircraft (Type 41), aircraft direction (Type 61) and utility (Type 16). However there was a clear requirement for a class of general purpose frigate. A standardised design would not only be cheaper to construct and operate but the multi-rôle capability would make operational deployments easier. This requirement was partly fulfilled by the Tribal Class, although these vessels had insufficient armament and speed to act in an escort role and were consequently employed mainly in the Far East and at foreign stations. Plans to build further Tribal class frigates were abandoned in favour of modifying the Type 12 design.

Design work on updating the Type 12 design began in 1958. Whilst the hull and machinery of the Whitby Class and Rothesay Class Type 12 frigates remained largely unchanged, the superstructure was redesigned as a single block and incorporated a helicopter hanger. Internally air conditioned, the modified vessels would have better living and working conditions than their predecessors and would be more resistant to nuclear and chemical warfare. For example, they were built without portholes. With a standard displacement of 2,450 tons they would measure 37ft in length, 41ft in beam and 18ft in draught. Powered by two Babcock and Wilcox boilers they were designed for a speed of 30kts and a complement of 251. The armament was tailored to suit their general purpose role. They would carry 4.5 inch Mk6 twin mounting while for close range air defence they were designed to carry a Seacat launcher on the hanger roof. Anti submarine defence would consist of a single Mk10 three barrelled Limbo Anti Submarine mortar mounted aft of the flight deck, and the Westland Wasp Helicopter. Design features from the County Class Destroyers were also incorporated including a bridge that provided better visibility and hydraulic power systems to drive the Seacat lifts and various winches. This feature also reduced the manpower needed on deck to operate the Leander Class. The Leander Class design was noted for strong performance in poor weather and heavy seas. This was made possible through twin rudders, twin propellers and non-retractable fin stabilisers.

In 1960 the Admiralty announced that three Rothesay class vessels would be completed to a Leander design and subsequently Weymouth, Fowey and Hastings, were converted whilst under construction and completed as Leander, Ajax and Dido, respectively. A fifth unit of the Salisbury Class, originally laid down as Coventry, was completed as fourth Leander, Penelope. Orders for Aurora, Euryalus and Galatea were placed in 1961 followed by a further three - Arethusa, Naiad and Cleopatra - the following year. Six additional units ordered between autumn 1962 and early 1963 formed a slightly modified second batch, of which the main difference was an improved engine room design with new machinery (Y-136 as opposed to Y-100). The design was revised again resulting in a third batch of ten ships, ordered between 1965 and 1968. These vessels had improved propulsion (Y-160) but more importantly were 43ft in beam, which improved stability and increased internal space. They were correspondingly referred to as ‘Broad Beam Leanders’.

The final Leander Class Frigate, Ariadne, entered service in 1971. The class, now consisting of 26 vessels, was the largest class of major warship built for the Royal Navy since the end of the Second World War. The building programme had lasted thirteen years and provided work for over a dozen shipbuilders. The construction programme was also the last to incorporate Royal Dockyards: HMS Andromeda was the last warship built at Portsmouth Dockyard and HMS Scylla the last built at Devonport Dockyard. The Leander Class bore names of mythological characters from Greek and Roman mythology, last used for Second World War era cruisers, thereby emphasising the frigate’s increasingly important role in the modern Navy. The design was successfully exported overseas. Four vessels were built in UK yards: two for New Zealand and two for Chile, while eleven were built in foreign yards: two for Australia, three for India and six for the Netherlands.

The scale of the building programme and the period it spanned, meant that by the time the last vessel entered service the design was largely outdated, lacking new guided missiles and long range anti submarine equipment. The first seven vessels hadn’t even been completed with Seacat. In order to avoid obsolescence these vessels required the latest equipment and technology. As the first Leander Class vessels approached mid life refits, the 1968 Defence White Paper announced that these vessels would be equipped with the Australian Ikara Anti Submarine system. For this to occur the 4.5 inch gun was removed and replaced with the necessary Ikara equipment. Various electronic equipment, sensors and radar’s were also removed or replaced. These changes resulted in what was effectively an Anti-Submarine specialised frigate. The Ikara conversions were undertaken in two groups: 1A and 1B, so that lessons learnt from the first 1A conversions could be incorporated into the 1B vessels. Most of the conversions took place at Devonport Dockyard although the workload saw Arethusa converted at Portsmouth and Aurora at Chatham. In total eight batch one vessels were converted.

The Batch 2 vessels were similarly redesigned, but not for Ikara. The decline of the Aircraft Carrier and large calibre guns diminished the Navy’s ability to counter the growing Russian surface fleet. To remedy the situation a 1970 statement on defence policy called for the surface fleet’s offensive strike capability to be upgraded. It was therefore decided to fit the Batch 2 Leander Class frigates with the French Exocet surface to surface missile. The 4.5 inch gun was removed and in its place four exocet launchers were added. The limbo mortar was also removed so the flight deck could be extended to accommodate the new Lynx helicopter, which required the hanger to be enlarged slightly. The Lynx was faster than the Wasp and could carry the Sea Skua air to surface missile. 360° air defence was provided by two quadruple Sea Cat launchers: one mounted on the hanger, the other on the forecastle. Two Mk9 Bofor guns were added to the superstructure while 6 torpedo tubes were added to replaced the limbo, three either side of the hanger. The Exocet conversions also took place in two distinct groups: 2A and 2B. Finally, the 1981 Defence Review saw Juno converted into a navigation trials ship, replacing Torquay. Her weapons and radars were removed and accommodation, classrooms and workshops added.

Those responsible for planning the Batch 3 upgrade looked to the new Broadsword Class Type 22 Frigates under construction. They carried both the Seawolf missile system and the Type 2016 sonar. The Batch 3 Leanders had been built with a larger beam and were therefore more accommodating to modernisation. The limbo mortar, Seacat, 4.5 inch gun and all radars were removed. In their place a sextuplet Seawolf missile launcher and four exocet missile launchers were added. As with the previous conversions, most took place at Devonport where the new Frigate Refit Complex (completed 1977 and spanning Number 5,6 and 7 docks - the largest covered dock in Europe) enabled all weather work. However during the Falklands Conflict it meant work on Scylla came to a halt as all attention and effort at Devonport was switched to converting requisitioned merchant vessels. Originally all ten Batch 3 vessels were to undergo this upgrade but the 1981 Defence review cancelled the last five conversions on the grounds of costs. Although this gave the unconverted vessels the advantage of being able to provide naval gunfire support (NGFS), which had proven especially useful in the Falklands, they lacked the modern sophisticated equipment and capabilities of both the converted vessels and the Broadsword Class Type 22 Frigates. As a result they were largely assigned to training duties and early disposal.

Unsurprisingly the twenty six Leander Class Frigates made up the backbone of the Royal Navy in the 1970s and 1980s and had long and full careers, participating in numerous operations, exercises and deployments. They frequently represented the UK contribution to various NATO commitments including Standing Naval force Atlantic and Naval On Call Force Mediterranean (NAVOCFORMED) and hence were an important part of Britain Cold War defence. They also served as guardships at Gibraltar, the West Indies, the Far East and other locations ‘flying the flag’ and providing a credible deterrent.

Several Leander Class Frigates also participated in the Beira Patrol. This was undertaken between 1965 and 1975 and was part of the economic sanctions imposed following Ian Smith’s unilateral declaration of independence. The patrol was designed to prevent oil from South Africa reaching Rhodesia through Beira and other Portuguese ports in Mozambique. The Leander Class also played an active role in the so called ‘Cod Wars’, where they acted as Fishery Protection Vessels and attempted to protect British trawlers. During these operations numerous skirmishes, collisions and rammings occurred with Icelandic Gunboats. Leander Class vessels also undertook the Armilla Patrol on various occasions, and during the height of the Iran-Iraq war the five Seawolf Leanders made frequent visits to the Persian Gulf region on order to protect British shipping passing through the Straits of Hormuz.

Towards the beginning of the 1980s some of the earlier vessels were beginning to show their age, as was their Ikara missile system. John Nott’s notorious 1981 Defence Review placed an increased emphasis on submarines rather than the surface fleet. Hence the Seawolf Conversion of the last five Broad beam Leanders was cancelled whilst as part of a general scale down of the surface fleet some of the older units would be retired early. Bacchante, Naiad, Dido and Achilles were all earmarked to enter the Standby Squadron. However the outbreak of the 1982 Falklands conflict put pay to some of these plans. The Fleet’s hasty deployment to the South Atlantic left several gaps in the Navy’s ability to operational commitments. Consequently, whilst four Leander Class vessels participated in the 1982 Falklands war- Andromeda, Minerva, Argonaut and Penelope- most of the class covered the increased commitments with NATO or in home waters, including some of those ships destined for reserve the previous year.

After fighting in the South Atlantic had ended the five unconverted Broad beam Leanders undertook several Falklands Patrols. For this they were armed with extra 20mm guns and had their pennant numbers painted out. Their future was secured in the 1984 Defence Review which, in the wake of the Falklands, reversed the previous decision to dispose of them early. However, in 1983 Bacchante and Dido became the first Leanders to leave Royal Navy service, having been sold to New Zealand to replace the two ageing Rothesay Class Type 12 Frigates Otago and Taranaki.

During the 1980s a further conversion was carried out on Phoebe, Argonaut, Cleopatra and Sirius. This saw the addition of the Type 2031 towed array sonar which had proved extremely successful during trials on HMS Lowestoft. Batch 1 Leander Arethusa also had this fitted and at the same time her Ikara was replaced by exocet.

By the late 1980s the age of the Leander Class was resulting in mechanical and technical problems, which required constant maintenance to keep the ships fully operational. The Leander Class required excessive manpower to operate compared to the new Duke Class Frigates entering service, and this was at a time when the navy was suffering a manpower shortage. Several Leanders also fell victim to the ‘peace dividend’ that occurred as the Soviet Union collapsed and the Cold War ended. This was highlighted by Tom King’s ‘Options for Change’ Defence Review, which continued the downsizing of the surface fleet.

Most vessels were sold for breaking up or used to test new weapon systems, although some were sold for further service with other navies. The unmodified Batch 3 vessels were particularly attractive to foreign customers- without the sophisticated equipment of their converted sisters, they were less obsolete, less expensive and could be converted more easily for future use. Consequently Diomede and Apollo were sold to Pakistan while Achilles and Ariadne were transferred to Chile. In contrast the remaining Batch One Leanders were more difficult to sell, as their Australian Ikara missile system could only be sold to Commonwealth Nations. Hence most were sunk as targets or broken up.

Two vessels, Aurora and Euryalus, were bought by Devonport Management Ltd (DML) who hoped to refit and resell them to a foreign navy or failing that, use them as a source of spare parts and equipment for other Leanders. However the enterprise proved to be unsuccessful and both vessels were sold for scrap. Increasing health and safety legislation, low scrap metal prices and increasing competition from Asia has seen the decline of shipbreaking in Great Britain. Nevertheless Euryalus and Aurora were broken up at Millom, near Barrow. Other Leanders sold for breaking up were scrapped abroad, mostly in India.

The last Leander Class vessel in Royal Navy service, Scylla, paid off in 1992 and joined the last of her sisterships laid up in Fareham Creek, Portsmouth. Upon the sinking of Sirius in 1998 Scylla has become the last remaining Leander afloat in British waters.

Above: HMS Scylla (F71) armed with Exocet and Seawolf missiles. She is currently the last remaining Leander afloat in British waters..© Crown Copyright.

© Written and researched by Jeremy Olver. First uploaded 15th January 2001. Updated 15th January 2001.