HMS Apollo, 1976
Class overview
Name	Leander class
Operators	Royal Navy  Indian Navy  Royal New Zealand Navy  Chilean Navy  Royal Netherlands Navy  Pakistan Navy  Ecuadorian Navy  Indonesian Navy
Preceded by	Rothesay class Salisbury class Leopard class Tribal class
Succeeded by	Type 21 frigate
Subclasses	Condell class River class Nilgiri class Van Speijk class
Built	1959-1973
In commission	1963–1993 (Royal Navy)
Completed	26
Retired	26 (3 as artificial reefs, 2 as targets)
General characteristics
Type	Frigate
Displacement	2,350 tons standard, broad-beam 2,500 tons (later 2,790 tons) standard 2,860 tons full load, broad-beam 2,962 tons (later 3,300 tons) full load
Length	113.4 metres (372 ft)
Beam	12.5 metres (41 ft), broad-beamed 13.1 metres (43 ft)
Draught	4.5 metres (15 ft) normal, 5.5 metres (18 ft) deep, broad-beamed 5.5 metres (18 ft) (later 5.8 metres (19 ft)) deep
Propulsion	2 Babcock & Wilcox oil-fired boilers, geared steam turbines, 22,370 kilowatts (30,000 hp), 2 shafts
Speed	27 knots (50 km/h; 31 mph)
Range	7,400 kilometres (4,600 mi; 4,000 nmi) at 15 knots (28 km/h; 17 mph)
Complement	260
Sensors and processing systems	Radar: Type 965 (air warning radar removed during the Ikara conversion), Type 992 Q, Type 903, Type 974/978 Sonar: Type 162, 184, 199, & later Type 2031 and Type 2016 sonar
Armament	Initial: 2 × 4.5-inch guns (1 × twin mounting Mk6) 1 × Seacat surface-to-air missile launcher 2 × 20mm guns (single mountings) 2 × 40mm Mk VII Bofors (single mountings) initially in first 7 instead of Seacat & 20mm guns 1 × ASW Limbo mortar Batch 1 - Ikara: 1 × Ikara Anti-submarine missile Launcher 2 × Seacat surface-to-air missile launchers 2 × 40mm guns - single mountings 2 × triple 324 mm (12.75) STWS-1 tubes for Mk 46 and Stingray ASW torpedoes 1 × Limbo ASW Mortar Batch 2 - Exocet/Seacat: 4 × MM.38 Exocet anti-ship missile launchers 3 × Seacat surface-to-air missile launchers 2 × 40mm guns - single mountings 2 × triple 324 mm (12.75 inch) STWS-1 tubes for Mk 46 and Stingray ASW torpedoes Batch 3 - Exocet/Seawolf: 4 × MM.38 Exocet anti-ship missile launchers 1 × sextuple GWS.25 launcher with 30 Sea Wolf SAMs 2 × 20mm AA guns 2 × triple 324 mm (12.75) STWS-1 tubes for Mk 46 and Stingray ASW torpedoes
Aircraft carried	Initial and Batch 1: 1 × Westland Wasp ASW helicopter Batch 2 and Batch 3: 1 × Westland Lynx HAS.Mk 2 ASW helicopter

The Leander-class, or Type 12I (Improved) frigates,^[1][2][3] comprising twenty-six vessels, was among the most numerous and long-lived classes of frigate in the Royal Navy's modern history. The class was built in three batches between 1959 and 1973. It had an unusually high public profile, due to the popular BBC television drama series Warship. The Leander silhouette became synonymous with the Royal Navy through the 1960s until the 1980s.

The Leander design or derivatives of it were built for other navies:

• Royal New Zealand Navy as the Leander class
• Chilean Navy: Condell class
• Royal Australian Navy: River class
• Indian Navy: Nilgiri class
• Royal Netherlands Navy: Van Speijk class

Design

The policy adopted by the Royal Navy during the 1950s of acquiring separate types of frigates designed for specialised roles (i.e. anti-submarine, anti-aircraft and aircraft direction) had proved unsatisfactory. Although the designs themselves had proved successful, the lack of standardisation between the different classes led to increased costs during construction and also in maintenance once the ships became operational. Furthermore, it was not always possible to have the ships with the required capabilities available for a specific task. The first move towards creating a truly general-purpose frigate came with the Type 81 Tribal class which was initially ordered in 1956. The 24-knot speed of the Tribals was considered the maximum possible for tracking submarines with the new medium-range sonars,^[4] entering service. The type 81 gas turbine saw the frigates underway quickly, without taking hours flashing up steam turbines, and the provision of a helicopter for long-range attack were considered essential in the nuclear age. These ships were mainly intended to operate in the tropics but lacked the speed and armament required for the priority fleet carrier escort role East of Suez, where fast radar picket capability was important, as much as anti-submarine capability. So the new frigates would combine the roles of the T12 and T61. The fully air-conditioned Royal New Zealand Navy Rothesay class variant, HMNZS Otago, which gave all the crew a bunk and cafeteria messing^[5] and a RNZN commissioned design study for a more fully capable Type 12 frigate, which also assessed whether the Type 12 could carry 2 of the larger Wessex AS helicopters, was used as the basis of the RN Leander Improved Type 12 design.^[6]

On 7 March 1960, the Civil Lord of the Admiralty C. Ian Orr-Ewing stated that the "Type 12 Whitby-class anti-submarine frigates are proving particularly successful ... and we have decided to exploit their good qualities in an improved and more versatile ship. This improved Type 12 will be known as the Leander class. The hull and steam turbine machinery will be substantially the same as for the Whitbys. The main new features planned are a long-range air warning radar, the Seacat anti-aircraft guided missile, improved anti-submarine detection equipment and a light-weight helicopter armed with homing torpedoes. We shall also introduce air conditioning and better living conditions."^[7] The 1963 edition of Jane's Fighting Ships described it as a "mainly anti-submarine but flexible and all-purpose type".^[8]

The Leander class have the same hull and substantially the same steam turbine machinery as the Whitby class, but are a revised and advanced design and will fulfil a composite anti-submarine, anti-aircraft and air direction role. The 40mm guns will eventually be replaced by Seacat ship-to-air launchers. The ships are equipped with VDS (Variable Depth Sonar), formerly known as dipping asdic.

— Jane's Fighting Ships, ^[8]

The difference between the Leanders (Type 12I) and the Whitbys (Type 12) was most obviously that the stepped quarterdeck of the Type 12 had been done away with, resulting in a flush deck, with the exception of the raised forecastle. The superstructure had been combined into a single block amidships and a new bridge design gave improved visibility. A hangar and flight deck were provided aft for the Westland Wasp light anti-submarine helicopter, which was still at the prototype stage when the first ships were ordered. The ship was air conditioned throughout and there were no portholes in order to improve nuclear, biological and chemical defence. The ships were all given names which had previously been given to Royal Navy cruisers, mostly of characters from classical mythology, the exceptions being Cleopatra and Sirius.^[9]

The Y160 boiler variant used on the Batch 3 Leanders (such as Jupiter) also incorporated steam atomisation equipment on the fuel supply so the diesel fuel entering the boilers via the three main burners was atomised into a fine spray for better flame efficiency. Some ships with Y100 Boilers were also converted to steam atomisation, HMS Cleopatra being one of them. The superheat temperature of the Y160 was controlled manually by the boiler room petty officer of the watch between 750–850 °F (399–454 °C) and the steam supplied to the main turbines was at a pressure of 550 psi (3,800 kPa). The Leander-class frigates did have Babcock & Wilcox boilers but of a more conventional two-drum design, one water drum and one steam drum, much like a Yarrow boiler without the second water drum. The water drum was offset to one side and below the furnace and steam drum. The two boilers fitted were 'handed' with the water drum inboard on both. Many Leanders had six-burner furnaces (known as Five and a Half Boilers) and the output was varied by altering the number of burners in use.

Profile of HMNZS Canterbury as she appeared at the time of commissioning. Note the 40 mm Bofors guns in place of Seacat missiles.

Aerial view of HMS Penelope in 1970, showing the original layout of the class before conversion.

Construction programme

Midlife major refits

The entire class were designed for a standard weapons fit when built, with a twin 4.5-inch Mark 6 gun mount, GWS-22 Seacat missile system and Limbo anti-submarine mortar, though the first seven entered service fitted with two single 40 mm Bofors guns on the hangar roof instead of Seacat, with the SAM system fitted later. All but one of the ships had Seacat GWS-22; the exception was Naiad, which had Seacat GWS-20.^[24] However, advances in weapons systems led to a number of different conversions being undertaken on various members of the class. This saw the class grouped into four broad batches:

• Ikara - installation of the Ikara ASW missile system in place of the 4.5-inch gun mount, plus an additional Seacat missile system.
• Exocet/Seacat - installation of Exocet anti-ship missile system in place of 4.5-inch gun mount, plus two additional Seacat missile systems.
• Exocet/Seawolf - installation of Exocet anti-ship missile system in place of 4.5-inch gun mount; replacement of Seacat with single GWS-25 Seawolf surface-to-air missile system.
• Gun - retained 4.5-inch gun mount and Seacat missile system.

Batch 1, Ikara conversion

Naiad, an Ikara conversion in 1982

Eight of the first ten Leanders were given the so-called "Batch 1" or "Ikara" conversion,^[2] which saw the Ikara anti-submarine warfare missile installed in place of the 4.5-inch gun, plus an additional Seacat system,^[25] and the removal of the Type 965 radar and its AKE(1) aerial. The internal space previously used by the Type 965 was used for the ADAWS needed for Ikara.^[2]

Ikara conversion

Pennant	Name	Place undertaken	Started	Completed	Cost[26]
Batch 1A
F109	Leander	Devonport [27][2]	8 June 1970 [27][28]	12 January 1973 [2][25][27]	£7,587,000 [27]
F114	Ajax	Devonport [2][27]	19 October 1970 [27][28]	7 February 1974 [2][25][27]	£8,269,000 [27]
F18	Galatea	Devonport [2][27]	4 October 1971 [27][28]	6 September 1974 [2][25][27]	£9,217,000 [27]
Batch 1B
F10	Aurora	Chatham [2][27]	4 December 1974 [27][28]	27 February 1976 [2][25][27]	£15,580,000 [27]
F39	Naiad	Devonport [2][27]	15 January 1973 [27][28]	20 June 1975 [2][25][27]	£10,410,000 [27]
F15	Euryalus	Devonport [2][27]	7 May 1973 [27][28]	12 March 1976 [2][25][27]	£12,127,000 [27]
F38	Arethusa	Portsmouth [2][27]	10 September 1973 [27][28]	7 April 1977 [2][25]	£16,585,000 [27]
F104	Dido	Devonport [2][27]	7 July 1975 [27][28]	27 October 1978 [2][25][27]	£23,006,000 [27]

Batch 2, Seacat/Exocet conversion

Phoebe, an Exocet conversion, in 1990

Two of the Leanders with Y-100 machinery, and five out of the six with Y-136 machinery, were given the so-called "Batch 2" or "Exocet" conversion.^[29] This conversion gave them Exocet anti-shipping missiles in place of the 4.5-inch gun mount, 2 additional Seacat systems, and the ability to operate the Lynx helicopter.^[25]

Exocet / Seacat conversion

Pennant	Name	Commissioned	Place undertaken	Started	Completed	Cost ("Outturn")[26]
Batch 2A
F28	Cleopatra	4 January 1966 [11]	Devonport [27][29]	23 July 1973 [27][28]	19 December 1975 [25][27][29]	£13,820,000 [27]
F42	Phoebe	15 April 1966 [11]	Devonport [27][29]	5 August 1974 [27][28]	28 April 1977 [25][27][29]	£18,204,000 [27]
F40	Sirius	15 June 1966 [11]	Devonport [27][29]	10 March 1975 [28]	10 February 1978 [25][27][29]	£21,598,000 [27]
F45	Minerva	14 May 1966 [11]	Chatham [27][29]	1 December 1975 [27][28]	11 April 1979 [25][27][29]	£31,575,000 [27]
Batch 2B
F56	Argonaut	17 August 1967 [11]	Devonport [27][29]	23 February 1976 [27][28]	28 March 1980 [25][27][29]	£30,262,000 [27]
F47	Danae	7 September 1967 [11]	Devonport [27][29]	1 August 1977 [27][28]	8 April 1981 [25][27][29]	£39,279,000 [27]
F127	Penelope	31 October 1963 [8]	Devonport [25][27][29]	November 1981 [25][27]	15 January 1982 [27][29]	£47,687,000 [27]
F52	Juno	18 July 1967 [11]	Exocet conversion cancelled.[29]

Batch 3, Seawolf/Exocet conversion

Andromeda, a Seawolf conversion, in 1990

The Seawolf conversion gave the broad-beamed Leanders Exocet anti-shipping missiles in place of the 4.5-inch mounting, a Seawolf missile system in place of Seacat, Sonar 2016, and the ability to operate the Lynx helicopter.^[25] All the radar systems were removed and replaced by Type 967, 968, 1006 and 910 radars.^[32] Only five of the broad-beamed Leanders were converted to carry Seawolf due to costs (£70 million for each refit) and, as a lesser consideration, to retain some ships capable of naval gunfire support.^[33]

Exocet / Seawolf conversion

Pennant	Ship	Commissioned	Place undertaken	Started	Planned completion	Actual completion	Cost[26]
Batch 3A
F57	Andromeda	2 December 1968 [11]	Devonport [27][33]	3 January 1978 [27][28][34]		6 February 1981 [25][27][33]	£59,990,000 [27]
F75	Charybdis	2 June 1969 [11]	Devonport [25][27][33]	25 June 1979 [27][28][35]	June 1982 [35]	16 July 1982 [27][33]	£61,581,000 [27]
F60	Jupiter	9 August 1969 [11]	Devonport [25][27][33]	28 January 1980 [27][28][35]	July 1983 [35]	14 October 1983 [27][33]	†£68,348,000 [27]
F58	Hermione	11 July 1969 [11]	Chatham/Devonport [25][27][36]	14 January 1980 [27][28][35]	January 1983 [35]	8 December 1983 [27][33]	†£79,692,000 [27]
F71	Scylla	12 February 1970 [11]	Devonport [25][27][33]	10 November 1980 [27][28][35]	September 1983 [35]	December 1984 [33]	†£79,278,000 [27]

† = Latest estimate as at 14 December 1983.^[27]

Batch 2 TA & Batch 1B - towed array conversions

Argonaut, a batch 2 Exocet conversion fitted with a towed array, in 1985. Note the platform at the stern added in the towed array conversion in 1982–1983.

In 1981 the Admiralty said that they intended to devote "substantial resources to improving the effectiveness of the sensors and anti-submarine weapons ... This includes the new passive towed array system that we hope to introduce into service next year."^[37]

The former destroyer Matapan and the frigate Lowestoft were used for testing prototypes in 1978–1981.^[38] It was planned to install them on Rothesay conversions, but this was not possible due to industrial strikes.^[38] Scheduling then made it easier to fit them onboard four of the Batch II Leanders. "Compensation for the additional 70 tons of top weight included lowering the Exocet launchers. This interesting quartet was to have been followed by five Batch III Leanders, but the latter fell foul of the Nott cancellations. A fifth Leander, the Ikara-carrying HMS Arethusa, was fitted with a towed array in 1985, the year the towed-array trials ship Lowestoft was withdrawn from service."^[38]

Admiral Sir Julian Oswald said to the Defence Committee in 1989, "in order to capitalise on the really very exciting and important development of towed arrays, we had to get them to sea as soon as we could. The only sensible, cost-effective option open to us was to take some relatively older ships - the Leanders - and convert them quickly to the towed array. We have done that with great success, and the peacetime patrols have achieved some remarkable results, but there has been a price to pay because of the age of those ships."^[39]

In general, "as a ship gets older it tends to get noisier - the hull and also the propulsion system".^[40] At the same Defence Committee meeting, Oswald spoke "to counter the presumption that older ships get noisier. That is not necessarily true and it is not true, in my experience, in the case of the Leanders because understanding of ship-generated noise is improving all the time and our techniques for countering it are improving - our noise monitoring and so on - so, despite the fact that these ships are getting older, they are in many cases managing to improve their performance with regard to ship noise."^[41] Captain Geoffrey Biggs said "the Leanders are remarkably quiet in operation and our experience has been that they have made excellent towed-array platforms despite the rather short notice of actually getting the towed-array programme together to start with. They actually perform very well."^[41]

Five ships were converted to use Waverley Type 2031(I) towed array (passive search very low frequency). They were as follows:^[42]

Refit when towed array fitted^[11][43]

Pennant	Name	Commissioned	Started	Completed
Batch 2A Exocet Leander (Batch 2TA)
F42	Phoebe	15 April 1966	February 1981	July 1982
F28	Cleopatra	4 January 1966	January 1982	April 1983
F56	Argonaut	17 August 1967	August 1982	November 1983
F40	Sirius	15 June 1966	April 1985	December 1985
Batch 1B Ikara Leander
F38	Arethusa	24 November 1965	May 1985	February 1986

Royal Navy service

During their lengthy service with the Royal Navy Leanders were employed during the Indonesia–Malaysia confrontation in 1963-1966. The 1973 and 1975-1976 Cod Wars in the latter of which HMS Diomede suffered severe damage with a 30 feet gash in its hull after being rammed by an Icelandic Coast Guard gunboat. The frigates with their thin hulls being much less suited to this duty than the later offshore patrol vessels.

Four members of the class saw action during the 1982 Falklands War, three Batch Two conversions, HMS Argonaut, HMS Minerva and HMS Penelope ^[44] Argonaut experienced 15 air attacks in San Carlos Sound and was hit by a number of bombs and cannon fire; it was stranded for six days, with two bombs lodged in the forward Seacat magazine and boiler room.^[44] The first Seawolf conversion HMS Andromeda, was one of only three Seawolf fitted frigates available with the Royal Navy's newest missile in the war and served during the war as the critical "goalkeeper"- the last line of defence for the carrier HMS Invincible during the war.^[45] The five unconverted, gun-armed, broad-beam Leanders, arrived in the war zone in the last week of the conflict and immediately after it to serve with the post-war task force led by the brand new carrier HMS Illustrious. An Argentine naval dive team planned to place limpet mines on HMS Ariadne at Gibraltar during the conflict (Operation Algeciras). The last Leander commissioned in 1973, like the two built for Chile, carried special electronic warfare systems, for countering Exocet missiles, and the Argentine services may have anticipated the Ariadne was scheduled for service in the Total Exclusion Zone, which in fact did not happen until after the end of the war.

The ships performed excellently in Royal Navy service, with relatively low noise levels giving the 2031(I) towed sonar a range of more than 100 miles, better than that of the more advanced 2031(Z) sonar when fitted in the Type 22 frigates. However, all Leanders in Royal Navy service were decommissioned by the early 1990s due to the ships' ageing design and the high number of crew. Scylla was sunk on 27 March 2004 as an artificial reef off Cornwall, eleven years after her decommissioning in 1993.^[46]

Overseas service

Leander-class frigates were also successfully exported to serve in the Royal New Zealand Navy and Chilean Navy; in the latter they were designated as the Condell class. Further frigates were modelled on the Leander-class frigates and were built under licence in Australia as the River class for the Royal Australian Navy, India as the Nilgiri class and the Netherlands as the Van Speijk class. Royal Navy ships were sold to the navies of Chile, Ecuador, New Zealand (Bacchante becoming HMNZS Wellington and Dido becoming HMNZS Southland), India and Pakistan.

Starting in 1986, the six Van Speijk-class ships were sold to the Indonesian Navy and renamed the Ahmad Yani class, five of which are still in service.^{[Note 1]} Pakistan decommissioned the last of its Leander-class frigates, Zulfiqar, in January 2007,^[52] India decommissioned her last Leander class on 24 May 2012.^[53]

HMNZS Canterbury, the last steam-turbine driven Leander-class frigate in the Royal New Zealand Navy, was decommissioned in Auckland on 31 March 2005 after 33 years operational service. In 2006 it was announced that the ship was to be sunk as a dive attraction in the Bay of Islands, and this was carried out on 3 November 2007 at Deep Water Cove. She lies near her sister ship HMNZS Waikato.^[54]

Fate

Royal Navy

See also

• List of naval ship classes in service
• Whitby-class frigate, the original Type 12 frigate.
• Rothesay-class frigate, the follow-on Type 12M frigate.
• Warship, a BBC television drama series.

Notes

References

Bibliography

• Allanway, Jim (1995) Leander Class Frigates, H M Stationery Office, ISBN 978-0117724587
• Colledge, J J; Warlow, Ben (2010). Ships Of The Royal Navy: A Complete Record of all Fighting Ships of the Royal Navy from the 15th Century to the Present. Casemate. ISBN 978-1935149071.
• Jackson, Robert (2006) The Encyclopedia of Warships, From World War Two to the Present Day, Grange Books Ltd, ISBN 978-1840139099
• Marriott, Leo (1990), Royal Navy Frigates Since 1945, Second Edition, Ian Allan Ltd (Surrey, UK), ISBN 0-7110-1915-0
• Meyer C J (1984) Modern Combat Ships 1: Leander Class, Littlehampton Book Services Ltd, ISBN 978-0711013858
• Osbourne, Richard and Sowdon, David (1991), Leander Class Frigates: History of Their Design and Development, 1958-90, World Ship Society, ISBN 978-0905617565
• Purvis, M K, Post War RN Frigate and Guided Missile Destroyer Design 1944-1969, Transactions, Royal Institution of Naval Architects (RINA), 1974

External links

Wikimedia Commons has media related to Leander class frigates.

• Archived comprehensive website on the design and history of the Leander class and related frigate designs
• Leander (Type 12) class frigate website
• Hazegray.org on the Leander class
• An unofficial Leander Class Frigate Site
• British Film Institute site on Warship
• Royal Navy leaflet on Warship, from the HMS Phoebe Association website
• Comments on Warship by series Director Michael Briant
• Webpage (at Home > Scriptwriting > Warship) about Michael J Bird's scripts for Warship
• HMS Phoebe Association website
• HMS Danae website (all commissions)
• HMS Danae website (first commission)
• HMS Dido Association website Archived 5 May 2007 at the Wayback Machine
• HMS Jupiter Association website
• HMS Hermione Association website Archived 8 December 2006 at the Wayback Machine
• HMS Naiad Association website ("the leander class frigate")
• Postwar Frigates website, retrieved 2010-10-12