Editing Leander-class frigate (section)

==Midlife major refits==
The entire class were designed for a standard weapons fit when built, with a twin [[QF 4.5-inch Mk I – V naval gun|4.5-inch Mark 6 gun]] mount, [[Seacat (missile)|GWS-22 Seacat]] missile system and [[Limbo (weapon)|Limbo anti-submarine mortar]], though the first seven entered service fitted with two single [[Bofors 40 mm Automatic Gun L/60|40 mm Bofors guns]] on the hangar roof instead of Seacat, with the [[surface to air missile|SAM]] system fitted later.  All but one of the ships had Seacat GWS-22; the exception was ''Naiad'', which had Seacat GWS-20.<ref name=Marriott82>{{citation|pages=82, 84|title=Royal Navy Frigates Since 1945|first1=Leo|last1=Marriott|edition=2nd|publisher=Ian Allan Ltd|year=1990|isbn=0-7110-1915-0}}</ref>  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 (missile)|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 [[Sea Wolf (missile)|Seawolf]] [[surface-to-air missile]] system.
*Gun – retained 4.5-inch gun mount and Seacat missile system.

===Batch 1, Ikara conversion===
[[File:HMS Naiad F39 1982.jpeg|thumb|right|''Naiad'', an Ikara conversion in 1982]]
Eight of the first ten ''Leander''s were given the so-called "Batch 1" or "[[Ikara (missile)|Ikara]]" conversion,<ref name=RNFp87/> which saw the Ikara anti-submarine warfare missile installed in place of the 4.5-inch gun, plus an additional Seacat system,<ref name=Hansard06Jul81c47W/> 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 [[Action Data Automated Weapons System|ADAWS]] needed for Ikara.<ref name=RNFp87/>

{| class="wikitable" 
|+Ikara conversion
|-valign=top
! Pennant
! Name
! Place undertaken
! Started
! Completed
! Cost<ref name=Outturn>[https://api.parliament.uk/historic-hansard/written-answers/1983/dec/14/leander-class-frigate Hansard HC Deb 14 December 1983 vol 50 c473W] The phrase used in Hansard was ''Outturn''.</ref>
|-valign=top
!align=center bgcolor=#E0E0E0 colspan=6 | Batch 1A
|-valign=top
| F109
| [[HMS Leander (F109)|''Leander'']]
| Devonport <ref name=Hansard14Dec83refitdates/><ref name=RNFp87>{{citation|page =87|title=Royal Navy Frigates Since 1945|first1=Leo|last1=Marriott|edition=2|publisher=Ian Allan Ltd|year=1990|isbn=0-7110-1915-0}}<br />Note that Marriott gives slightly different dates than [https://api.parliament.uk/historic-hansard/written-answers/1981/jul/06/frigates-refits Hansard (6 July 1981)] for the completion of the following refits:
{| class="wikitable"
|-
|| ''Leander'' || Dec 1972 (Marriott) || Jan 1973 (Hansard)
|-
||''Ajax'' || Sep 1973 (Marriott) || Feb 1974 (Hansard)
|-
||''Aurora'' || Mar 1976 (Marriott) || Feb 1976 (Hansard)
|-
||''Naiad'' || Jul 1975 (Marriott) || Jun 1975 (Hansard)
|}</ref>
|  | 8 June 1970 <ref name=Hansard14Dec83refitdates>Hansard HC Deb 14 December 1983 vol 50 c473W] Refit dates and costs for ''Leander''-class frigates, 14 December 1983.</ref><ref name=BTInternet>[https://web.archive.org/web/20061212183808/http://www.btinternet.com/~warship/Postwar/Frigates/leander.htm Royal Navy Postwar: Leander Class General Purpose Frigate (Type 12 Improved)]<br />Note that this source says that ''Penelope'' started her Exocet conversion in January 1978, which agrees with [https://api.parliament.uk/historic-hansard/written-answers/1983/dec/14/leander-class-frigate Hansard (14 December 1983)], which says 30 January 1978, but disagrees with [https://api.parliament.uk/historic-hansard/written-answers/1981/jul/06/frigates-refits Hansard (6 July 1981)] recorded that ''Penelope'' started her conversion in June 1978.  It also gives a different start date for ''Arethusa'' – October 1973, whereas [https://api.parliament.uk/historic-hansard/written-answers/1983/dec/14/leander-class-frigate Hansard (14 December 1983)] quotes 10 September 1973 It gives a different start date for ''Andromeda'' – March 1978, whereas Hansard (14 December 1983) quotes 3 January 1978.</ref>
|  | 12 January 1973 <ref name=RNFp87/><ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/>
|  | £7,587,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
| F114
| [[HMS Ajax (F114)|''Ajax'']]
| Devonport <ref name=RNFp87/><ref name=Hansard14Dec83refitdates/>
| 19 October 1970 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/>
| 7 February 1974 <ref name=RNFp87/><ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/>
| £8,269,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
| F18
| [[HMS Galatea (F18)|''Galatea'']]
| Devonport <ref name=RNFp87/><ref name=Hansard14Dec83refitdates/>
| 4 October 1971  <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/>
| 6 September 1974 <ref name=RNFp87/><ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/>
| £9,217,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
!align=center bgcolor=#E0E0E0 colspan=6|Batch 1B
|-valign=top
|  | F10
|  | [[HMS Aurora (F10)|''Aurora'']]
|  | Chatham <ref name=RNFp87/><ref name=Hansard14Dec83refitdates/>
|  | 4 December 1974 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/>
|  | 27 February 1976 <ref name=RNFp87/><ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/>
|  | £15,580,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
|  | F39
|  | [[HMS Naiad (F39)|''Naiad'']]
|  | Devonport <ref name=RNFp87/><ref name=Hansard14Dec83refitdates/>
|  | 15 January 1973 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/>
|  | 20 June 1975 <ref name=RNFp87/><ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/>
|  | £10,410,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
|  | F15
|  | [[HMS Euryalus (F15)|''Euryalus'']]
|  | Devonport <ref name=RNFp87/><ref name=Hansard14Dec83refitdates/>
|  | 7 May 1973 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/>
|  | 12 March 1976 <ref name=RNFp87/><ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/>
|  | £12,127,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
|  | F38
|  | [[HMS Arethusa (F38)|''Arethusa'']]
|  | Portsmouth <ref name=RNFp87/><ref name=Hansard14Dec83refitdates/>
|  | 10 September 1973 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/>
|  | 7 April 1977 <ref name=RNFp87/><ref name=Hansard06Jul81c47W/>
|  | £16,585,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
|  | F104
|  | [[HMS Dido (F104)|''Dido'']]
|  | Devonport <ref name=RNFp87/><ref name=Hansard14Dec83refitdates/>
|  | 7 July 1975 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/>
|  | 27 October 1978 <ref name=RNFp87/><ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/>
|  | £23,006,000 <ref name=Hansard14Dec83refitdates/>
|-
|}

===Batch 2, Seacat/Exocet conversion===
[[File:HMS Phoebe F42 off NorfolkVA 1990.jpeg|thumb|''Phoebe'', an Exocet conversion, in 1990]]
Two of the ''Leander''s with Y-100 machinery, and five out of the six with Y-136 machinery, were given the so-called "Batch 2" or "Exocet" conversion.<ref name=RNFp90/>  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.<ref name=Hansard06Jul81c47W/>

{| class="wikitable" style="font-size:97%;"
|+Exocet / Seacat conversion
|-valign=top
! [[Pennant number|Pennant]]
!  Name
!  Commissioned
!  Place undertaken
!  Started
!  Completed
!  Cost <br />("Outturn")<ref name=Outturn/>
|-valign=top
!align=center bgcolor=#E0E0E0 colspan=8|Batch 2A
|-valign=top
|  F28
| [[HMS Cleopatra (F28)|''Cleopatra'']]
|  4 January 1966 <ref name=Janes1975/>
|  Devonport <ref name=Hansard14Dec83refitdates/><ref name=RNFp90>Marriott, Leo, ''Royal Navy Frigates since 1945'' 2nd ed., pub Ian Allan Ltd, 1990, {{ISBN|0-7110-1915-0}} p. 90.<br />Note that Marriott gives slightly different dates than [https://api.parliament.uk/historic-hansard/written-answers/1981/jul/06/frigates-refits Hansard (6 July 1981)] or [https://api.parliament.uk/historic-hansard/written-answers/1983/dec/14/leander-class-frigate Hansard 14 Dec 1983] for the completion of the following refits:<br />
{| class="wikitable" |- 
||''Cleopatra'' || Nov 1975 (Marriott) ||Dec 1975 (Hansard 6 July 1981)
|- 
||''Sirius'' || Oct 1977 (Marriott) || Feb 1978 (Hansard 6 July 1981) 
|-
||''Minerva'' || Mar 1979 (Marriott) || Apr 1979 (Hansard 6 July 1981)
|-
|| ''Danae'' || Sep 1980 (Marriott) || Apr 1981 (Hansard 6 July 1981) 
|-
|| ''Penelope'' || Mar 1981 (Marriott) || 15 January 1982 (Hansard 14 December 1983) 
|-
|}
In addition, Marriott states that ''Juno's'' Exocet conversion was cancelled in 1984.  However Hansard (14 December 1983) states "''Juno'' is currently being converted at Rosyth to serve as a navigational training ship."</ref>
|  | 23 July 1973 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/>
|  | 19 December 1975 <ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
|  | £13,820,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
| F42
| [[HMS Phoebe (F42)|''Phoebe'']]
| 15 April 1966 <ref name=Janes1975/>
| Devonport <ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
| 5 August 1974 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/>
| 28 April 1977 <ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
|  | £18,204,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
|  | F40
|  | [[HMS Sirius (F40)|''Sirius'']]
|  | 15 June 1966 <ref name=Janes1975/>
|  | Devonport <ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
|  | 10 March 1975 <ref name=BTInternet/>
|  | 10 February 1978 <ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
|  | £21,598,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
|  | F45
|  | [[HMS Minerva (F45)|''Minerva'']]
|  | 14 May 1966 <ref name=Janes1975/>
|  | Chatham <ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
|  | 1 December 1975 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/>
|  | 11 April 1979 <ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
|  | £31,575,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
!align=center bgcolor=#E0E0E0 colspan=8|Batch 2B
|-valign=top
|  | F56
|  | [[HMS Argonaut (F56)|''Argonaut'']]
|  | 17 August 1967 <ref name=Janes1975/>
|  | Devonport <ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
|  | 23 February 1976 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/>
|  | 28 March 1980 <ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
|  | £30,262,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
|  | F47
|  | [[HMS Danae (F47)|''Danae'']]
|  | 7 September 1967 <ref name=Janes1975/>
|  | Devonport <ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
|  | 1 August 1977 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/>
|  | 8 April 1981 <ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
|  | £39,279,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
|  | F127
|  | [[HMS Penelope (F127)|''Penelope'']]
|  | 31 October 1963 <ref name=Janes1963p270/>
|  | Devonport <ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
|  | November 1981 <ref name=Hansard06Jul81c47W>[https://api.parliament.uk/historic-hansard/written-answers/1981/jul/06/frigates-refits Hansard HC Deb 06 July 1981 vol 8 c47W] Question to the Secretary of State for Defence which frigates are now undergoing major refits; at which dockyards; when they commenced; and when they are planned to be completed.</ref><ref name=Hansard14Dec83refitdates/>
|  | 15 January 1982 <ref name=Hansard14Dec83refitdates/><ref name=RNFp90/>
|  | £47,687,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
|  | F52
|  | [[HMS Juno (F52)|''Juno'']]
|  | 18 July 1967 <ref name=Janes1975/>
| colspan=5 align=center| Exocet conversion cancelled.<ref name=RNFp90/>
|-
|}

===Batch 2, navigational training ship conversion===
''Juno'', commissioned 18 July 1967, was converted to serve as a navigational [[training ship]].<ref name=Hansard14Dec83refitdates/> Work at Rosyth<ref name=Hansard14Dec83refitdates/> began in January 1982 and completed in February 1985.<ref name=Hansard14Jul87c437>[https://api.parliament.uk/historic-hansard/written-answers/1987/jul/14/destroyers-and-frigates#S6CV0119P0_19870714_CWA_250 Hansard HC Deb 14 July 1987 vol 119 cc437-40W] Question to the Secretary of State for Defence asking for a list by class the destroyers and frigates presently 438W serving in the Royal Navy showing for each vessel the current age and the dates between which they have undergone major refits, 14 July 1987.</ref> This conversion involved the removal of the Type 965 radar and all of her armament. The flight deck was extended by plating over the mortar well; the STWS 1 torpedo system and two 20 mm guns were installed. ''Juno'' replaced {{HMS|Torquay|F43|6}} in the training role, as well as serving as the trials ship for the Type 2050 sonar.<ref>Marriott, p. 98</ref>

===Batch 3, Seawolf/Exocet conversion===
[[File:HMS Andromeda DN-SC-90-11423.jpg|thumb|right|''Andromeda'', a Seawolf conversion, in 1990]]

The Seawolf conversion gave the broad-beamed ''Leander''s Exocet anti-shipping missiles in place of the 4.5-inch mounting, a [[Sea Wolf (missile)|Seawolf]] missile system in place of Seacat, Sonar 2016, and the ability to operate the Lynx helicopter.<ref name=Hansard06Jul81c47W/>  All the radar systems were removed and replaced by Type 967, 968, 975 and 910 radars.<ref name=MarriottFrigate94>{{citation|page =94|title=Royal Navy Frigates Since 1945|first1=Leo|last1=Marriott|edition=2|publisher=Ian Allan Ltd|year=1990|isbn=0-7110-1915-0}}</ref> Only five of the broad-beamed ''Leander''s 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]].<ref name=RNFp94/>

{| class="wikitable" 
|+Exocet / Seawolf conversion
|-valign=top
! Pennant
! Ship
! Commissioned
! Place undertaken
! Started
! Planned completion
! Actual completion
! Cost<ref name=Outturn/>
|-
!colspan=8|Batch 3A
|-
|-valign=top
| F57
|   [[HMS Andromeda (F57)|''Andromeda'']]
|   2 December 1968 <ref name=Janes1975/>
|   Devonport <ref name=Hansard14Dec83refitdates/><ref name=RNFp94>Marriott, Leo, ''Royal Navy Frigates since 1945'' 2nd ed., pub Ian Allan Ltd, 1990, {{ISBN|0-7110-1915-0}} p. 92.<br />There are also some differences between Marriott and Hansard on the following completion dates:
{| class="wikitable"
|-
||''Andromeda'' ||December 1980 (Marriott) ||February 1981 (Hansard 6 July 1981)
|-
||''Charybdis'' ||August 1982 (Marriott) ||16 July 1982 [https://api.parliament.uk/historic-hansard/written-answers/1983/dec/14/leander-class-frigate (Hansard 14 December 1983)]
|-
||''Hermione''||June 1983 (Marriott) || 8 December 1983 (Hansard 14 December 1983)
|}
</ref>
|  | 3 January 1978  <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/><ref>Marriott, Leo, ''Royal Navy Frigates since 1945'' 2nd ed., pub Ian Allan Ltd, 1990, {{ISBN|0-7110-1915-0}} p. 92 says that she paid off in January 1978.</ref>
|  |
|  | 6 February 1981 <ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/><ref name=RNFp94/>
|  | £59,990,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
| F75
|  | [[HMS Charybdis (F75)|''Charybdis'']] 
|  | 2 June 1969 <ref name=Janes1975/>
|  | Devonport <ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/><ref name=RNFp94/>
|  | 25 June 1979 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/><ref name=Hansard06Jul81c47WBatch3/>
|  | June 1982 <ref name=Hansard06Jul81c47WBatch3>[https://api.parliament.uk/historic-hansard/written-answers/1981/jul/06/frigates-refits Hansard HC Deb 06 July 1981 vol 8 c47W] Question to the Secretary of State for Defence which frigates are now undergoing major refits; at which dockyards; when they commenced; and when they are planned to be completed.<br />[https://api.parliament.uk/historic-hansard/written-answers/1981/nov/30/leander-class-frigates-modernisation#S6CV0014P0_19811130_CWA_169 Hansard HC Deb 30 November 1981 vol 14 c23W] Question to the Secretary of State for Defence asking how many ''Leander''-class frigates are undergoing modernising refits at an estimated unit cost equal to or exceeding the figure of £70 million, 30 November 1981.<br />The answers given on 6 July and 30 November 1981 for the start and forecast completion times for ''Jupiter'', ''Scylla'', ''Charybdis'', and ''Hermione'' are identical, except that on 6 July 1981, it was stated that ''Charybdis'' was forecast to complete in June 1983, and on 30 November, it was stated that she was forecast to complete in June 1982.</ref>
|  | 16 July 1982 <ref name=Hansard14Dec83refitdates/><ref name=RNFp94/>
|  | £61,581,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
| F60
|  | [[HMS Jupiter (F60)|''Jupiter'']] 
|  | 9 August 1969 <ref name=Janes1975/>
|  | Devonport <ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/><ref name=RNFp94/>
|  | 28 January 1980 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/><ref name=Hansard06Jul81c47WBatch3/>
|  | July 1983 <ref name=Hansard06Jul81c47WBatch3/>
|  | 14 October 1983 <ref name=Hansard14Dec83refitdates/><ref name=RNFp94/>
|  | †£68,348,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
| F58
|  | [[HMS Hermione (F58)|''Hermione'']] 
|  | 11 July 1969 <ref name=Janes1975/>
|  | Chatham/Devonport <ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/><ref>Marriott puts ''Hermione''{{'}}s Seawolf conversion at Devonport, whereas [https://api.parliament.uk/historic-hansard/written-answers/1981/jul/06/frigates-refits 6 July 1981, Hansard] puts it at Chatham.</ref>
|  | 14 January 1980 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/><ref name=Hansard06Jul81c47WBatch3/>
|  | January 1983 <ref name=Hansard06Jul81c47WBatch3/>
|  | 8 December 1983 <ref name=Hansard14Dec83refitdates/><ref name=RNFp94/>
|  | †£79,692,000 <ref name=Hansard14Dec83refitdates/>
|-valign=top
| F71
|  | [[HMS Scylla (F71)|''Scylla'']] 
|  | 12 February 1970 <ref name=Janes1975/>
|  | Devonport <ref name=Hansard06Jul81c47W/><ref name=Hansard14Dec83refitdates/><ref name=RNFp94/>
|  | 10 November 1980 <ref name=Hansard14Dec83refitdates/><ref name=BTInternet/><ref name=Hansard06Jul81c47WBatch3/>
|  | September 1983 <ref name=Hansard06Jul81c47WBatch3/>
|  | December 1984 <ref name=RNFp94/>
|  | †£79,278,000 <ref name=Hansard14Dec83refitdates/>
|}
† = Latest estimate as at 14 December 1983.<ref name=Hansard14Dec83refitdates/>

===Batch 2 TA & Batch 1B – towed array conversions===
[[File:HMS Argonaut F56 in 1995.jpg|thumb|right|''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&nbsp;... This includes the new passive towed array system that we hope to introduce into service next year."<ref name=Hansard22Jul81c326>{{cite web |url=https://api.parliament.uk/historic-hansard/commons/1981/jul/22/royall-navy |work=[[Hansard|Parliamentary Debates (Hansard)]] |title=Hansard HC Deb vol 9 cc326-409 Debate on the Royal Navy |date=22 July 1981}}</ref>

{{HMS|Matapan|D43|6}} and {{HMS|Lowestoft|F103|6}} were used for testing prototypes in 1978–1981.<ref name=BDFp302>{{cite book |last=Friedman |first=Norman |title=British Destroyers and Frigates, the Second World War and After |publisher=Seaforth |year=2006 |isbn=978-1-84832-015-4 |page=302}}</ref> It was planned to install them on [[Rothesay-class frigate|''Rothesay'' conversions]], but this was not possible due to industrial strikes.<ref name=BDFp302/>  Scheduling then made it easier to fit them onboard four of the Batch II ''Leander''s.  "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 ''Leander''s, but the latter fell foul of the [[John Nott|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."<ref name=BDFp302/>

[[Julian Oswald|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."<ref>Defence Committee, sixth report, ''The Royal Navy's Surface Fleet: Current Issues –  report, together with the proceedings of the committee, minutes of evidence and memoranda'', pub HMSO, 21 June 1989, minutes of evidence pp.&nbsp;12–13.</ref>

In general, "as a ship gets older it tends to get noisier – the hull and also the propulsion system".<ref>Defence Committee, sixth report, ''The Royal Navy's Surface Fleet: Current Issues –  report, together with the proceedings of the committee, minutes of evidence and memoranda'', pub HMSO, 21 June 1989, minutes of evidence p. 3, remarks by former naval officer [[Jonathan Sayeed|Jonathan Sayeed MP]].</ref> 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 ''Leander''s 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."<ref name=HansardDC21Jun89p3>Defence Committee, sixth report, ''The Royal Navy's Surface Fleet: Current Issues –  report, together with the proceedings of the committee, minutes of evidence and memoranda'', pub HMSO, 21 June 1989, minutes of evidence p. 3.</ref> Captain [[Geoffrey Biggs]] said "the ''Leander''s 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."<ref name=HansardDC21Jun89p3/>

Five ships were converted to use Waverley Type 2031(I) towed array (passive search very low frequency).  They were as follows:<ref>Sharpe, Richard ''Jane's Fighting Ships 1988–89'', pub Jane's Publishing Company Ltd, 1988, {{ISBN|978-0-7106-0858-1}}, page 660 lists five ships as having Type 2031Z towed arrays: ''Arethusa'', ''Cleopatra'', ''Sirius'', ''Phoebe'', and ''Argonaut''.  The last four were described by Jane's as "Batch 2TA".<br /> Defence Committee, sixth report, ''The Royal Navy's Surface Fleet: Current Issues –  report, together with the proceedings of the committee, minutes of evidence and memoranda'', pub HMSO, 21 June 1989, page xviii lists four Exocet ''Leander''s described as Batch 2A: ''Cleopatra'', ''Sirius'', ''Phoebe'', and ''Argonaut''.  "Batch 2A are fitted with towed array sonar."</ref>
{| class="wikitable"
|-
|+Refit when towed array fitted<ref name=Janes1975/><ref name=TArefitVarious>Marriott ''Royal Navy Frigates since 1945'' second edition, page 98 lists which year the ''Leander''s completed the refits in which the towed array was fitted. Friedman ''British Destroyers and Frigates, the Second World War and After'' 2006, p. 302 says that the prototype Type 2031 was installed on ''Cleopatra'', the conversion beginning in 1980, and that ''Arethusa''{{'}}s towed array was fitted in 1985.<br />[https://api.parliament.uk/historic-hansard/commons/1981/jul/22/royall-navy Hansard (22 July 1981)] made it clear that towed-arrays were not in service in 1981, but that it was intended to introduce them into service in 1982.[https://api.parliament.uk/historic-hansard/written-answers/1987/jul/14/destroyers-and-frigates#S6CV0119P0_19870714_CWA_250 Hansard HC Deb 14 July 1987 vol 119 cc437-40W] contains a list of all the refits by the ''Leander''s up to 14 July 1987.</ref>
|-
|-valign=top
!  [[Pennant number|Pennant]]
! Name
!  Commissioned
! Started 
! Completed 
|-valign=top
!align=center bgcolor=#E0E0E0 colspan=8|Batch 2A Exocet ''Leander'' (Batch 2TA)
|-valign=top
|  | F42
|  | [[HMS Phoebe (F42)|''Phoebe'']]
|  | 15 April 1966 
|  | February 1981 
|  | July 1982 
|-valign=top
|  | F28
|  | [[HMS Cleopatra (F28)|''Cleopatra'']]
|  | 4 January 1966 
|  | January 1982 
|  | April 1983 
|-valign=top
|  | F56
|  | [[HMS Argonaut (F56)|''Argonaut'']]
|  | 17 August 1967 
|  | August 1982 
|  | November 1983 
|-valign=top
|  | F40
|  | [[HMS Sirius (F40)|''Sirius'']]
|  | 15 June 1966 
|  | April 1985 
|  | December 1985 
|-valign=top
!align=center bgcolor=#E0E0E0 colspan=8|Batch 1B Ikara ''Leander''
|-valign=top
|  | F38
|  | [[HMS Arethusa (F38)|''Arethusa'']]
|  | 24 November 1965 
|  | May 1985 
|  | February 1986 
|-
|}