Editing Type 12 frigate

{{Short description|Classes of ship}}
'''Type 12 frigate''' refers to several ship classes, most commonly the three [[ship class]]es of the [[Royal Navy]] designed during the 1950s and constructed during the 1960s.
* The first Type 12 [[frigate]]s, designed as convoy escorts, were later named the {{sclass|Whitby|frigate|4}}. Six operated in the Royal Navy, with one loaned to the [[Royal New Zealand Navy]], and two built for the [[Indian Navy]].
* The design of the Type 12 Modified ('''Type 12M''') or {{sclass|Rothesay|frigate|4}} was optimised towards anti-submarine warfare and fleet escort duties, and fitted with the [[Sea Cat missile]] system. Nine were built for the Royal Navy, two for the Royal New Zealand Navy, and three (as the 'President class') for the [[South African Navy]].
* The third class, designed as an all-purpose warship, was known as the Type 12 Improved ('''Type 12I''') or the {{sclass|Leander|frigate|4}}. The class was made up of three 'batches'; the main differences between each batch being variations in propulsion machinery and weapons outfit. 26 were built for the Royal Navy, some of which later saw service in the navies of Chile, Ecuador, New Zealand, and Pakistan.

The Type 12 designation is sometimes used to refer to warship classes based on the Type 12 design, but constructed or operated by other naval forces. Some of these are still in service as of 2009:
* The {{sclass|Condell|frigate|2}}s of the [[Chilean Navy]]. Based on the ''Leander'' class, this class consisted of four ships, two purpose-built, and two former Royal Navy ''Leander''s.
* The {{sclass2|River|destroyer escort|2}}s of the [[Royal Australian Navy]]. Six were constructed: two to the ''Rothesay'' design, two to the same design but modified to carry a variable-depth sonar and an [[Ikara missile]] system (which was retrofitted to the first two), and two to an Australian-designed ''Leander'' variant.
* The {{sclass|Nilgiri|frigate|2||1972}}s of the [[Indian Navy]]. Six were constructed to an updated design based on the ''Leander''s.
* The {{sclass|Godavari|frigate|5}} and {{sclass|Brahmaputra|frigate|2}}s of the Indian Navy. An enlarged ''Nilgiri'' design was used as the basis for six ships (three of each class), with the weapons outfit the main difference between them.
* The {{sclass|Van Speijk|frigate|2}}s of the [[Royal Netherlands Navy]]. Based on the ''Leander'' design but with Dutch radars, six ships were built. All six were later transferred to the [[Indonesian Navy]] and become ''Ahmad Yani''-class frigate. All of them are renamed with Indonesian National Heroes.

==References==
* Marriott,Leo, 'Royal Navy Frigates Since 1945', Second Edition, {{ISBN|0-7110-1915-0}}, Published by Ian Allan Ltd (Surrey, UK), 1990
* Purvis,M.K.,  'Post War RN Frigate and Guided Missile Destroyer Design 1944-1969',  Transactions,  Royal Institution of Naval Architects (RINA),  1974
* {{cite book |last=Jeremy |first=John C. |editor=Stevens, David |editor2= Reeve, John |title=The Navy and the Nation: the influence of the Navy on modern Australia |url=https://archive.org/details/navynationinflue00stev |url-access=limited |year=2005 |publisher=Allen & Unwin |location=Crows Nest, NSW |isbn=1-74114-200-8 |oclc=67872922 |chapter=Australian shipbuilding and the impact of World War II |pages=[https://archive.org/details/navynationinflue00stev/page/n221 196]–8}}

==External links==
* [https://web.archive.org/web/20090326210259/http://middle-watch.com/index.html Comprehensive website on the design and history of the Leander class and related frigate designs]

[[Category:Frigate classes]]