The Fremantle-class patrol boats were coastal patrol vessels operated by the Royal Australian Navy (RAN) from 1979 to 2007. Designed by British shipbuilder Brooke Marine and constructed in Australia by NQEA, the Fremantle class were larger, more powerful, and more capable than the preceding , and the two primary patrol boat bases required infrastructure upgrades to support them. Although up to 30 vessels were planned, fifteen were ordered and constructed, with an unexercised option for five more.

Their retirement was announced in 2001 and a decommissioning schedule published in 2004. From May 2005 they were replaced by the patrol boats with the last two Fremantles decommissioning in May 2007. Most of the class were scrapped, with two marked for preservation as museum ships. The Fremantle class has also appeared in two drama television series based on the Royal Australian Navy.

Planning and development

The concept for the Fremantle class began somewhere between 1967 and 1969, as the s entered service, and areas for improvement were observed. In September 1970, the RAN announced the intention to construct ten new patrol boats, which would operate in tandem with the Attack class and replace two general purpose vessels.

Plans of acquisition were announced in April 1975, with eleven shipbuilders submitting tenders, of which two were shortlisted in 1976; Brooke Marine of England and Lürssen Werft of West Germany. The Fremantles were 28% longer and 50% heavier than their predecessors. During sea trials, NUSHIP Fremantle was revealed to be 20 tons over the contracted limit. Main propulsion machinery consisted of two MTU series 538 diesel engines, which supplied to the two propeller shafts. They also had an APU (an Auxiliary Propulsion Unit that was fitted in the interest of fuel saving whilst on patrol: One Dorman 12-cylinder auxiliary propulsion engine.) These were later removed as they proved inefficient when compared to the two main engines although the mortar was removed from all ships sometime in the late 1990s. The main weapon was originally to be two 30-mm guns on a twin-mount, but the reconditioned Bofors were selected to keep costs down; provision was made to install an updated weapon later in the class' service life, but this did not eventuate.

Early on in the construction program, it was realised that the two main patrol boat bases, in Cairns, Queensland and in Darwin, Northern Territory, were not capable of supporting ships of this size on a permanent basis. The final ship of the class, , was commissioned on 15 December 1984. NQEA completed three patrol boats in both 1981 and 1982, and four in both 1983 and 1984. Also by 1984, all of the Attack class had left active service, with many transferring to the RAN Reserve or the Indonesian Navy.

Fate

thumb|right|Gladstone in 2010, awaiting preservation in its [[Gladstone, Queensland|namesake city]]

During 2006 and 2007, most of the Fremantles were broken up for scrap in Darwin, at a cost of between $400,000 and $450,000 each to the Australian government. A total of 11 of the class were dismantled at Darwin, although the MTU engines were salvaged and sold on market, and some high value item were also saved. The exceptions were Wollongong (which was instead scrapped in Port Macquarie), Townsville (gifted to the Townsville Maritime Historical Society for preservation as a museum ship), and (gifted to the Gladstone Maritime Museum for preservation).

Fremantle class in fiction

thumb|left|HMAS Hammersley alongside at

The fictional HMAS Defiance, portrayed by HMA Ships , , , , and featured in the second season of the Australian Broadcasting Corporation television series Patrol Boat.

The fictional HMAS Hammersley is the setting of the first season of Channel Nine's 2007 drama series Sea Patrol. This vessel was portrayed by HMA Ships Wollongong and . A second patrol boat, HMAS Kingston, also appears in the series. From the second season onwards, an Armidale-class boat is used.

Ships

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