Armidale - class patrol boat The " Armidale " class is a class of patrol boat s built for the Royal Australian Navy ( RAN ) . Planning for a class of vessels to replace the fifteen " Fremantle " class patrol boats began in 1993 as a joint project with the Royal Malaysian Navy , but was cancelled when Malaysia pulled out of the process . The project was reopened in 1999 under the designation SEA 1444 , with the RAN as the sole participant . Of the seven proposals tendered , the Austal Ships / Defence Maritime Services proposal for twelve vessels based on an enlarged was selected . The first vessel , , commissioned into the RAN in June 2005 . Two more patrol boats were ordered in 2005 to provide a dedicated patrol force for the North West Shelf Venture , bringing the class to fourteen . The " Armidale " s are longer and heavier than their " Fremantle " class predecessors , with improved seakeeping ability and increased range , allowing them to reach Australia ' s offshore territories . The ships are multi - crewed , with three ship ' s companies available for every two vessels ; this allows the patrol boats to spend more time at sea without cutting into sailors rest or training time . However , during their early service life , there were problems with the fuel systems across the class , and a 20 - bunk auxiliary accommodation compartment has been banned from use after toxic fumes were found in the compartment on at least two occasions . All fourteen vessels were constructed by Austal Ships at Henderson , Western Australia , with the last entering service in February 2008 . The " Armidale " class ships are operated by the Australian Patrol Boat Group , and based in Cairns and Darwin . They are primarily tasked with border protection , fisheries patrols , and the interception of unauthorised arrival s by sea , although two vessels are permanently assigned to protecting the oil and gas production facilities of the North West Shelf Venture . A fictional " Armidale " class boat , HMAS " Hammersley " , appears in the Australian military drama series " Sea Patrol " from the second season onwards . Development and tendering . Planning for the " Armidale " class began in 1993 , as a plan to replace the " Fremantle " class , which was due for retirement in 1998 . This evolved into a joint program with Malaysia to construct an offshore patrol craft . When Malaysia pulled out , the plan was scrapped , and the " Fremantle " s underwent a life - extending refit . The cost of maintaining the aging vessels prompted the Department of Defence to create the Replacement Patrol Boat program , which received the procurement project designation SEA 1444 . SEA 1444 marked several departures from the Department ' s standard acquisition requirements . Instead of specifying a number of vessels , the coverage of 3 , 000 ship - days per year ( with 1 , 800 to be spent on border protection operations , and a surge capability of 3 , 600 days ) was given , with the producer to determine how many ships were needed to meet this . The ships had to meet specific performance parameters , such as the ability to conduct boarding operations in conditions up to Sea State 4 , and to maintain surveillance capability up to Sea State 5 . The producer was also required in the contract to provide support and maintenance for the ships , for fifteen years after construction completed . Nine companies expressed interest in the project ; of these , seven had the required capability to build the ships . These seven were narrowed down to three based on each tender ' s merit , competitiveness with the other tenders , and successful meeting of Australian industry involvement targets for both construction and long - term support . Austal Ships and Defence Maritime Services ( DMS ) partnered to offer twelve ships based on an expanded version of the latter ' s " Bay " class patrol boat , in use with the Australian Customs Service . The companies submitted two proposals for a vessel , one with a steel hull , and one with an aluminium hull ; the latter offering a 21 % reduction in fuel consumption . Australian Defence Industries ( ADI ) tendered a design based on the Royal Danish Navy ' s " Flyvefisken " class patrol vessel . The vessel was to be built with a glass - reinforced plastic hull , similar to ADI ' s " Huon " class minehunters . The Tenix proposal was a variant of the search and rescue vessel constructed for the Philippine Coast Guard . The tender was awarded to the Austal / DMS partnership in December 2003 . The contract was valued at A $ 553 million , with each ship costing between A $ 24 million and A $ 28 million to construct . During the 2004 federal election , the Coalition promised to acquire two more patrol boats to provide a dedicated patrol force for the oil and gas producing facilities located off the north - west coast of Australia . These were ordered in 2005 . Design and construction . All fourteen ships were constructed by Austal at their shipyard in Henderson , Western Australia . Lead ship was commissioned into the RAN in June 2005 . Two other patrol boats were delivered to the RAN in 2005 , six in 2006 , and five in 2007 , with the final ship in the class , , delivered in October 2007 and commissioned in February 2008 . At one stage , six vessels were being constructed simultaneously . Each patrol boat has a length of , a beam of , a maximum draught of , and a displacement of 270 tons . The hull is of the semi - displacement vee type , and is fabricated from aluminum alloy . The ship is designed to a combination of Det Norske Veritas standards for high - speed light craft and RAN requirements : a lot of effort went into avoiding attempts to overengineer the " Armidale " s or turn them into ' miniature warships ' . The " Armidale " s can travel at a maximum speed of , and are driven by two propeller shafts , each connected to an MTU 16V M70 diesel . The ships have a range of at , allowing them to patrol the waters around the distant territories of Australia , including the Cocos ( Keeling ) Islands and Christmas Island . The " Armidale " class has demonstrated an improved seakeeping ability over the preceding " Fremantle " class : the " Armidale " s are longer , 85 tons heavier , and have hydraulic stabiliser fins and trim tab s incorporated into the design , allowing them to survive conditions up to Sea State 9 . The vessels are designed for standard patrols of 21 days , with a maximum endurance of 42 days . Weapons and systems . The main armament of the " Armidale " class is a Rafael Typhoon stabilised gun mount fitted with an M242 Bushmaster cannon . This cannon has a rate of fire of 200 rounds per minute , and is controlled remotely from the bridge . Two machine guns are also carried . Boarding operations are performed by two , waterjet propelled rigid - hulled inflatable boat s ( RHIB ) , which carry ten people ( a fully equipped , eight - strong boarding party , and two boat crew ) . The RHIBs are larger and more powerful than the single RHIB aboard a " Fremantle " , are capable of operating independently of their mothership , and carry their own communications , navigation , and safety equipment . Each RHIB has a dedicated cradle and davit , the boats can be launched and recovered easily , and a centralised ' dressing room ' incorporated into the ship ' s design has streamlined the deployment and return of personnel . The patrol boats are fitted with S band and X band surface search radars , a Toplite electro - optical detection system , and a Warrlock direction finding system . A Prism III radar warning system was fitted to the last two boats during construction , and refitted to the rest . Complement . Each patrol boat has a standard ship ' s company of 21 personnel , with a maximum of 29 ( not including use of the austere compartment ) . Unlike the " Fremantle " class patrol boats , the " Armidale " s do not have a permanently assigned ship ' s company . Instead , there are 21 crews established for the 14 " Armidale " class patrol boats , which are divided up into four divisions : " Attack " , " Assail " , " Ardent " , and " Aware " . The first three of the Divisions are assigned six crews for four ships , while " Aware " has three crews for two ships . The ships are continually manned , with two out of three crews actively deployed while the third undergoes leave or training , or prepares to transfer into a ship : a handover can be accomplished in less than six hours . The intention of multi - crewing is to allow the ships to spend more time at sea , without compromising sailors ' rest time or training requirements . Junior sailors are housed in four - berth cabins , as opposed to the central sixteen - berth mess deck of the " Fremantle " s , while senior sailors and commissioned officers either have individual or share two - berth cabins . Personnel have access to e - mail and satellite television , and the galley is better equipped than that on a " Fremantle " class vessel and better suited to use in heavy seas . The comfort of personnel is also significantly improved over the " Fremantle " s , with air conditioning throughout the entire ship ( excluding engine and machinery compartments ) . Introduction into service . The introduction of the class into service has not been without problems . Since June 2005 , all active " Armidale " s have undergone operating restrictions on two occasions , both due to water contamination of the main fuel systems . The first occurrence , in September 2006 , led to the suspension of operations by the patrol boats for a month , and the engineering controls were redesigned . The problem occurred again in January 2007 , and led to an ' operational pause ' while Austal redesigned the fuel system , engineering procedures were altered , and fuel quality criteria were tightened . The five ships yet to be completed were fitted with the modified fuel system during construction , while the active ships were refitted over the course of 2007 . As of December 2007 , no further fuel problems have occurred . A 20 - berth auxiliary accommodation compartment was included in the design , for the transportation of soldiers , illegal fishermen , or unauthorised arrivals ; in the latter two cases , the compartment could be secured from the outside . However , a malfunction in the sewerage treatment facilities aboard in August 2006 pumped hydrogen sulfide and carbon monoxide into the compartment , non - fatally poisoning four sailors working inside . Use of the compartment as accommodation was banned across the class . In 2009 , a sailor working in the compartment on a different vessel was also gassed with hydrogen sulfide , and carbon monoxide was regularly detected in the enclosed space . Operations . The " Armidale " class ships are operated by the Australian Patrol Boat Group and are primarily tasked with border protection and fisheries patrols . As of 2009 , up to seven " Armidale " class boats are assigned to patrols of Australian waters at any given time as part of Operation Resolute , with an increase to nine of the fourteen vessels when required . " Ardent " Division and four ships are based at HMAS " Cairns " in Cairns , while the other three divisions and ten ships are located at HMAS " Coonawarra " in Darwin . Up to two ships ( typically HMA Ships and , plus " Aware " Division ) can be forward - based at Dampier , Western Australia , facilitating patrols of the oil and gas producing facilities located off the north - west coast of Australia . Appearances in fiction . From the second season onwards of " Sea Patrol " , an Australian military drama series , the fictional " Armidale " class patrol boat HMAS " Hammersley " ( pennant number 82 ) is used as the main setting . In 2008 , two ships were conflated to represent " Hammersley " : 42 of the 86 days of filming were spent aboard , with later pick - up filming aboard . Replacement . " " , the 2009 Department of Defence white paper , proposed replacing the " Armidale " s , along with the RAN ' s mine warfare and hydrographic vessels , with a single class of multi - role offshore combatant vessels ( OCVs ) . The new vessels , which could displace up to 2 , 000 tonnes and be equipped for helicopter or unmanned aerial vehicle operations , will use a modular mission payload system to change between roles as required . Although the 2013 White Paper committed to the OCV as a long - term plan , it announced that an interim patrol boat class based on an existing design would be acquired as a short - term replacement .