See main article: Attack-class patrol boat. The Attack class was ordered in 1964 to operate in Australian waters as patrol boats (based on lessons learned through using the s on patrols of Borneo during the Indonesia-Malaysia Confrontation, and to replace a variety of old patrol, search-and-rescue, and general-purpose craft. Initially, nine were ordered for the RAN, with another five for Papua New Guinea's Australian-run coastal security force, although another six ships were ordered to bring the class to twenty vessels. The patrol boats had a displacement of 100 tons at standard load and 146 tons at full load, were in length overall, had a beam of 20feet, and draughts of at standard load, and 7.3feet at full load.[1] [2] Propulsion machinery consisted of two 16-cylinder Paxman YJCM diesel engines, which supplied to the two propellers.[1] [2] The vessels could achieve a top speed of, and had a range of at .[1] [2] The ship's company consisted of three officers and sixteen sailors.[2] Main armament was a bow-mounted Bofors 40 mm gun, supplemented by two .50-calibre M2 Browning machine guns and various small arms.[1] [2] The ships were designed with as many commercial components as possible: the Attacks were to operate in remote regions of Australia and New Guinea, and a town's hardware store would be more accessible than home base in a mechanical emergency.[3]
Assail was built by Evans Deakin and Company at Brisbane, Queensland,[4] launched on 18 November 1967, and commissioned on 12 July 1968.[4]
Assail paid off on 18 October 1985, and was transferred to the Indonesian Navy and renamed KRI Sigurot (864).[5] [6] The patrol boat was listed in Jane's Fighting Ships as still operational in 2011.[6]