HMAS Acute (P 81) was an Attack class patrol boat

Attack class patrol boat

The Attack class patrol boats were small coastal defence vessels built for the Royal Australian Navy and operated between 1967 and 1985...

 operated by the Royal Australian Navy

Royal Australian Navy

The Royal Australian Navy is the naval branch of the Australian Defence Force. Following the Federation of Australia in 1901, the ships and resources of the separate colonial navies were integrated into a national force: the Commonwealth Naval Forces...

 (RAN).

Design and construction

The Attack class was ordered in 1964 to operate in Australian waters as patrol boat

Patrol boat

A patrol boat is a relatively small naval vessel generally designed for coastal defense duties.There have been many designs for patrol boats. They may be operated by a nation's navy, coast guard, or police force, and may be intended for marine and/or estuarine or river environments...

s (based on lessons learned through using the Ton class minesweeper

Ton class minesweeper

The Ton class were coastal minesweepers built in the 1950s for the Royal Navy, but also used by other navies such as the South African Navy and the Royal Australian Navy...

s on patrols of Borneo during the Indonesia-Malaysia Confrontation

Indonesia-Malaysia confrontation

Indonesia–Malaysia confrontation during 1962–1966 was Indonesia’s political and armed opposition to the creation of Malaysia. It is also known by its Indonesian/Malay name Konfrontasi...

, 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

Papua New Guinea

Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands...

'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 107.6 feet (32.8 m) in length overall, had a beam of 20 feet (6.1 m), and draughts of 6.4 feet (2 m) at standard load, and 7.3 feet (2.2 m) at full load. Propulsion machinery consisted of two 16-cylinder Paxman YJCM diesel engines, which supplied 3460 shp to the two propellers. The vessels could achieve a top speed of 24 knots (13.1 m/s), and had a range of 1200 nautical miles (2,222.4 km) at 13 knots (7.1 m/s). The ship's company consisted of three officers and sixteen sailors. Main armament was a bow-mounted Bofors 40 mm gun, supplemented by two .50 calibre M2 Browning machine guns and various small arms. 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.

Acute was laid down by Evans Deakin and Company

Evans Deakin and Company

Evans Deakin and Company was an Australian engineering company and shipbuilder. Originally based in Brisbane, the company was started in 1910 by Daniel Evans and Arthur Deakin. The company started out as a supplier of engineering equipment. The first workshop was acquired in 1913.The company later...

 at Brisbane, launched on 26 August 1967, and commissioned on 26 April 1968.

Operational history

Acute was predominantly used for training of Royal Australian Navy Reserve personnel at Fremantle, Western Australia

Fremantle, Western Australia

Fremantle is a city in Western Australia, located at the mouth of the Swan River. Fremantle Harbour serves as the port of Perth, the state capital. Fremantle was the first area settled by the Swan River colonists in 1829...

. Whilst on a training cruise in May 1983, Acute apprehended two Taiwanese fishing boats engaged in illegal fishing. This was the first such operation involving RANR personnel.

Acute paid off on 6 May 1983. She was transferred to the Indonesian Navy

Indonesian Navy

The role of the Indonesian Navy is to patrol of Indonesia's immense coastline, to ensure safeguard the territorial waters and Exclusive Economic Zone , to protect Indonesia's maritime strategic interests, to protect the islands surrounded Indonesia and to defend against seaborne threats. The TNI...

and renamed Silea.