HMAS Tamworth (J181)

[1] In 1938, the Australian Commonwealth Naval Board (ACNB) identified the need for a general purpose 'local defence vessel' capable of both anti-submarine and mine-warfare duties, while easy to construct and operate.

[2][3] The vessel was initially envisaged as having a displacement of approximately 500 tons, a speed of at least 10 knots (19 km/h; 12 mph), and a range of 2,000 nautical miles (3,700 km; 2,300 mi)[4] The opportunity to build a prototype in the place of a cancelled Bar-class boom defence vessel saw the proposed design increased to a 680-ton vessel, with a 15.5 knots (28.7 km/h; 17.8 mph) top speed, and a range of 2,850 nautical miles (5,280 km; 3,280 mi), armed with a 4 inch Mk XIX gun, equipped with asdic, and able to fitted with either depth charges or minesweeping equipment depending on the planned operations: although closer in size to a sloop than a local defence vessel, the resulting increased capabilities were accepted due to advantages over British-designed mine warfare and anti-submarine vessels.

[6] The need for locally built 'all-rounder' vessels at the start of World War II saw the "Australian Minesweepers" (designated as such to hide their anti-submarine capability, but popularly referred to as "corvettes") approved in September 1939, with 60 constructed during the course of the war: 36 ordered by the RAN, 20 (including Tamworth) ordered by the British Admiralty but manned and commissioned as RAN vessels, and 4 for the Royal Indian Navy.

[10][11] After a brief period of service as a training vessel in Australian waters was transferred to the Royal Netherlands Navy on 30 April 1946.

[1] Following this, the ship was transferred to the Indonesian Navy, renamed RI Pati Unus, and served until disposal in 1969.