[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).
[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 (including Katoomba) ordered by the RAN, 20 ordered by the British Admiralty but crewed and commissioned as RAN vessels, and 4 for the Royal Indian Navy.
[1] At the end of June, Katoomba was reassigned as a convoy escort and anti-submarine patrol ship in the waters of northern Queensland and New Guinea.
[1] The corvette returned to Australian waters, spent three months in Fremantle, then was assigned to Darwin, where she operated until the end of World War II.