In May 1942 the Dutch government offered "K IX" to the Royal Australian Navy for use in anti-submarine warfare training. This offer was accepted and "K IX" arrived in Sydney for repairs on 12 May. On 1 June "K IX" was damaged by a torpedo explosion during the Attack on Sydney Harbour. "K IX" was decommissioned from the Royal Netherlands Navy on 25 July 1942 and following extensive repairs was commissioned into the Royal Australian Navy as HMAS "K9" on 22 June 1943.