HMAS Assail (P 89) was an Attack-class patrol boat of the Royal Australian Navy (RAN).

[1][2] Propulsion machinery consisted of two 16-cylinder Paxman YJCM diesel engines, which supplied 3,460 shaft horsepower (2,580 kW) to the two propellers.

[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,[citation needed] 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).