HMAS Waterhen (D22/I22) was a W-class destroyer that served in the Royal Navy (as HMS Waterhen (G28/D22)) and the Royal Australian Navy (RAN). Built during World War I, the destroyer was completed in mid 1918, and commissioned into the Royal Navy. In 1933, Waterhen and four other British ships were transferred to the RAN. The ship's early RAN career was uneventful, with periods spent decommissioned in reserve, but she was reactivated in September 1939, and deployed to the Mediterranean as part of the Australian destroyer force: the Scrap Iron Flotilla. During her time in the Mediterranean, Waterhen was involved in escort and patrol duties, performed shore bombardments, and participated in Allied evacuations from Greece and Crete. On 29 June 1941, while operating with the Tobruk Ferry Service, Waterhen was heavily damaged by Axis aircraft. Attempts to tow the ship to port were unsuccessful, and she sank on 30 June 1941, the first RAN ship lost to combat in World War II. Design and construction Waterhen was a W-class destroyer constructed for the Royal Navy during World War I. The ship had a displacement of 1,100 tons at standard load, was in length overall and long between perpendiculars, had a beam of , and a maximum draught of . Propulsion machinery consisted of three Yarrow boilers feeding two Brown-Curtis turbines, which provided to the two propeller shafts. Maximum designed speed was . Waterhen had a range of at . The ship's company consisted of 6 officers and 113 sailors. At launch, Waterhens main armament consisted of four single QF Mark V guns. This was supplemented by a quad-barelled QF 2-pounder naval gun, and five .303 inch machine guns of various types. The destroyer was also fitted with two 3-tube torpedo sets, two depth charge chutes, and four depth charge throwers. Later modifications to her armament included the installation of a second 2-pounder gun, and the replacement of the torpedo tube sets with two 4-tube sets. Waterhen was laid down by Palmers Shipbuilding and Iron Company at their shipyard in Hebburn-on-Tyne on 3 July 1917. She was launched on 26 March 1918. The destroyer was completed on 17 July 1918, and was commissioned into the Royal Navy. Operational history Transfer to RAN In 1933, the British Admiralty decided to replace five destroyers on loan to the RAN with five more capable (but slightly older) destroyers. Waterhen was one of the five ships