and 141 sailors. As designed, the main armament for the frigate is a 5-inch 54 calibre Mark 45 gun, supplemented by an eight-cell Mark 41 vertical launch system (for RIM-7 Sea Sparrow or RIM-162 Evolved Sea Sparrow missiles), two machine guns, and two Mark 32 triple torpedo tube sets (initially firing Mark 46 torpedoes, but later upgraded to use the MU90 Impact torpedo). They were also designed for but not with a close-in weapons system (two Mini Typhoons fitted when required from 2005 onwards), two quad-canister Harpoon anti-ship missile launchers (which were installed across the RAN vessels from 2005 onwards), and a second Mark 41 launcher (which has not been added). The Australian Anzacs use a Sikorsky S-70B-2 Seahawk helicopter; plans to replace them with Kaman SH-2G Super Seasprites were cancelled in 2008 due to ongoing problems. Warramunga was laid down at Williamstown, Victoria on 26 July 1997. The ship was assembled from six hull modules and six superstructure modules; the superstructure modules were fabricated in Whangarei, New Zealand, and hull modules were built at both Williamstown and Newcastle, New South Wales, with final integration at Williamstown. She was launched on 23 May 1998, and commissioned into the RAN on 31 March 2001. On commissioning, the ship was assigned to Fleet Base West. Had the New Zealand government exercised their option for two more frigates, Warramunga was one of the ships that would have been designated for the RNZN. Operational history On 31 July 2006, Warramunga departed Fleet Base West for her first deployment to the Persian Gulf as part of Operation Catalyst, taking over duties from . While on station in the Gulf, Warramunga conducted 150 boardings and security patrols, 320 flying hours were logged by her embarked Seahawk helicopter, and 450 investigative queries of merchant vessels were made. Warramunga returned to Fremantle on 2 February 2007 after 186 days at sea. On 29 May 2009, it was announced that Warramunga would be re-tasked with protecting civilian vessels from piracy in Somali waters. The ship was assigned to Combined Task Force 151, which was tasked with preventing pirate attacks on commercial vessels in the shipping lanes off the Horn of Africa and Somalia. During July and August 2010, Warramunga was one of three RAN ships to participate in the RIMPAC 2010 multinational exercise. During RIMPAC, the frigate participated in the sinking of the decommissioned amphibious assault ship , firing