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. Toowoomba was laid down at Williamstown, Victoria on 26 July 2002. 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 16 May 2003 by Judy Blight, and commissioned into the RAN on 8 October 2005. Operational history Toowoomba began her first deployment to the Middle East Area of Operations (MEAO) as part of Operation Slipper on 4 January 2007. On 18 June 2008, the frigate became the first RAN warship to fire an MU90 Impact anti-submarine torpedo, after they replaced the American Mark 46 anti-submarine torpedoes originally fitted. In June 2009, Toowoomba sailed from Fleet Base West, Western Australia to embark upon the ship's second MEAO deployment. In September, the frigate was assigned to Combined Task Force 151 (CTF-151); Toowoomba was the first Australian warship to work with CTF-151, a US-led, multinational force tasked with protecting merchant vessels from pirate attacks off the coast of Somalia. Toowoomba was assigned to escort merchant shipping and conduct overt patrols in the International Recommended Transit Corridor (IRTC), a shipping lane extending the Gulf of Aden towards the Somali Basin and the Horn of Africa, in support of United Nations Security Council Resolutions 1846 and 1851. The frigate also operated with the counter-terrorism Combined Task Force 150 (CTF-150) in the Arabian Sea. On 20 September 2009, Toowoomba responded to a call for assistance from the merchant vessel BBC Portugal, and successfully prevented an act of high-seas piracy.