An increasingly common sight in the Pacific has been the three-ship Hobart class of Aegis-equipped air warfare destroyers, on which the future of Australian air defense at sea rests.
The destroyers began life 20 years ago as a proposal in a government Defense White Paper. Design competitions and selection took place during the 2000s, followed by construction in Australia during the 2010s by the Air Warfare Destroyer Alliance. The design is based on the Spanish Álvaro de Bazán–class (Project F-100) guided-missile frigates, but it features a number of enhancements. Significant delays and cost overruns overshadowed the class’s early development, but today the destroyers have evolved into some of the Pacific region’s premier air-defense warships.
Laid down in 2012 and launched on 23 May 2015, HMAS Hobart was commissioned on 23 September 2017. Sister ships HMAS Brisbane and Sydney joined the fleet on 27 October 2018 and 18 May 2020, respectively. The three warships employ the Lockheed Martin AN/SPY-1D(V) multifunction phased-array radar in conjunction with RIM-162 Evolved Seasparrow (ESSM) and SM-2 surface-to-air missiles fitted in a 48-cell Mk 41 vertical launching system. The SM-2s can engage enemy aircraft and missiles at ranges in excess of 80 nautical miles (nm), while the medium-range ESSMs can reach out 27 nm. In the future, the 200-plus nm range SM-6 missile is expected to be carried.
Eight RGM-84 Harpoon antiship missiles are fitted amidships, while a 5-inch Mk 45 gun is mounted forward, a Phalanx close-in weapon system is fitted atop the helicopter hangar, and two M242 25-mm Bushmaster guns are carried in remotely operated Typhoon mounts on either side of the bridge.
For antisubmarine warfare, the destroyers operate an integrated sonar system incorporating hull-mounted and towed-array sonars and are armed with two sets of Mk 32 Mod 9 torpedo tubes. These are dual-tube variants of the triple-tube Mk 32 torpedo tubes found on board many U.S. warships, although the Australian versions have been modified to carry EuroTorp MU90 torpedoes. A single MH-60R Seahawk maritime helicopter is embarked to support a wide variety of naval missions.
The Hobarts measure 481 feet long, with a 61-foot beam and 24-foot draft. Displacing 7,000 tons fully loaded, the destroyers are around 25 percent smaller than the U.S. Arleigh Burke class, but with only 180 personnel assigned, her crew complement is roughly half that of a U.S. destroyer.
A combined diesel and gas (CODAG) propulsion system, consisting of two 23,500-horsepower gas turbines and two 7,580-horsepower diesel engines, powers the Australian destroyers. This permits a top speed in excess of 28 knots and a cruising range of 4,500 nautical miles at 18 knots.
In September 2018, the Hobart joined U.S. naval forces for a cooperative deployment in the eastern Pacific, and in fall 2019, she concluded her first operational deployment, forming part of a multi-ship and submarine task force representing Australia across a wide swath of the Pacific. That same autumn, the Brisbane visited the United States, operating off the coast of Hawaii and taking part in Fleet Week in San Francisco, California.