HMAS Sydney, one of Australia’s three Hobart-class air warfare destroyers this month became the first Australian warship to test fire Raytheon’s RIM-174A SM-6 missile, during Exercise Pacific Dragon off Hawaii. This followed hot on the heels of HMAS Sydney’s first launch of Kongsberg’s Naval Strike Missile (NSM) against a target ship during the biennial RIMPAC exercise. It is not clear what was the target for the SM-6 test.
Both of these missile types are earmarked to enter service with the Royal Australian Navy (RAN). The SM-6 will be added to the missile armament aboard the Hobart-class destroyers and eventually the Hunter-class frigates.
Australia’s government has touted these tests as a demonstration of greater depth and range in the Australian Defence Force’s missile armoury, as it seeks to realise the more focused and lethal force mandated in the 2023 Defence Strategic Review and this year’s National Defence Strategy.
Both missiles are potent additions to the RAN’s firepower. However, what sets the SM-6 apart in Australia’s modestly sized missile arsenal is the impressive versatility in capability that it brings.
Like the SM-2 and ESSM, which are also carried by Australian warships and are fired from the same vertical launch cells, the SM-6 was primarily designed as an air-defence weapon. Defending against incoming aircraft and cruise missiles remains one of its functions. It is also capable of ballistic-missile defence in conjunction with the Aegis Baseline 9 combat system, with which the Hobarts will be upgraded.
Although official Australian statements have emphasised the SM-6’s air defence role, the missile can also target ships. Its effective range in that mode is not known but is likely to be significantly longer than the advertised 185km reach of the NSM, which is already an improvement upon the Harpoon missile that is being phased out as the Anzac-class frigates are progressively decommissioned. SM-6’s anti-ship function is attractive for the RAN, as the missile’s range and speed promise to restore a tactical edge in case of surface encounters with well-armed adversaries. China’s large and expanding navy is the likely benchmark.
The downsides of employing the SM-6 in this role are the high unit-cost of the missile, US$4.3 million, and its relatively small warhead. The NSM, which is half the price but is a slower-moving cruise missile, will serve as the RAN’s mainstay anti-ship missile in future. Still, the versality of the SM-6 makes it a handy force multiplier for the RAN, since its ships carry few missiles and could be reloaded only at long intervals when deployed forward. A missile that can perform several different tasks is very useful when sailing into harm’s way, as an adversary must take the all-round capability into account.
The versatility of the SM-6 now extends into the air domain, with the US Navy showing it at RIMPAC mounted on an F/A-18E/F Super Hornet as an air-to-air missile. With an estimated range of 400 km, the AIM-174B, the air-launched version of SM-6, promises to fill a significant gap in US air defence capability by reaching aerial threats that couldn’t formerly be intercepted. While other US Navy and Air Force contenders to fill this requirement are under development, the AIM-174B could be an attractive and readily available option for the Australian air force to acquire from its ally. Australia also operates the Super Hornet, the avionics of which should be readily adaptable to controlling the AIM-174B.
Australia may not be making progress in retooling the ADF’s lethality as fast as many observers would like. But the successful testing of the NSM and SM-6 certainly point in the right direction for the navy. Their combined and complementary anti-ship capabilities are likely to be highly prized. The SM-6’s multi-functionality does not come cheap, but it appears to be a prudent investment in the current and future combat capability of Australia’s surface naval force.