Page 108 - Australian Defence Magazine May 2022

108 SEAPOWER SURFACE COMBATANTS
MAY 2022 | WWW.AUSTRALIANDEFENCE.COM.AU
though even those could prove formidable adversaries, giv- en the increasing availability of capable anti-shipping mis- siles. But if such scenarios were all we had to worry about then my argument would be mostly about the price of large ships compared to the strategic risk.
POTENTIAL THREATS
But, as should always be the case for capa-
bility planning, strategic risk is at the heart
of the discussion. Because of our geography,
Australia will always be vulnerable to inter-
diction of maritime supply routes. Except
for education, our major export industries
rely on moving bulk materials—which in
practice is only feasible by sea. The Austra-
lian economy would take a major hit if we
couldn’t do that. We also rely on importing
crucial supplies such as refined fuels - and
in times of war that could become a critical vulnerability. And any sizeable ADF deployment into the region is also going to rely on use of the sea. The ability to exert sea con- trol, at least temporarily and over an appreciable area, is a ‘must have’ for Australia. The question is how we can best do it—and I’m unconvinced that relying predominantly on $5+ billion frigates and destroyers are the best solution.
ABOVE: HMAS Brisbane launches an Evolved Sea Sparrow Missile during Exercise Pacific Vanguard
If we’re going to include persistence in the value propo- sition for warships, we better be confident that they are capable of hanging around in contested waters. That’s why the size of the magazine matters a lot. In the air domain, analysts have criticised the small number of missiles the
F-35 can carry internally. But breaking off from air-to-air combat is often relatively easy, while ships will be potentially in harm’s way for hours or days at a time. They are large and slow, hard to render low-observ- able, defensive systems based around large missiles can’t be reloaded at sea, and they are confined to manoeuvring in two dimensions. Conversely, the threats they face are small, fast, potentially numerous and are able to manoeuvre in three dimensions. Emerging threats include hypersonic anti-ship ballistic missiles and cruise weapons.
Ships can be subjected to repeated attacks over the course of a mission in hot wars, and the mathematics of cumulative probabilities applies. To be quantitative, if a ship has a defensive system that is (generously) 90 per cent effective against an incoming threat, then it has an 81 per cent chance of avoiding a hit from a salvo of two weapons. But it has only an even chance of defeating all of the weap- ons if the adversary gets in six shots - and the probabilities are likely to go down even further if the threats have to be dealt with concurrently) With those sorts of numbers a naval task group is going to take hits if there is serious op- position—and that’s what has been seen historically.
“BECAUSE OF
OUR GEOGRAPHY, AUSTRALIA WILL ALWAYS BE VULNERABLE TO INTERDICTION OF MARITIME SUPPLY ROUTES”
DEFENCE