Nigel Pittaway | Melbourne
However Australia also has a maritime strike requirement, for which there is currently no suitable US weapon and if a suitable weapon is found, it must be integrated into the F-35A before Final Operating Capability is declared around 2022-23.
One of the major advantages of the F-35 is low observability but, to remain stealthy, weapons have to be carried internally and therefore the dimensions of the weapons bay will arguably restrict the future choice of some weapons and dictate US weapons size for decades to come.
As planned, Australia’s F-35As will arrive with Block 3F software which will be integrated with the Raytheon AIM-120C Advanced Medium Range Air to Air Missile (AMRAAM) and a number of air to ground munitions, such as the GBU-31 Joint Direct Attack Munition (JDAM).
In a ‘first day of the war’ (i.e. stealthy) configuration, RAAF F-35As will be able to carry four AMRAAMs (two in each weapons bay) for air to air missions, or two AMRAAMs and two JDAM 2,000lb bombs for the air to ground scenario.
Lockheed Martin is currently redesigning the weapons bays and doors to allow carriage of up to three AMRAAMs in each bay, increasing air to air combat persistence by 50 per cent. If stealth is not the primary concern (in a scenario the US calls ‘day two of the war’), weapons can be carried externally on seven pylons.
In this later case, eight AMRAAMs and two within visual range Raytheon AIM-9X Sidewinder missiles can be carried in the air to air role. The AIM-9X cannot yet be carried internally because it is a ‘heat-seeking’ weapon and therefore needs to ‘see’ a heat source before launch. Raytheon is developing the AIM-9X Block II, which will have lock on after launch capability and a one way forward datalink added.
Air to ground weapons to be certified at delivery includes GBU-12 Paveway II 500lb Laser-Guided Bombs, GBU-31 JDAM, GBU-39 250lb Small Diameter Bomb and Raytheon AGM-154C-1 Joint Stand Off Weapon.
“At IOC that gives us the basic ‘go to war capability’, for FOC clearly we would want the full functionality of those weapons and capability inherent in them, with the intent of having the best maritime strike weapon on the aircraft as well,” JSF Program Manager, Air Vice Marshal Chris Deeble explained to ADM.
Maritime strike weapon
Very few of the currently available (or planned) advanced maritime strike weapons will fit in the F-35A weapons bay and this is one area where Australia may deviate from the US baseline.
The US is developing a Long Range Anti Ship Missile (LRASM), based on the Lockheed Martin JASSM-ER, but this is too large for internal carriage in the F-35.
Australia is closely watching the development of Norway’s Joint Strike Missile, an air launched version of the Kongsberg Naval Strike Missile, which will be integrated into the F-35A in the 2022-24 timeframe for the Royal Norwegian Air Force.
“The JSF Program Office is working closely with Capability Development Group at the moment on opportunities to work with Norway to better understand the integration issues and influence the further development of the Joint Strike Missile,” AVM Deeble said.
Internal gun
One of the few areas where Australia has actually deviated from the US baseline is in the ammunition for the F-35As internal gun.
A single General Dynamics GAU-22/A 25mm four-barrel gun is mounted above the left hand wing root of the F-35A, with 182 rounds of ammunition.
For the gun, Australia has selected the Nammo APEX (Armour Piercing Explosive) round in collaboration with Norway.
“The APEX round is different to what’s being currently planned to be utilised by the US. We believe it is better suited to our operational environments and needs in that regard,” AVM Deeble detailed. “But generally speaking, our aim is to stay with the US weapon roadmap to the maximum extent possible, unless we can identify weapons that are unique to our requirements.”
External tanks
Although not weapons of course, the issue of external fuel tanks is an interesting subject and it is known that Israel is carefully studying the establishment of the capability.
AVM Deeble said that while Australia had previously looked at the possibility of putting external tanks on the JSF in the very early days it was subsequently discounted because they didn’t offer any significantly increased range.
However the Israelis have revisited the issue and are considering tanks with a much reduced drag index and Australia may also look at the prospect of external tank carriage once again.
“Once you carry something as big as that, irrespective of trying to reduce its radar cross-section, it’s going to increase your overall signature,” AVM Deeble considered.
“So understanding operationally how you would employ them and what it actually meant for real-world operations, as opposed to ferrying from Point A to Point B, is what we are doing now and we’ll always consider options, but they need to be proven and represent value for money at the end of the day.”
Roadmap for the future
The desire for commonality will probably mean Australia will be closely linked to the US weapons roadmap, although AVM Deeble notes the Force Structure Review and White Paper may provide further guidance.
“Future weapons consideration is really in that advanced maritime strike area. That’s really the area which is open for discussion,” he said. “In the longer term, if you are looking at 5th generation-type weapons and towards the 6th generation, there are many things that can be considered, hypersonic weapons and others, that we would be interested in looking at from an R&D perspective in the short to medium term.”
Weapons datalink developments may also be part of the F-35 future as there is potential for Link 16 to be over-subscribed and other datalinks or wave forms might be needed to support those weapons.
“When you consider the JSF is going to be around for 30 years, I don’t envisage the current weapons suite surviving that long without having to go through an evolution,” AVM Deeble concluded.
“US policy now requires any weapon coming in as a program of record, to have more utility than a single-seeker and that will clearly lead to evolution of a range of weapons to provide maximum utility in the battlespace.”