Friday, September 12, 2008

The integrated air defence system Australia had to have.

Australia enjoys a unique geographical position with perhaps the most strategic depth of any nation. However this tyranny of distance comes at a price. With an arc measuring over 6500 km’s of air and ocean that make up the sea-air gap to our north, calling the task of defending our northern approaches for a navy of twelve major surface combatants and six submarines challenging is perhaps somewhat of an understatement. Therefore the long range, firepower and speed of response that air power provides means the RAAF will always play the primary role in the defence of the sea-air gap. The RAAF’s ability to monitor, operate in and dominate the battle space to our north is and has been a cornerstone of the nations defence in the post world war era. Consequently in order to maintain the capability edge the RAAF has enjoyed over our neighbors in the last 6 decades a world class, integrated air defence system has been implemented by the ADF and should be fully operational by 2013.

An improved kill chain:

In order to implement the improvement in capability needed every link in the kill chain is either undergoing significant upgrade or new elements are being added to achieve a truly flexible and lethal air combat system.

Providing theatre wide ISR capability is the Jindalee Operational Radar Network (JORN) which has a range in excess of 3000km’s. JORN provides early warning capability throughout the sea-air gap and is capable of monitoring most aircraft (non-VLO) and practically all naval traffic throughout the northern approaches. The system works by refracting HF radio waves off the ionosphere to achieve ranges well beyond conventional radar limitations. The transmitter and receiver arrays are both located in central Australia over 1000km’s inland at Longreach Queensland and Laverton Western Australia. This distance from any threat does limit the systems vulnerability, with only a small number of global powers possessing the capability to effectively reach the systems vital components and none in our region. It appears the system does have some current limitations however; the resolution achieved by HF may not be high enough for weapons cueing, particularly when dealing with airborne threats. Therefore JORN can not effectively act as a targeting platform and is essentially a wide area surveillance asset.

JORN's sensor footprint







In order to provide target quality radar track data on air and sea targets the RAAF has ordered 6 E-737 Wedgetail Airborne Early Warning & Control (AEW&C) aircraft scheduled for initial operating capability (IOC) in 2010. Each of these world leading new platforms is equipped with Northrop Grumman’s revolutionary Multi-role Electronically Scanned Array (MESA) radar, which is in effect a large and extremely sophisticated AESA. Exact radar capabilities are classified but the MESA is reported to have an IFF (Identify Friend or Foe) range in excess of 500 kilometres and can track over 3000 targets. The L band MESA will be able to very precisely track small, high speed, low altitude targets such as Anti Ship Missiles in addition to allowing individual platforms to take ‘EM cold’ AIM-120 missile shots. Wedgetail will provide the ADF with a stand off targeting and surveillance capability that is highly mobile, extremely capable and precise. It is likely to be the nucleus of all future RAAF packages after its introduction.


E737 Wedgetail







The RAAF’s main air superiority asset, the F/A-18C/D HUG Hornet is likely to continue to see service until 2017. The Hornet fleet has undergone significant upgrades throughout its service with the RAAF and is now far more capable than when originally delivered. The inclusion of the AN/APG-73 radar, a fully glassed cockpit, Link 16, AN/ALR-67(V)3 Radar Warning Receiver (RWR) and a modernized weapons suite including the AIM-132 ASRAAM provides the RAAF with a very capable platform even considering the current and projected threat environment.

F/A-18C Hornet


With the announcement of the retirement of the F-111C~G fleet in 2010 and its replacement with the F/A-18F Block II the RAAF will receive its first new combat platform in over 20 years. The F/A-18F BII is a highly sophisticated multi role fighter that is based on a revised legacy Hornet airframe and is about 30% larger. Although visually the Super Hornet may seem similar to its predecessor the two only share only 10% commonality. The F/A-18F BII is equipped with a “5th generation” avionics suite lifted from failed X-32 JSF contender built around the AN/APG-79 AESA radar. This system is described by many as the most capable fighter sized radar operational anywhere, with extremely small side lobes, significantly greater detection and track radii than legacy radar’s, Low Probability of Intercept (LPI) search and track, improved resistance to Electronic Countermeasures (ECM), a latent electronic attack capability (EA) and near instantaneous scan rates. This in combination with the other advanced features of the avionics suite such as the world leading Human User Interface (HUI), fibre-optic data bus and digital AN/ALR-67 (V)3 RWR makes the F/A-18F BII an extremely capable strike asset and Beyond Visual Range (BVR) fighter.

F/A-18F Super Hornet







The addition of the F-35A to the RAAF’s order of battle in 2015 (under the current plans) will add LO to the significant capabilities the Super Hornet provides, in addition to an even more advanced HUI, Electro Optical (EO) and Electronic Warfare (EW) suite’s. The 5th generation F-35A is a quantum leap in capability as the first LO platform operated by the RAAF, and is at least half a generation ahead of any possible threat platform out to 2025.

The RAAF has operated nearly all of the AIM-120 AMRAAM derivatives, AIM-120B first integrated on the F/A-18C/D fleet in 2002. This BVR missile has been the cornerstone of western aligned air forces for the last decade and was the first air to air missile equipped with an active radar seeker and data link to see widespread use. The latest derivative of the AMRAAM series is the AIM-120D, which will reach IOC with the USAF and USN later this year. The AIM-120D is a significantly improved AMRAAM derivative, with a maximum engagement envelope of over 180 kilometres; which is some 50 kilometres more than the longest ranging missile in the SU-30’s inventory, the R-27 ER/EA Alamo Long Burn. The AIM-120D also provides a significantly advanced seeker with improved Electronic Counter-Counter Measures (ECCM), larger acquisition basket and the ability to engage a target more intelligently. A major capability the AIM-120D provides is an improved two way data link which allows the missile to actively communicate with the launch platform relaying target acquisition data and other information. An additional capability this data link provides is the AIM-120D can be updated directly from a 3rd party, such as another platform or AEW&C asset. Currently equipped with the AIM-120C5 variant, the RAAF is almost certain to acquire the AIM-120D as soon as it is made available for export.

AIM-120D





With the retirement of the F-111 fleet and its replacement with the Super Hornet every platform in the RAAF’s order of battle will be Link 16 compatible. This high speed, high capacity, “unjamable” data link can transmit at up to 115.2 kbps allowing platforms to exchange tactical information in near real time. At the package or squadron level, Link 16 provides every platform an AEW&C generated radar picture that in addition to achieving much higher detection & track radii, will provide LPI and better ECCM (significantly so when compared to the AN/APG-73). This technique will allow said platform to engage targets without using their own radars for target acquisition and illumination which is a considerable tactical advantage. At the theatre level, Link 16 allows decision makers in the battle space to see a wide variety of ISR sources such as a JORN generated radar picture or the contacts generated by a platform’s RWR. This information distribution network will provide the RAAF with a near complete picture of the battle space particularly when the quality of the sensors feeding it is considered.

The ground component to this information gathering and distribution network is being implemented under AIR 5333 Vigilare ground based air defence system. Vigilare is a significant upgrade to the existing Command, Control, Communications & Computer (C4) systems currently used by the ADF. The system will compile data from a variety of sources such as JORN and Wedgetail and present a manageable and user friendly air picture covering Australia’s area of interest. This will provide what is considered the holy grail of air command & control, a clear and comprehensive picture of the battle space. This C4ISR platform will enable command to manage the battle space in a far more efficient manner, allowing the full potential of the ADF’s sensor systems to be utilized.

The combination of a world class information gathering and distribution network and extremely capable people, missiles and platforms will provide the ADF with an integrated air combat system without peer in the region.

Tactical Implications

State on state conflict is a systems based event, therefore the implications of this vastly improved air defence system are extremely significant and wide, ranging from the tactical to the strategic. Perhaps the greatest advantage of an extensive information gathering and distribution network is the massive improvement in situational awareness, battle space management and command decision making. The amalgamation and presentation of information provided by theatre wide ISR platforms as capable as Wedgetail and JORN have an enormous force multiplier effect. JORN will allow interception of intruding strike packages at maximum range, allowing engagement outside the threat cruise missile envelope. This capability does to an extent replace the need for a high speed interceptor. The RAAF’s maritime strike capability is also vastly enhanced by this system; it allows accurate threat assessment of enemy fleet operations, the utilization of the most effective strike profiles and the system can even conduct some battle damage assessment, all from the Australian mainland. By utilising a clear air and sea picture through out the sea-air gap, the ADF can utilise limited assets to the full. Realistically conducting an offensive campaign in JORN dominated battle space is not an attractive proposition for any of the global powers and is arguably not even realistic for any regional power.

The effects of information dominance provided by such an information gathering and distribution network are not limited only to theatre wide decisions; on the package level having information superiority is a decisive advantage. The ability to achieve the positional advantage is vital in any BVR or WVR engagement, and fighting within your own sensor footprint is a good way to ensure your ability to do just that. By providing the pilot with precise tracks of targets well beyond their own radar capabilities and the threat’s, you enable them to take the positional advantage in a number of ways, such as taking a missile shot from outside the threat’s radar footprint or from a position of altitude or kinematical advantage. In effect you allow the package to always fight on its own terms, and even in a superior platform prosecuting an engagement from a position of significant disadvantage is likely to be your demise. If the target has been engaged from outside their radar footprint, and has no AEW&C support, it’s likely the first detection of a threat would occur when the missiles radar seeker started emitting, which is far too late.



NCW concept






The effect of information distribution between platforms also has a significant effect on the employment of BVR missiles. Currently all BVRAAM’s are not truly fire and forget weapons when being used at long range. Although the R-77, PL-12/SD-10, MICA and AIM-120 series all have an inertial navigation system that can guide the missile unaided, without constant updates from the launch platform at significant ranges the disparity between the projected position and actual target track drastically reduces the probability of a kill. Therefore the launch platform has to illuminate the target for much of the missiles flight which severely limits options to manoeuvre; this significantly increases the counter engagement threat. The combination of Wedgetail, Link-16 and AIM-120D will allow the launch platform to make 150km+ ranged missile shots without using its radar as the fire control device, reducing the chance of RWR/ESM detection to near zero, achieve positional advantage, and manoeuvre virtually as soon as the missile has left the rail. The platform that is not part of a similar information gathering and distribution network will be at a severe disadvantage; prosecuting an engagement on the enemy’s terms, against a target that is rapidly manoeuvring while their own manoeuvre options are severely limited, again if the enemy launch platform is detected at all.

With the addition of the F-35A to the RAAF’s order of battle a LO platform will be added to this already formidable air defence system. With a radar cross section of less than .001 M2, contemporary radar detection levels are reduced to tactically insignificant levels. Therefore the F-35A will be able to take AIM-120D missile shots directly in front of a threat platform within what would normally be its radar footprint. This also applies to threat AEW&C platforms, LO renders them practically useless severely limiting the capability of any competing information gathering and distribution networks.


F-35A Joint Strike Fighter






The decisive advantage integrated networks provide is obvious, and once in place ensuring the integrity of your network and disrupting the enemies becomes paramount. This dual task falls primarily under the dark art of Electronic Warfare. In addition to Electronic Intelligence (ELINT), EW can be roughly divided into two major elements; disrupting the enemy’s communications and sensor capability or ECM, and keeping your sensor performance and communications intact or ECCM. Both of these capabilities are being significantly upgraded under the current modernization program.

The AN/APG-79 has a significant ECM capability that is being developed by Raytheon under the USN’s spiral development program. The extremely precise beam control and frequency modulation combined with the radar’s power output mean it can act as a very effective jammer, and according to the USN is achieving extremely substantial EA effects at “tactically significant ranges”, which would imply comparable distances to a BVR missile engagement envelope. This EA capability is intended to degrade radar capability at stand off range and interrupt data links.


An/APG-79 AESA








Although still in early development the latent EA capability of the baseline F/A-18F BII is significant, and any future software upgrades developed to exploit it will surely migrate to the RAAF fleet. A comparable capability will be provided in the F-35A’s EW suite utilising its AN/APG-81 AESA radar. In addition to the EA capabilities of the baseline Super Hornet Block 2, there has been a notable level of interest in the dedicated EW variant, the EA-18G Growler. Fitted with the AN/ALQ-99 EW system the Growler can simultaneously produce EA effects on several different frequencies with a much higher power output and range. This variant was mentioned by the Defence Minister Fitzgibbon in a recent press release announcing the continuation of the F/A-18F acquisition indicating a significant level of interest from the Ministry of Defence. The extremely complicated LPI scan techniques used in 3rd gen AESA and MESA radars give them very effective ECCM capability, the sophisticated nature of their beam and frequency modulation make them very difficult to effectively jam. Additionally Link 16 has a very effective frequency hopping capability that provides significant resistance to active jamming. EW will always be an ever evolving battle between ECM and ECCM, and thanks to the depth of the strategic alliance with the US, the ADF will have access to their ongoing EW programs which are the most extensive and well funded worldwide.

In a rapidly evolving strategic environment the construction of a world class information gathering and distribution network as the foundation of lethal integrated air defence system is a key to the ADF’s ongoing military superiority in South East Asia. Once all of the elements are in place information dominance throughout the sea-air gap is virtually guarantied, and the RAAF’s lethality will improve accordingly. The ability to apply maximum combat capability at the appropriate point through a clear air picture, to take EM cold, AEW&C cued BVR missile shots from an advantageous position then rapidly egress or manoeuvre, and degrade enemy radar performance and disrupt communications will allow the ADF to dominate practically any engagement, regardless of individual platform capability or deficiency. This only partially illustrates the importance of the integrated system when evaluating aggregate capability, and the partial futility of platform centric analysis. The preservation of truly capable people, information dominance and organization wide improvement is the key to maintaining the RAAF’s capability edge, and it is a goal that we must constantly strive to achieve.

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