Weapons: Missiles a big hit | ADM Sep 08
The RAAF will soon deploy two different short range air-to-air missiles, either one of which could eventually be selected to arm Australia’s Joint Strike Fighters when the time comes.
Julian Kerr
Acquisition of the F/A-18E/F Super Hornet will see a further missile type added to the RAAF’s inventory, reducing program risk but complicating the task of deciding what eventually will be the standard weapons fitout for the F-35 Joint Strike Fighter.
This follows a Defence decision that Australia’s Super Hornets will mirror the existing capabilities of the F/A-18E/Fs now in service with the US Navy, thus avoiding costly integration issues and any unnecessary delays to the scheduled in-service date of 2012.
The Super Hornets will therefore be deployed in Australian service carrying Raytheon’s AIM-9X Sidewinder short range air to air missile instead of the MBDA AIM-132 Advanced Short Range Air-to-Air Missile (ASRAAM) that now equips the RAAF’s F/A-18A/B “classic” Hornets.
Ironically, ASRAAM was selected by the RAAF in 1998 in preference to AIM-9X, notwithstanding the time and expense needed to integrate the European missile onto the Hornet.
Although ASRAAM’s integration process went relatively smoothly and Initial Operating Capability (IOC) was achieved in 2002, this was in marked contrast to the problems emerging at that time with the integration onto the RAAF’s fleet of 23 F-111Cs of the AGM-142E Have Nap standoff air to ground missile.
Selected in 1996, the AGM-142E eventually took 10 years to reach I0C, and will be withdrawn from service along with the F-111s in 2010.
While that integration process was a scarring one for Defence, many of the lessons learned are now being applied to the integration of Lockheed Martin’s AGM-154 Joint Air to Surface Standoff Missile (JASSM) onto the RAAF’s F/A-18A/Bs.
This is thought to be the only early-model albeit upgraded Hornet fleet on which the 370-km range JASSM will be carried.
With the USN having withdrawn from the JASSM program in 2005 in favour of Boeing’s Harpoon-derived Standoff Land Attack Missile-Expanded Response (SLAM-ER), it seems unlikely though not impossible that the RAAF, as the only other operator of the F/A-18E/F, will sole-fund the missile’s integration onto its own Super Hornets.
Instead, the missiles will be redeployed from the Hornets to the RAAF’s planned JSF fleet when the first aircraft enter service around 2015.
Options
The Super Hornet is, however, cleared to carry the AGM-154 Joint Standoff Weapon (JSOW), the extended range version of which could be considered for future RAAF service.
This powered development of the 483 kg unpowered glide weapon will hit targets up to 550km distant and will cost about US$350,000 – significantly less than the price of a JASSM.
Given the complexities involved in weapons choice and integration, it’s worth examining the official rationale behind both.
According to Defence, each current or future capability requirement endorsed by government is then developed into a costed, defined specification derived from considerations such as future operational concepts, future technology, and current and emerging force structure.
Weapons typically involve the consideration of host platform role and capability, how the weapon contributes to platform effectiveness, and the range of target types, defences and threat platforms now and in the future.
In developing options for government on major acquisitions, Capability Development Group takes into account Defence Intelligence Organisation threat assessments, war gaming, industry studies, and technical studies by the Defence Science and Technology Organisation (DSTO).
The DSTO studies compare weapon effect and force mix options using computer models.
Ultimately, cost and risk are key elements of any acquisition decision.
Weapons already integrated onto an ADF platform or prospective platform, and which meet the capability need, may represent better value for money.
Nevertheless, the risk of integrating weapons onto platforms may be accepted when this is necessary to provide the required capability.
Acquisition of the AGM-142E pre-dated the two-pass Kinnaird project approval process, which ensures Defence now has a better understanding of the likely risks associated with acquisition and integration activities before complex projects are approved.
The problems with AGM-142E arose not from physical integration with the aircraft but from data management issues.
In the case of JASSM, Defence says that Australia chose to be the first country to integrate the missile onto the F/A-18 A/B “because this weapon provides the combination of range and low observability needed to conduct strike missions outside the engagement ranges of the hostile air defence systems expected in the future”.
JASSM was named in February 2006 as the preferred solution for the Air 5418 follow-on standoff weapon requirement, beating off competition from EADS’ Taurus 350 and SLAM-ER.
Although the initial concept was to equip both the F/A-18 Hornet and the AP-3C Orion, it was later decided to reduce overall risk and cost and equip only the F/A-18A/Bs.
JASSM specs
A 1,020 kg subsonic missile with a stealthy airframe and a penetrator/blast fragmentation warhead, JASSM can be released in virtually any type of weather.
Guidance is via a GPS-assisted inertial navigation system with an imaging infrared seeker used for target recognition and terminal homing.
A data link enables the missile to transmit its location and status during flight.
Although development of JASSM began in 1995, the program came close to termination last year because of cost increases and a number of unsuccessful test flights where the missiles either missed the target or the 454 kg warhead failed to detonate properly.
However, on 2 May this year the US Department of Defence announced that it would resume acquisition of JASSM after adjusting production plans to account for cost and schedule overruns.
A month later the USAF ordered another US$107 million worth of missiles, bringing its total to 1,053.
Meanwhile the Australian integration program passed another milestone with the successful release of a JASSM Separation Test Vehicle (STV) from an F/A-18 at the Jervis Bay range in April.
The trial demonstrated that the aerodynamic flow permitted safe separation of a missile from the ARDU (Aircraft Research and Development Unit) test aircraft.
The STV was released under operationally representative flight conditions and delivery manoeuvres and transmitted separation data to a telemetry ground station.
The missile’s self-destruct mechanism was then deliberately triggered in mid-flight to ensure range safety.
Further flight tests will progressively build confidence that JASSM can be launched and operated safely over the necessary range of flight altitudes, speeds and manoeuvres, with IOC scheduled by the end of 2009.
Such flight tests are the high profile elements of a complex process that involves much more than simply integrating the missile with the platform.
The technical and operational issues that arise from bringing a new weapon into service are determined from analysis of the so-called Fundamental Inputs to Capability (FIC).
These encompass organisation, collective training, major systems, supplies, support, and command and management.
Integration of weapons such as JASSM demands rigorous test and evaluation programs, including wind tunnel testing, computer modelling, and aircraft compatibility engineering, that are needed to evaluate the effect of a new weapon on the flying qualities of a platform before live testing can commence.
ASRAAM history
ASRAAM was selected in 1998 to replace the RAAF’s AIM-9M Sidewinders and was cleared for full operational service in September 2004 after 20 test firings were carried out in the United States and Australia.
The missile features an advanced 128x128 resolution infrared (IR) seeker and the ability to operate in heavy electronic counter measures (ECM) environments.
It receives the target coordinates from the aircraft's sensors (radar and infrared search and track), the pilot's helmet-mounted sight, or even from its own IR imaging sensor in the search and track mode.
The missile has a single blast fragmentation warhead detonated by impact and laser proximity fuze.
ASRAAM was selected over the AIM-9X in part because it was only beginning its service life and so had considerable development potential which could be exploited in collaboration with the UK – to date the missile’s only other user.
MBDA claims that ASRAAM, which has 70 per cent more volume than the AIM-9X, can carry more propellant and has a greater range.
Although billed as a short-range dogfighting weapon, the missile has hit targets beyond visual range, the manufacturer claims.
However, US comparative testing of the two competing missiles concluded that ASRAAM could not compete with AIM-9X in off-axis capabilities.
Although a decision has yet to be made on whether to equip Australian JSFs with ASRAAM or AIM-9X, the UK recently decided on a revised weapons fit for its future JSFs of two internal and two externally-carried ASRAAMs instead of the four previously intended for internal carriage.
Carrying ASRAAM outside the weapons bays will allow passive beyond-visual-range engagements cued either by the missile’s seeker or by the F-35’s infrared search and track sensor.
The external ASRAAM fit, utilising a new “stealthy” pylon on stations 1 and 11, will be common across all three JSF variants and is likely therefore to be of interest to other international customers who would otherwise be tied to the AIM-9X.
Another Australian first was the integration of the AGM-114K Hellfire II air-to-ground missile – the army’s first guided missile - onto the Tiger armed reconnaissance helicopter.
This was completed by Lockheed Martin in June 2006 and was the first time Lockheed had integrated Hellfire II on an international helicopter launch platform.
The program’s success is thought to have influenced a subsequent decision by France to equip its own Tiger attack helicopter fleet with the same missile, carried on the same M299 all-digital “smart” launcher.
The two phases of integration flight tests began in May 2005 at Woomera and also involved Australian Aerospace, the Defence Materiel Organisation, the Australian Army, Eurocopter, and Sagem, the manufacturer of the Strix roof-mounted sight which in Australian service incorporates a laser designator for Hellfire II.
The series of tests used multiple launch scenarios and various targets to test approaches, ranges, altitudes and speeds, during daylight and nighttime conditions.
They included three lock-on-before-launch (LOBL) and four lock-on-after-launch firings (LOAL), two with live warheads.
In LOBL mode, the missile laser seeker acquires and locks-on to the coded laser energy reflected from moving and short-range stationary targets target prior to launch.
In LOAL operations, the missile is fired in the direction of a long range stationary target and throughout the final trajectory looks for target illumination either from the launch platform or from a separate collaborative laser designator which may be located several kilometres distant.