Aspects of Navy EW programs

Comments Comments

The RAN continues to operate a very diverse fleet of Electronic Warfare equipment; is it too diverse? And should it include an Electronic Attack (EA) capability?
The RAN has, and will continue to operate, a highly diversified inventory of EW equipment in its surface, helicopter and submarine fleets. And while a number of significant EW upgrades are under way, these are not being treated like the airborne systems in Project Echidna, for which an essentially common architecture and core system have been specified. Instead, Navy is acquiring new EW capabilities on a platform by platform basis, evidently with little in common apart from a fleetwide electromagnetic environment.

This seemingly ad hoc approach fosters the acquisition of different EW systems as a function of time and platform requirement, an arrangement that is likely to complicate through-life support and costs. However the roles and capabilities of the fleet elements are significantly different and this may be the reason for the diversity.

For the FFG Upgrade Program, Navy elected to replace the existing Raytheon SLQ-32 Electronic Support (ES) system and issued a new ES specification. Following competitive tendering by ADI Limited, Rafael's C-Pearl ES was selected. In capital ships an ES will be controlled by the tactical data system (TDS), as will be the case with other EW assets such as decoys and an Electronic Attack (EA) system, if fitted. There is also usually a fall-back capability enabling the ES output to be directly connected to the ECCM assets in the event of failure of the TDS.

The C-PEARL ES is a contemporary system with excellent characteristics for the application. It is designed to process sustained signal densities of up to one million pulses per second over the frequency range. The system contains an active intercept file of more than 250 emitters and a threat library of over 5000 emitters. System outputs provide for direct connection to other EW assets as well as to the tactical data system.

C-PEARL is also the first new EW system to be adopted by the RAN for surface ships for many years and logic would suggest that the system should be the preferred ES candidate for the ASMD upgrade for the Anzac-class frigates and for future capital ships. However, the Anzac's Sceptre ES system has recently been upgraded to Thales-Defence Centaur specification, providing a much-needed improvement in performance that may counter the candidacy of C-PEARL for this ship.

The extent of any further impact on the EW installation on the ship, due to the now approved ASMD upgrade is not known, but is likely to be minimal if the White Paper statement that the upgrade would provide only a reasonable level of ASMD is put into practice. Studies by the Navy and DSTO on the electromagnetic environment, operational scenarios and the threats may shed some light on the ASMD EW requirement in a few months' time.

During the early 1990s Navy invested significant funds to bring the SLQ-32(V)2 ES set up to the US Navy's Alpha baseline to make it compatible with the SLQ-32 jammer that, if added, would bring the system up to the (V)5 configuration. Instead Navy bought the Elbit EA-2118 RF jammer, approximating the SLQ-32(V)5's performance. Currently, the SLQ-32(V)2 and (V)5 variants remain the USN's sole surface fleet EW system and the USN has funded Raytheon to refurbish and improve an initial quantity of seven SLQ-32s to be installed on the DDG-51 Aegis destroyers currently under construction.

Observers have questioned why the Navy should select a new ES for the FFG-7s, the youngest of which is only seven years old when, with relatively little effort and reduced cost, the Raytheon program almost certainly could have been joined. Apart from reduced cost this approach would have maintained EW interoperability with USN EW assets for the remaining life of the FFGs.

When the C-PEARL ES was selected for the FFG upgrade, Rafael had hoped that it would be chosen also for the Collins submarines, the same system being applicable to submarines apart from a different antenna. However the RAN selected a Condor ES system for the Collins-class to replace the Argo 740, noting that Condor had by then acquired Argo. Again, critics have charged that the opportunity was lost to begin rationalising the RAN's EW equipment inventory. But whether the logistics synergies between surface ship and submarine variants of C-PEARL were sufficient to challenge a decision made on operational and commercial grounds remains unclear.

In the not too distant future, as new EW systems for ship and submarine upgrades and helicopter and surface ship begin to be introduced into service, the RAN could find itself with a mixture of extant and new EW systems, of about 10 types across the Navy (See Table 1). In addition, surface ships will carry the Nulka active off board RF repeater decoy. Support of these systems will present a daunting task for the Navy, particularly servicing the fleet with updated threat libraries and hardware modifications to cope with obsolescence and new and emerging threats. It may be that the diversity of systems will complicate the effectiveness and operation of the Navy's EW Test System (EWTS), the operation of which was recently awarded to Raytheon Systems Company Australia. (See box).

Of the three principal combatants, the FFG-7 and Collins submarines will get new systems, and the Anzac frigate will get an ES upgrade. The RAN's lone DDG, HMAS Brisbane, is fitted with the now obsolescent WLR-1H ESM system, but the ship will retire in 2002. As an aside, it is noteworthy that the venerable WLR-1 continues its long life in the USN's inventory. The Variant (V)-7 is literally a new system and is now scheduled to continue to be used as the USN's prime shipboard ESM system.

The Fremantle-class patrol boats are currently fitted with the BAE Systems PRISM ESM system, while the RAN's Seahawk and Super Seasprite helicopters will be equipped with the Radar Warning Receiver from the Elisra AES-210 ESM system. The RAN's Seakings now appear to be unlikely to get an EWSP suite from the Echidna project, but perhaps a lower capability variant of the system fitted to the Seahawks and the Seasprites would be a more logical arrangement. An ES capability has yet to be selected yet for the New Patrol Boat, but is considered likely to be a new system.

The RAN's original plans for both the FFG-7 Upgrade and the now cancelled Anzac Warfighting Improvement Program (WIP) included both ES and Electronic Attack (EA) capabilities as part of their EW suite, as well as Nulka, and the hard kill Evolved Sea Sparrow Missile (ESSM). Additionally, FFGs carry the Phalanx automatic radar-directed Close-in Weapon System.

Both classes of ship are to be fitted with Nulka and ESSM, a combination that the Navy evidently believes provides adequate self-defence protection for them, as there are no plans to fit them with an EA capability. Nulka and ESSM will also be widely used by USN ships for self-protection along with the AN/SLY-2 (Advanced Information EW System). For example, the new Wasp class amphibious landing platforms are scheduled to be fitted with AN/SLY-2 with Nulka soft-kill, testimony to the latter's effectiveness.

The decision by the Navy not to install EA is at odds with the findings of other navies and airforces. Self-protection systems such as Nulka and ESSM are expendables used during a terminal engagement, although the maximum effective range of ESSM is close to line-of-sight. This is not the case with an EA. Advocates of EA in the RAN and DSTO maintain that a modern solid state jammer significantly contributes to a ship's self-defence capability. Such an EA system is similar in cost to four ESSMs, worth some $800,000 each, a figure that probably equates to the cost of a single anti-ship missile engagement.

Modern EA capabilities include very long and short range jamming over a selectable arc in azimuth, denial of the frequency spectrum an aggressor is using for attack, through frequency agility over a wide band and the use of jamming waveforms radiated by the EA system. The selective use of these capabilities counter the agility of an aggressor's radar and fire control systems, including active radar homing missiles. For the last capability the ES system analyses an aggressor's signal characteristics and sends them to the EA system where the information is used to develop in real time special countermeasures waveforms in a techniques generator. These waveforms are then output to modulate the EA transmitters to counter the countermeasures the aggressor may attempt to implement. The technique is now widely used in airborne RF jammers.

However critics of an EA system are keen to point out that EA will not combat E-O guided missiles, which is true, but that is also true of Nulka until or unless it is given the capability to become an intelligent flare.

Table 1. Current and Future RAN ES systems

Platform Current system New system
Collins Argo 740 Condor
FFG-7 SLQ-32(V)2 C-Pearl
Anzac Sceptre A Thales-Defence Centaur
Seahawk N/A AES-210
Super Seasprite N/A AES-210
Seaking N/A TBA
Fremantle PRISM N/A
New Patrol Boat N/A TBA

By Fred Haddock & Tom Muir, Canberra

RAN selects Raytheon for EWTS - The Royal Australian Navy has named Raytheon Systems Company Australia as preferred tenderer for the provision of Electronic Warfare Training Services (EWTS) to enhance the operational effectiveness of Navy fleet units.

Five commercial offers were evaluated for the $60 million, 10-year contract. The decision, under the Defence Commercial Support program, is expected to provide an updated EW training capability appropriate to contemporary EW technology on a cost-effective basis.

The successful contractor will be required to provide, on a privately financed basis, the airborne platform, equipment and all resources needed to deliver the full training services around Australia and, if required, to units deployed in the South East Asia region. This will replace the RAN's current EWTS capability based on two HS 748 turboprop transports.

Subject to successful negotiations, Raytheon was scheduled to commence a phase-in of operations in early 2001, with full service delivery by mid-2001.

By Gregor Ferguson, Adelaide
comments powered by Disqus