Training for the Underwater Threat.

There can be few military situations to equal the `cat and mouse' scenarios played by the hunter and hunted in anti-submarine warfare. Cunning is required by both, but the better-trained crew could well decide the victor, or more precisely the skill of a sonar operator could spell the end of a submarine threat. Or allow it to escape to pose a threat another day.

While nuclear-powered submarines toting intercontinental ballistic missiles obliged Cold War protagonists to hone their anti-submarine warfare skills, the `new order' that closed the 20th century did little to reduce the submarine threat. On the contrary, a growing number of countries have decided to add an underwater capability to their navies. For some, this poses a serious challenge in terms of training, while neighbouring countries will need to develop countermeasures.

The delivery of Kilo class submarines to Iran is a prime example in which a change in the balance of power has led other Gulf navies to look to their ASW defences. Southeast Asia is another region in which submarine fleets are set to increase, demanding appropriate new training facilities in support of such developments, as well as the corresponding sonar training support.

Fortunately, new developments in training aids have brought lower-cost solutions to the market. For example, the Acoustic Systems Trainer (AST) for sonar produced by Feedback has provided the Royal Navy with hands-on training. Claimed to be the only commercially available system for teaching real-time sonar within a laboratory or classroom, the AST overcomes previous requirements for a large water tank to achieve measurable data.

The system comprises an AST console, an acoustic tank measuring just over one metre in length and half as deep, a variable speed target transport system, a selection of active and passive targets and reversible transducers. Hydrophones are used to pick up the very low-level noise and signatures of the passive targets. Entering service in 1997, the seventh and final system was delivered last year.

However, navies with long experience in fielding ASW platforms continue to employ a range of sophisticated training systems, ranging from operator simulators to self-propelled acoustic targets.

Simulation in the Water

For example, thousands of the Mk 39 expendable mobile ASW training target (Ematt) produced by Sippican have been used by the United States Navy since 1993. Compatible with all sonobuoys, sonars, towed arrays and Mad systems, the Mk 39 has also been supplied to several foreign navies. Originally developed by Westinghouse, the self-propelled acoustic trainer (Spat) in its Mod 1 form is today a Northrop Grumman product. In contrast to the Ematt, the Spat is recoverable, and can be turned around within 30 minutes to provide realistic ASW training for operators using either passive or active techniques. Up to 50 planned exercises can be preprogrammed into the Spat.

ECA, Whitehead and Thomson Marconi are among the European companies that have also developed submarine target systems but the Subtrack range of sonar targets produced by Gearing & Watson is already in service with the navies of ten countries.

Simulating Sonar Displays

Although it is cost-effective to generate underwater noise sources to replicate submarines, it is the interpretation of those sources that closes the loop in the training process. A number of companies, including those producing ship-mounted and helicopter-borne dipping sonars have also developed training simulators.

Both Lockheed Martin and Raytheon have produced on-board sonar trainers, the former including systems installed in Trident class submarines, while the Raytheon systems have been installed in a number of US Navy vessels ranging from frigates to cruisers. Raytheon has also supplied sonar trainers to the US Navy Fleet Anti-Submarine Warfare Training Center in San Diego.

Now part of Alenia Marconi Systems (AMS), the British part of this Anglo-Italian joint venture developed the Mandarin Solo as a desktop interactive system for the provision of real-time exercises. In service with both British and American forces, this is a low-cost PC-based simulator that does not require equipment-specific hardware, so it can be easily used in classroom training.

Adaptable to both active and passive versions, Mandarin Solo-Plus can be integrated with other Computer-based Training (CBT) programmes. The Alenia Marconi Systems sonar operator trainers are fully interactive with the dynamics of the platform scenario and ocean model, thus ensuring realistic detection probabilities and the tracking characteristics of the user's region. The company's product line includes onboard trainers which may eider make use of existing operations room displays or can be PC-based.

STN Atlas is among the many suppliers of sonar systems as well as training support in the form of ASW operator stations. These systems form a part of a replica Combat Information Centre (CIC) in which visual and acoustic presentations are given alongide radar, weapon data and combat situation inputs in a de-brief theatre.

Kongsberg Defence & Aerospace and its forebears have equipped Norwegian and Swedish Navy training schools with multibeam sonar simulators covering both identification and classification applications. The user-configurable consoles can act as subsurface. surface or air platforms.

Thomson Marconi Sonar is another company that has developed training aids to support its products. Bringing together some 50-plus years of experience as major players in ASW fields, the training support ranges from CBT systems through generic simulation to dedicated simulators that are exact replicas of actual equipment. Indeed, the company also offers at-sea training systems that include a towed source for training sonar operators, as well as a reusable low-cost target designed to run along a preset course.

Created to run on a network of standard PCs, the Atlantis Action Speed Tactical Trainer (ASTT) makes extensive use of cots technology to provide sophisticated yet affordable simulation. The performance of hull-mounted, variable depth and towed-array sonars can be accurately replicated.

Finally, Russia has not neglected to provide training devices in support of its warships; the CRI Granit company having developed a range of simulators replicating sonar and other combat crew consoles.

Outsourcing and Third Party Training

In an endeavour to cut training costs, some countries have taken to contracting out some aspects. In particular, the delivery of training to the personnel of other navies, or to warship customers may be effected via a commercial organisation. For example, the British company Flagship Training is a joint venture between Johnson Controls, BAE Systems and Vosper Thornycroft, which together offer a wide range of naval training. However, Flagship is essentially an arrangement between the commercial companies and the Royal Navy's Recruiting and Training Agency. Much of the training -- including its active/passive sonar analysis courses -- is provided by Royal Navy personnel or by Flagship's own instructors working to RN standards.

Sonar training has been provided by Flagship to naval personnel from Saudi Arabia, Greece, New Zealand and Sweden. Meanwhile, operational training has long been a service provided by Navfco, the French Navy's service contractor. ASW instruction for the United Arab Emirates Navy Super Puma crews being a typical example of sonar training from this source.