For some years Giat Industries of France and Royal Ordnance of the UK, together with their associated research and development establishments, have been working on the Case Telescoped Weapon System (CTWS).

Details of this and the Giat Industries 45 mm Case Telescoped Ammunition (CTA) Cannon M911 were given in Jane's Armour and Artillery Upgrades 1995-96 pages 14 and 15. The 45 mm M911 is the basis for current CTA International CTWS programme.

CTA International is jointly owned 50/50 by Royal Ordnance of the UK and Giat Industries of France and is based at Bourges, France.

CTA International is supported by parent companies in France and the UK and works in close co-operation with the Defence Evaluation and Research Agency (DERA) in the UK and the Direction des Systemes Terrestres et I'lnformation (DSTI) in France.

The first 45 mm CTWS demonstrator cannon was completed in 1991 with the first prototype being completed the following year.

There were originally three main possible applications for the 45 mm CTWS, the French VAD (8 x 8) member of the VBM family of wheeled armoured vehicles and in the UK, TRACER (Tactical Reconnaissance Armoured Combat Equipment Requirement) and the projected GKN Defence Warrior Mid-Life Upgrade (MLU).

The VAD programme has now been cancelled and a new 8x8 vehicle will be introduced into French Army which will be fitted with a one-person turret armed with a 25 mm cannon and 7.62 mm co-axial machine gun.

The TRACER programme has now joined with the US Future Scout Cavalry System (FSCS) with no calibre for the armament being selected so far. The British Army's projected Warrior Mid-Life Upgrade has now been cancelled.

CTA International is now funding the full-scale development (FSD) phase using their own funding so that by late 2000 a company qualified weapon, four natures of ammunition and feed system will be available for installation in a vehicle platform.

Although most of the development work has been on a 45 mm CTWS, in mid-1997 a decision was made to focus on a 40 mm CTWS and CTA has now built two 40 mm/70 calibre weapons under the designation CT 2000.

As well as developing the 40 mm gun and its associated family of ammunition, CTA International is also developing the associated linkless ammunition handling system.

The 40 mm CTWS uses a rotating breech mechanism and Case Telescoped Ammunition (CTA) which is claimed to be a significant advance on existing technology.

The use of lightweight ammunition case material and the compact shape of the round, which consists of a projectile surrounded by propellant, makes it lighter, safer and easier to handle and also decreases stowage volume.

The 40 mm CT 2000 will have a variable rate of fire of 200 rds/min when being used in the automatic mode and optimised for accuracy of 60 rds/min in the rapid single shot mode.

It will have dual feed, with one normally being used for the General Purpose Round-Tracer (GPR-T) and the other for Armour Piercing Fin Stabilised Discarding Sabot-Tracer (APFSDS-T). The barrel will be fitted with a muzzle brake and the empty cartridge cases will be ejected forwards.

CTA International has already demonstrated a full mission load linear linkless ammunition handling system (AHS). The AHS has been designed and built with the integration constraints of the US Army's Bradley infantry fighting vehicle in mind.

The system, including a 40 mm CT 2000 cannon will fit the current space envelope taken up by the in service The Boeing Company 25 mm M242 cannon and ammunition storage in Bradley.

The system contains two ammunition magazines and has the ability to change natures in less than 3 seconds.

The 40 mm CTWS Remote Weapon Station Concept is aimed mainly at the TRACER/FSCS requirement as it would offer the user significant weight savings compared with a conventional turret system.

These include an overall reduction in weight, decreased electrical requirements, increased crew survivability and simplified NBC and environmental protection. The overall height of the vehicle would also be reduced.

Details of the CTA International 40 mm CTWS Remote Weapon Station Concept are given in the AFV turrets and cupolas section.

In addition to the TRACER/FSCS application, CTA International are also marketing their cannon as the projected UK and Future Infantry Fighting Vehicle (FIFV) programme.

According to CTA International, The CTWS concept can be scaled up or down and other potential applications include support weapons and aircraft cannon.

CTA International has already built the prototype of a 12.7 mm CTWS which fires at the cyclic rate of fire of 4,000 rds/min with an ail up weight of 26 kg.

Two natures of ammunition are being developed for the CT 2000, APFSDS-T with a muzzle velocity of 1600 m/s and GPR-T (General Purpose Round-Tracer) with a muzzle velocity of 1000 m/s. Both of these use propellant provided by SNPE with the empty cartridge cases being ejected forward of the weapon.

The former features a tungsten rod penetrator which during trials has penetrated over 150 mm of steel armour at a range of 1500 m with significant behind armour effects.

Earlier trials of the 45 mm GPR-T used a programme air burst fuze developed by Oerlikon Contraves of Switzerland. For the 40 mm GPR-T application CTA International plans to consider a number of time/burst options, a typical factor will be the performance/cost factor that CTA International is currently conducting. Each GPR-T projectile will have an effective range of 100 mz against upright troops in the open.

Development of the APFSDS-T is running ahead of the GPR-T and any improvements that are carried out to the ammunition must also include a cost reduction. GPR-T rounds have already been fired in a slave weapon and were fired in a complete CT 2000 weapon in 1999.

CTA International is currently concentrating on the actual weapon, ammunition and feed system which they would deliver to the customer for integration into the turret handling system and associated ammunition.

Weapon system qualification is usually a very expensive and time consuming process but CTA International have already taken steps that the complete weapon system will be qualified to all potential users' (France, UK and USA) standards. Data from every firing is being fed to a database already.

CTA International claim that when compared to a conventional cannon, the 40 mm CT 2000 has a 10 per cent less acquisition cost as well as lower overall life cycle costs.

CTA International are already looking at further enhancements to CT technology including a smart HE projectile which, with technology from the guided weapons industry, can give a degree of terminal guidance to the projectile. A potential application could be close in air defence.

Development. Not yet in production or service.