Indian Army has a long standing requirement of replacing the existing fleet of 105 mm, 130 mm and 155 mm FH77B 39 calibre gun with 155 mm x 52 calibre gun to keep pace with the worldwide trend of artillery guns.

Advanced Towed Artillery Gun System (ATAGS) is a fully indigenous 155 mm x 52 calibre towed artillery gun system developed in mission mode by DRDO as a part of Artillery Modernisation program of Indian Army.The ATAGS is the maiden initiative by DRDO in the development of long range artillery guns for the Indian Army by completely indigenous development efforts. Development of ATAGS is a mission to build capability and infrastructure for Modern Gun system and create a national resource for capacity to build the most advanced gun system worldwide.

Work Content & Technological Achievements

ATAGS is a good example of synergised efforts resulting in a successful product ‘right first time’ in a record time. Many DRDO labs contributed in the successful realisation of the ATAGS. Technological strengths and expertise of each lab was used to the fullest extent to develop various critical technologies. The system is configured with All Electric Drive technology, for the first time in the world, that will ensure maintenance free and reliable operation over longer periods of time. The automation will enable five-round Auto Multiple Round Simultaneous Impact (MRSI), automatic shell and charge loading, ramming with automatic gun deployment. The automation of these operations also facilitate higher rate of fire, fast coming into/out of action in the war scenario. It is equipped with an Integrated Fire Control System consisting of inertial land navigation based Automatic Gun Alignment and Positioning System, Muzzle Velocity Radar and a Ballistic Computer to carry out online computation. Gun system is also integrated with a Thermal Imager to impart night firing capability in direct fire mode. The system is configured with a Battery Command Post (BCP) that will command and control a battery of six to eight Guns over radio and line. The gun battery, ordnance and recoil system, breech mechanism and muzzle brake have been manufactured by the private industrial partners.

With the active participation of leading private Indian industry, the armament system for ATAGS was test fired and proved successfully on 17 June 2016. The Gun Structure and Automotive System (GSA) and Gun Automation and Control System (GAC) have been developed by industrial partners. ARDE helped in the integration of the system. This resulted in a robust gun, which proved its design strength in December 2016, the automotive system and undercarriage for the gun that comprises a power pack, drive system, suspension system, braking system, cooling system and the traction system was also successfully tested. It was imperative for ATAGS to adopt a new strategy for automotive system for enhancing the mobility, deployability and powering the complete drive system including the gun automation. A compact high efficiency customised 110 kW Diesel Engine fitting to the stringent emission norms have been successfully realised. This is followed by a compact, high rigidity Power Take Off (PTO) for powering the wheel transmission, driving the 12 kW alternator, Charging of Battery Bank, and power the hydraulic drive for auxiliary operations such as cooling system, caster wheel operation, deployment of Trails, Central Platform, draw bar actuation. 

The unique technology incorporated by the team is the use of walking beam suspension as against the conventional hydro gas suspension as well as independent drive to all four wheels. As a result of development and incorporation of all these technologies, Self Propelled mobility 18 km/hr, 360 degree pivotal turning, turning radius of less than 25 m and climbing at 18 degree gradient could be achieved. The indigenous development of optronic sight, dial sight, and telescope and muzzle bore sight was a big task but the incorporation of these technologies was important for enabling the gun for direct fire role. The complete optronic sight consists of Cooled Thermal Imager, Laser Range Finder, and CCD-based Daylight Camera. This has a identification range of up to 2 km and detection range of up to 10 km. All these have been designed, developed and implemented through indigenously available sources. Centre for Artificial Intelligence and Robotics (CAIR) and Defence Electronics Application Laboratory (DEAL) are responsible for design and development of advanced communication and Fire Control System for ATAGS. The communication system comprises a complete package solution incorporating Tactical Computer (TC), Voice and Data Communication Unit (VDCU), and Software Defined Radio (SDR). All the hardware and software have been designed and developed through indigenous sources. All these communication equipment have been tested with the gun system and has a standoff distance of 5 km as per user’s requirements. The fire control software for ATAGS including trajectory computation module has been designed, developed and integrated in the tactical computer. The complete development has followed protocols for seamless integration and induction of the ATAGS in the Armed Forces.Proof & Experimental Establishment (PXE) is the sole agency for complete testing and evaluation of the ATAGS and its sub-systems. The all round support during the trials expedited the development and many systems could be realised in time.

The instrumented support and the analysis of the critical data for the design were provided by PXE. Private industries also played a vital role in realisation of the system and emerged as strong development partners of DRDO. Various private industries strengthened their resources for future requirements and enhanced their capabilities also. ATAGS will be a game changer and basis for future artillery development programmes. It will lead the way to the development of its variants such as Tracked and Wheeled Mounted Gun System (MGS) and Self-Propelled (SP) Artillery Gun Systems. The establishment of manufacturing and integration facility for large calibre artillery gun, foreseen during the development of ATAGS, will be the most significant task to move closer to the self-reliance in this area. All these efforts will bring India in the league of few nations having fully indigenous artillery gun system.

World Record Range Achieved

Internationally, the ATAGS is not only at par but also excels in many areas. The development time for realising the first two prototypes is the fastest in the world. Within first four years of the project the integrated gun system could be realised from the drawing board to the field level. The range achieved by ATAGS is highest ever range achieved by any artillery gun in this category. The 48 km range achievable by in-service ammunition is possible by ATAGS. The all electric drives in the gun system is the first used and demonstrated in any ATAGS and tried nowhere till date. Mobility of 20 km/hr is comparable with the guns available in this category world-over. The firing of zone 7 Bi-Modular Charge System (BMCS) is possible only in ATAGS as compared to firing up to zone 5 by M777 and zone 6 by other international contenders. Most of the specifications such as range, mobility, fire control system, sighting system, etc., from the draft PSQR have been achieved or exceeded by the ATAGS. The two integrated ATAGS systems (G1 & G2) after the successfully dynamic strength trials have undergone series of Ballistics Confirmatory Trials at PXE and Technical Trials at PFFR, Pokhran. During the Pokhran trial, ATAGS achieved the world record milestone of attaining highest ever range of 38.5 km and 48 km with in-service ammunition as compared to 30 km and 40 km being achieved by the contemporary artillery guns worldwide. Recently, these gun systems have also successfully undergone mobility and firing trials at High Altitude Area, Sikkim Field Firing Range (SFFR), during January 2018. Both the gun systems were taken in towed and self-propelled mode till the firing point at Menla. The systems fired excellently well in cold climatic conditions.

Current Status & Way Forward

Both the ATAGS Gun Systems would be subjected to PSQR compliance trial at PFFR, Pokhran, during June 2018. Apart from the two systems, orders have been placed for realisation of two more Gun Systems G3 and G4, from each development partners. Parallel to this, proof of ordnance and recoil systems is also being carried out. Results of trial outcomes of G1 and G2 are being imparted continuously for system refinements of G3 and G4, which would undergo User Assisted Technical Trials (UATT) and consequently User Trials (UT) in September 2018. Additionally, an order for realisation of three guns each from development partners, has been placed. These gun systems will be utilised for user exploitation in different terrains. (With inputs from DRDO)

Our Bureau