India’s Cruise Missile Programme Updates

Re-inventing the wheel is a futile and time-consuming process for countries like India, especially when there are a select few friendly, highly industrialised countries that are more than willing to share their expertise with India’s military-industrial entities and co-developing re-engineered, customer-specific weapon systems that are required in large numbers by India’s armed forces. Such a business practice thus cuts short the gestation timeframe required for fielding advanced weapons on multiple platforms, since all their R & D challenges have already been overcome before, and all that is required to be done is to customise or re-engineer them for complying with the qualitative requirements of their respective Indian end-users. Three such weapons that are now under co-development comprise the Nirbhay family of land-attack cruise missiles (LACM) and the BrahMos-NG supersonic multi-role cruise missile (MRCM) being co-developed with Russia’s JSC MIC NPO Mashinostroyenia (NPOM), and the smart anti-airfield weapon (SAAW) being co-developed with Israel’s RAFAEL Advanced Defence Systems.

Nirbhay LACM Explained

The Nirbhay is a subsonic LACM designed to fly at subsonic speeds to neutralise targets of interest deep inside the adversary’s territory in the early days of a conflict. This project was conceived back in 2003 as a ground-launched cruise missile (GLCM) and air-launched cruise missile (ALCM) for the Indian Air Force (IAF) and as a warship-launched/submarine-launched cruise missile (SLCM) for the Indian Navy (IN). An inter-governmental agreement inked in mid-2005 between India and Russia saw the formalisation of industrial partnerships between India’s Defence Research & Development Organisation’s (DRDO) Bengaluru-based Aeronautical Development Establishment (ADE) and Russia’s Novator OKB, and between India’s Hindustan Aeronautics Ltd (HAL) and Russian engine manufacturer JSC NPO Saturn. Subsequently, Novator OKB transferred the design data package of its 3M-14E LACM to ADE for re-engineering purposes, while JSC NPO Saturn began shipping 12 fully-assembled and ready-to-install 37-01E turbofans for the Nirbhay’s flight-test programme, and this was to be followed by the supply of an additional 600 turbofans in knocked-down condition to HAL for final assembly. Full-scale prototype development work commenced in early 2007, with the ADE being designated as the nodal systems house for R & D along with ASL (Hyderabad), RCI (Hyderabad), HEMRL (Pune), R & DE (E) (Pune), TBRL (Chandigarh), ITR (Balasore) and GTRE (Bengaluru) as sub-systems re-engineering partners. Phase-I of the project focussed on the development of Nirbhay’s ground-launched version.

Any cruise missile mission consists of pre-launch, launch, cruise and terminal phase. The pre-launch mission phase deals with mission planning, waypoint selection, on-board mission computer’s algorithm, complete missile system checkout, and the fire-control system. The launch phase starts with booster fire and shaping the trajectory with the help of thrust vectoring and ends with a configuration suitable for cruise phase. The cruise missile configuration is basically an aircraft-like configuration that flies along the various waypoints using autonomous waypoint navigation. At the end of the cruise phase, the missile performs a terminal manoeuvre to home to a target at the desired attack angle. 

The unique selling point of the LACM includes:

• Long-range missions at very low altitudes

• Autonomous mission and trajectory control through waypoint navigation

• High degree of loitering capability

• High degree of range scalability

• Deployable from multiple platforms

• Designed to carry desired warheads on targets of interest

• A cost-effective weapon delivery platform

• Ability to attack the target from any desired direction

The Nirbhay is configured to achieve various mission phase requirements. This bank-to-turn missile was designed with a low wing and four all-moving fins for stability and control. The missile, designed with a high degree of modularity, consists of seven sections to house the seeker, warhead, on-board avionics, fuel and air-intake section for the turbofan engine, and the expendable booster section. This configuration is optimised for low-altitude flights though it delivers desired performance for the full flight envelope. The airframe was designed by Novator OKB for modular fabrication and integration, predominantly with light aluminium alloy and composite materials. The airframe was designed considering the ‘g’ loads experienced in the boost and cruise phases. The airframe construction uses glass-fibre and carbon-fibre as reinforcements in fabric form, epoxy resin system as matrix, and acrylic foam (Rohacell) is used as a core material. Fabrication uses wet layup, pre-pregs and matched die-moulding process. The bulkheads and longerons are also made of aluminium alloy. The structural sizing of the airframe was carried out to satisfy strength, stiffness and stability criteria as well as dynamic and aero-elastic requirements as stipulated in applicable aircraft standards and military standards.

The Mobile Articulated Launcher is configured for transportation, emplacement, erection, activation and the launching of missiles. In addition, the launcher also houses the main and standby power-supply systems, the fire-control and checkout system for up to four missiles, intra-communication system for communications with the combat management system and other associated ground-support systems equipment. The launcher is built with a rail-guide, on which the missile-lugs travel to ensure safe clearance. The current launcher, fabricated by Larsen & Toubro, is a prototype to be used for development flights of the missile. The actual launcher will be developed against specific requirements of the users. The Fire-Control & Checkout System (FCCS) is intended for automatic checkout, preparation before launch and launch of the missiles. The FCCS consists of a launch console, which is the central controller that coordinates the activities of all the sub-systems. Interaction of the launch complex with the articles is facilitated via the missile interface unit. The launch complex can be also be operated from a remote console. Mission planning is an essential activity and it deals with the collection of relevant information on target, terrain, obstacles, threats, the missile’s capability, and the ground-support capability to achieve maximum kill probability.

The wing is folded and kept inside the fuselage, held by the initial locking mechanism. The wing shutter opens during the boost phase upon command and after the wing is deployed the door closing mechanism is initiated to close the cut-out provided in the fuselage, resulting in reduced missile drag during the cruise phase. The wing deployment systems is attached to the centre bracket of the wing and an attachment bracket has been welded with the fuel tank with a provision to fix a strut, which in turn receives the wing centre bracket. The basic mechanism is of single slider crank-type. The active force generated by a pair of pyro-cartridges is converted into torque for rotating the wing through 90 degrees. Damper is provided in the mechanism for energy absorption during deployment phase. The mechanism is provided with two types of locking mechanism and stopper to keep the wing in position after deployment. The submerged air-intake section consists of the air-intake duct, which starts as a hole in the belly of the missile and guides the air into the inlet section of the engine. The length, ramp angle and lip-radius of the submerged air intake is designed to meet the constraints on distortion levels and pressure recovery.

The requirements of long-range precision navigation are achieved using redundant satellite-aided navigation system using the IRNSS constellation. The primary navigation system is based on three sets of ring laser gyro and accelerometers (supplied by Israel Aerospace Industries’ TAMAM Division), which produces unaided and aided navigation information at regular intervals through a MIL-STD-1553B digital avionics databus. The secondary navigation system is based on three sets of MEMS gyroscopes and accelerometers that produce similar information as that of the primary navigation system. In case of failure of on-board inertial sensors, the primary navigation system uses equivalent information from the standby system till the second failure. Upon second failure, the on-board control system uses the secondary navigation system’s information for its control loop closure. The redundant navigation systems ensure the desired nautical mile per hour accuracy at the start of the missile’s terminal cruise phase. The primary launch phase requirement of any cruise missile is to launch vertically through the mobile articulated launcher and to align at any desired direction, meeting the altitude and Mach number constraints at various instants of time. In this phase, the missile transcends four configurations, starting with missile then to a bomb (with fins only) and to a glider with wings deployed and finally an aircraft configuration powered by the turbofan. 

Accelerating the missile from zero speed to the desired speed is achieved by using an expendable solid propulsion booster, housed as a part of the booster section. This section is connected to the main missile using four pyro-bolts, which are initiated for stage separation after booster burn-out during launch. This section houses all the onboard systems essential for thrust vectoring and also a separation mechanism to ensure positive separation of the missile. The booster’s thrust axis is deflected as desired by the thrust-vector control system to generate necessary control forces to achieve the desired launch phase trajectory from vertical to horizontal. The thrust-vector control systems consist of a pair of actuators mounted on a flex-nozzle system to orient the thrust axis in both pitch and yaw planes. The on-board control system compares the state information as measured by the on-board inertial navigation system with desired trajectory, and generates steering commands to the thrust-vector control actuator.

When the missile reaches the desired speed and orientation, the solid propulsion booster is jettisoned using pyro-bolts and retro-motors. The pyro-bolts ensure physical separation of the booster section from the missile and the retro-motors ensure positive separation from the missile. In this phase, the missile is entering the no-thrust zone and it continues till the engine develops full thrust. After sufficient time separation, the wing is unlocked, deployed and locked into its final desired position that turns the missile to a glider configuration. In this phase, the missile is still in the no-thrust zone. After sufficient time separation, the turbofan is started in-flight, which turns the missile into powered aircraft configuration. 

When the turbofan develops the full thrust, the missile exits the no-thrust zone and enters into an unmanned vehicle configuration. The missile is designed to execute the mission autonomously without any external intervention and it also has the ability to reconfigure the flight-control system’s commands in response to different on-board events and failures. The FCSS uses body rates, liner accelerations, attitudes and positions obtained from the RLG-INS for all control loops. Baro-altitude obtained from an air data sensor is used by the navigation system for vertical channel damping and a radar altimeter is used exclusively for low-altitude flights. The four linear fin-actuators are located around the turbofan in a narrow annular space. The desired stability and control of the missile in the cruise phase is achieved using four fin actuators and are individually commanded by the flight-control computer (FCC). 

The FCC is the prime computational hardware that performs the main functions of flight and mission control such as sensor data acquisition, sensor computation, longitudinal, lateral and directional control law execution, and provides the drive signals for on-board discrete events and actuators through 1553B and RS422 databuses. All the flight-control laws, mission control laws and safety logics are coded in strict adherence to DoD-STD-2167A and implemented in the FCC. The cruise phase capabilities of the missile are achieved through autonomous waypoint navigation. In this mode, the missile exhibits its capability to control the trajectory in vertical and horizontal planes while maintaining the desired track. Also, this system is designed with no restriction on the heading change between the waypoints.

The maiden launch of Nirbhay LACM’s ground-launched version was conducted on March 12, 2013 during which it flew for 20 minutes and thereafter deviated from its flight path due to a failure of the on-board MEMS gyroscopes and accelerometers, and consequently its on-board self-destruct mechanism was activated. The second launch was conducted on October 17, 2014 at ITR, Chandipur, and was a big success, with the LACM travelling 1,010km instead of the targetted 800km.These two launches demonstrated several new indigenously-built technologies like automated pre-launch checks, booster-assisted launch phase trajectory control, stage separation in near-horizontal attitude, in-flight wing deployment, submerged air intake for engine and in-flight engine start. The repeatability of these achievements has demonstrated the systematic approach and robustness of the design. 

The second launch also demonstrated complete autonomous mission mode, comprising of cruise phase based on waypoint navigation and the terminal phase. The third test-flight on October 16, 2015 was again a failure. After 70 seconds of its flight, the missile lost control and fell within the safety zone. The fourth flight-test on December 21, 2016 was an utter failure, caused by a wing-deployment problem. After liftoff, the missile started veering dangerously towards one side in less than two minutes. The missile started flying beyond the safety corridor and threatened to fall on the land. So the “destruct” mechanism in its first stage was activated and the LACM was destroyed. It was undoubtedly a hardware failure due to a reliability issue with a component.

BrahMos-NG Explained

BrahMos Aerospace Ltd was established in India through an inter-governmental agreement signed on February 12, 1998 between Russia and India. The DRDO from India and JSC MIC NPO Mashinostroyenia (NPOM) from Russia are the joint venture partners of BrahMos Aerospace, which was started with a capital of US$250 million with 50.5% from the Indian side and 49.5% from the Russian side. JSC MIC Mashinostroyenia comprises eight strategic companies: NPO Mashinostroyenia (Reutov, Moscow), JSC Production Association Strela (Orenburg), JSC Permsky Zavod Mashinostroitel (Perm), JSC Scientific and Production Association of Electro-Mechanic and JSC Makeyev State Rocket Center SKB-385 (Miass, Chelyabinsk), FSUE Avangard (Safonovo, Smolensk), FSUE Ural Research Institute of Composite Materials, or UNIIKM (Perm), NII Electromechaniki (Istra, Moscow) and Concern Granit-Electron (St Petersburg).

Unlike the ground-launched/ship-launched BrahMos-1 and its air-launched BrahMos-A version that can be carried only by the Su-30MKI H-MRCA, the BrahMos-NG (known earlier as BrahMos-Mini) will be lighter and narrower, enabling it to be launched by M-MRCAs like the Rafale, MiG-29UPG and carrier-based MiG-29Ks, and it will also be capable of being launched from a submarine’s 533mm torpedo-tubes.

The entire on-board avionics suite of the BrahMos-NG—which will have a high degree of communality with that on-board the Nirbhay family of LACMs—will be of Indian origin and it is now under development via the cluster of public-sector and private-sector industrial entities that are also involved with the Nirbhay’s developmental effort.

The SAAW Explained

The SAAW is a joint India-Israel project to co-develop an air-launched, standoff EMP-emitting missile, which, for all intents and purposes, will be India’s first operational precision-guided directed-energy weapon (DEW). It may be recalled that in the night of September 6, 2007 in the desert at Al Kibar, 130km (81 miles) from the Iraqi border and 30km from the northern Syrian provincial city Deir el-Zor, a fleet of ten IDF-AF F-15Is conducted OP Orchard, which involved the destruction of a heavy-water reactor then under construction with North Korean expertise and Iranian funding. In that raid, the IDF-AF had used a RAFAEL-developed precision-guided, standoff DEW to shut down Syria’s ground-based air-defence sensors—a move that would go on to be the optimum model for future surgical air-strikes. 

Israel offered to co-develop a variant of this DEW with India on July 7, 2008 during an official meeting in Pune with the DRDO. This was followed by two additional meetings held in Delhi with senior DRDO and IAF officials in August and September 2007. The joint R & D project officially began in mid-2010 and series-production of this DEW will commence later this year, with Indian industrial entities like Bharat Dynamics Ltd, ECIL and the Kalyani Group being involved in this undertaking.   This air-launched, fire-and-forget, expendable DEW, whose main role is to render electronic targets useless, makes use of the airframe of RAFAEL’s Spice 250 rocket-powered PGM, and will have a range of 120km. It is a non-kinetic alternative to traditional explosive weapons that use the energy of motion to defeat their targets. During a mission, this missile will navigate a pre-programmed flight plan (using fibre-optic gyros) and at pre-set coordinates an internal active phased-array microwave emitter will emit bursts of selective high-frequency radio wave strikes against up to six different targets during a single mission. The EMP-like field that will be generated will shut down all hostile electronics. Thus, the whole idea behind such a weapon is to be able to destroy an enemy’s command, control, communication and computing, surveillance and intelligence (C4SI) capabilities without doing any damage to the people or traditional infrastructure in and around it. In other words, it can eliminate a hierarchical air-defence network’s effectiveness by destroying the electronics within it alone, via a microwave pulse, without kinetically attacking the network itself.

For the IAF, this air-launched DEW will be a ‘first day of war’ standoff weapon that can be launched outside an enemy’s area-denial/anti-access capabilities, and fly a route over known C4SI facilities, zapping them along its way, before destroying itself at the end of its mission. Because of its stealthy design, long-range and expendability, it will fly where no other manned airborne assets could and because it does not blow anything up, its use does not necessarily give away the fact that the enemy is under direct attack in the first place. In that sense, it is also a psychological weapon, capable of at least partially blinding an enemy before it even knows that a larger-scale air-attack is coming. The IAF plans to arm its upgraded Mirage 2000Hs, Jaguar IS/DARIN-3 interdictors and the yet-to-be-delivered Rafale M-MRCAs with this DEW and also with RAFAEL’s Spice-1000 PGMs. Unguided test-launches of the SAAW from a Jaguar IS were first conducted at Pokhran in May 2015 to validate the weapons release/pylon ejection mechanisms, while the first powered test-flight was conducted on December 23, 2016. Both the IAF and IN have a stated requirement for 500 SAAWs.