bulletin of defence research and development organisation...

A monthly house bulletin of Defence Research & Development Organisation ■ Vol. 31 No. 7 ■ July 2011ISSN : 0971-4413BULLETIN OF DEFENCE RESEARCH AND DEVELOPMENT ORGANISATION Vol. 20 No. 4-6 August-December 2012

DRDO has made remarkable progress in the field of armaments and made

the nation proud by delivering advanced systems and technologies

to the armed forces. Various types of ammunitions and rockets

developed are in the armoury of the Indian armed forces. Wide

varieties of rocket propellants, high explosive filling for warheads

for Agni, Prithvi, Akash and other missiles have been developed

and are being productionised at ordnance factories. DRDO

has also made significant contributions in indigenisation of

small arms, mortars, RPG's, disposable RL's, mines, bombs,

and ammunition. High energy propellants and explosive

composition required for missiles, guns and warheads have

been successfully developed and technology transferred to

industries.

This issue of Technology Focus highlights some of the

technologies/products/processes developed by the armament

groups of laboratories/establishments of DRDO.

2 August-December 2012

Pinaka Multi Barrel Rocket Launching System

Pinaka multi barrel rocket launching (MBRL) system, named after the divine bow of Shiva, is an all-weather indirect fire free flight artillery rocket system. It delivers accurate and massive firepower at high rate over extended ranges. A battery of six launchers can fire a salvo of 72 rockets. The warheads can be delivered up to a range of 38 km and can effectively neutralise a target area of 1000 m by 800 m. In terms of its characteristics, the system is highly mobile and can attack enemy in depth with strike and counter fire capabilities. Its awe inspiring fire power adds substantially to the defensive and offensive capabilities of the Indian Artillery.

Pinaka can neutralise various types of targets, namely, POL and ammunition dumps, gun positions, wagon lines, communication centers, rocket positions, moving columns of A or B vehicles, forward helipads, surveillance radar, and assembly areas.

Salient FeaturesHigh lethality achieved by optimised warheads u

Battery command post equipped with a rugged u

Pinaka rockets firing a salvo

enhanced tactical computer for comprehensive control of firing mission through secure wireless data link

Automated laying of launchers by powerful u

microprocessor based servo drive.

Automatic gun alignment and positioning system u

(AGAPS) integrated with each launcher for land navigation and launcher orientation

No separate survey team is required for positioning u

and orientation making the launcher autonomous

Shoot and scoot capability enables launcher to u

escape counter battery

Fast coming into action is achieved with the help of u

automated features enabling fast response to call for fire

Matching mobility and logistics commonality by u

use of a common chassis for the family

Precision Guided Munition AvionicsPrecision guided munition (PGMs) are advantageous

over conventional counterparts as these provide increased lethality, stand-off capability, decreased exposure to risk, and reduced collateral damage. Two types of PGMs, have been developed viz., (1)Cannon launched guided missile (CLGM) and (2)Precision guidance kit for high speed low drag (HSLD). The technologies of the two products are described below: Pinaka battery layout

3August-December 2012

Cannon Launched Guided Missile

Cannon launched guided missile has augmented the firepower capability of India’s main battle tank (MBT). CLGM will be able to engage the enemy tanks up to 5 km.

Cannon launched guided missile

Guidance Block

Guidance block is a DSP-based, computation and communication intensive platform for implementation of guidance and control algorithm. It consists of the flight control unit (FCU), power supply and regulation unit (PSRU), inertial measurement unit (IMU) and thermal batteries.

Control actuation block

CLGM Avionics

CLGM electronics has four sub-systems─a control actuation block, a guidance block, a gimbal laser seeker, and warhead control unit.

Control Actuation Block

This is the rear most sub-system of the missile, responsible for control actuation mechanism. The fully digital fin actuation electronics has been realised on a single actuation control card.

Flight control unit

Warhead Control Unit

Warhead control unit is responsible to keep warhead of CLGM safe during storage, transportation handling and initial phase of launch and for detonating the warhead at right time and right place when target is sensed. The kill mechanism with CLGM is tandem HEAT warhead.


PG Kit for HSLD Bomb

The aim of PG kit is to convert dumb bomb in to a precision strike weapon which increases range of weapon manifold by aerodynamics manoeuvering. The kit is in the form of tail cone and nose cone and can be fitted easily around the bomb body. The tail cone houses mainly electromechanical fin actuation system, INS-GPS module, and a guidance on-board computer.

The nose cone comprises of laser seeker module along with electronics.

Flight Control and Interface Electronics Unit

The purpose of flight control and interface electronics unit (FCIEU) is to implement guidance, navigation and control algorithms, interface with aircraft and GPS/INS unit, and issue control surface deflection commands to ACEU. It is required for real-time computing and sufficient I/O capabilities. FCIEU integrates with navigation sensors and implements three-loop autopilots and the trajectory control guidance algorithm. It implements the algorithms, which are computationally intensive and will have constraints of three-loop response time of few millisecond. Unit is also responsible for communicating with all sub-systems with pre-defined protocols on different serial interfaces. It has power source and regulation unit which generates different voltages required by different components on FCIEU and GPS/INS integrated module.

Salient Features

Interfaces with USB memory for reading mission u

data

Interfaces with aircraft over data bus for mission u

data reading and INS initialisation/ alignment

Senses the release of the bomb from the aircraft and u

after pre-defined delay initiates the thermal battery

Sends control signal to RF switch for correct GPS u

antenna selection

Interface with GPS/INS unit for control and u

navigation

Implements guidance and control laws (roll and u

lateral autopilots)

Interfaces with ACEU for tail fin control u

Transfers laser code to homing head u

Warhead control unit

Nose

Smart tail unit


Sends start of scan command to homing head u

Interfaces with homing head for getting line-of- u

sight (LOS) rate

Senses impact event/proximity and issue warhead u

initiation command

Actuator Control Electronics Unit

DRDO has developed actuator control electronics unit (ACEU) to steer bomb during its flight to the target as it is required to continuously deflect its control surfaces. Functionally ACEU starts operation only after the bomb has been released from the aircraft. The autopilot computes the required fin deflections as per the latex demands. ACEU implements the commanded deflections and deflects the control surfaces of the bomb. In present application, each control surface is actuated by brushless DC motor integrated with incremental position encoder for position/velocity feedback.

Salient FeaturesFPGA-based digital implementation u

Trapezoidal velocity profile implementation for u

position command generation

PID-based controller for motor actuation u

Controls four BLDC motors which drive the fins u

Provision of RS 422 data interface to FCIEU. u

Provision of monitoring voltages and data u

Gimbal Control Electronics Unit

Gimbal control electronics unit (GCEU) is placed in the fore part of semi active guided bomb and performs the basic functions such as searching, acquiring, and tracking a target regardless of the body motion of missile. For this reason, the seeker is mechanically designed as a gimbaled platform to point toward a designated target as well as to stabilise the line of sight (LoS) rate in the inertial space. The measurement of the angular rate of the gimbaled platform is performed by gyroscope and its output is used as a feedback signal in the stabilisation loop. The stabilisation loop of seeker not only precisely follows the rate command generated from the tracking error but also isolates the gimbaled platform from the body motion due to the missile manoeuvering and vibration during flight.

Salient Features On power on, it holds the gimbal pay load u

Communicates over serial interface with FCIEU for u

receiving command/data (e.g. laser code, start of scan, etc.) and sends the telemetry data (sight line rates and other design parameters)

Controls two-axis gimbal driven by LAT, using u

potentiometer feedback.

Actuator control electronic unit Gimbal control electronic unit


High speed sampling of LSD O/P from four quadrants u

and do identifies target (laser code matching).

Performs complete process of target search, u

identification and tracking and sends sight line rate to FCIEU for PN guidance.

Mid-course Guidance Unit

To achieve stand-off distance and accuracy, PG kit is designed with two-level, the mid-course phase and terminal phase, of guidance. Mid-course phase is achieved by integrated GPS-INS navigation unit, whereas in terminal phase, laser seeker is used. The role of mid-course navigation sensors is to navigate the bomb to terminal basket. It provides navigation solutions (position, velocity and attitudes) of the weapon.

Strap-down GPS-INS module consists of the following sections:

Inertial measurement unit (IMU): Orthogonally mounted accelerometers and gyros on 3-axis giving specific forces and body rates.

GPS receiver: Provides absolute position information of the body.

Navigation processor card: Provides fused navigation solution using both sensors data, i.e., IMU and GPS on RS422 interface.

Pressure Casting Technology for Case Bonded Rocket Motors

Propellant grains with higher viscosity resulting from high solid loading or high burning rate and grains with complex grain geometry cannot be processed by conventional vacuum casting technology. To overcome these limitations, DRDO has developed pressure casting technology. Pressure casting can process: Propellant with very high solid loading and in turn high density and higher performance index; high burning rate propellant compositions owing to high viscosity; propellant with low plasticiser content resulting in improved interface properties for better shelf-life; and grains with complicated port geometry

Pressure casting set-up for UWB motor

Pressure casting set-up for LTB motor Mid-course guidance unit


and multiple grain casting (higher production rate).

Pressure casting has been developed using mixer supercharger consisting of a sigma mixer extruder. Propellant slurry after mixing is discharged into mixer supercharger using hydraulic discharge system. Propellant slurry is initially dearated and then pumped into the rocket motor from bottom. After achieving required pressure in the motor case, a specially designed cut-off device is used to seal the motor. It is subjected to curing under pressure in which pressure further increases depending upon coefficient of thermal expansion of propellant slurry.

Pressure casting technology is being used for processing of UWB (Mk-II) and multiple casting of low thrust booster (LTB) motors for advanced naval system programme.

LTB motors have been successfully flight tested in recent pop-up trials with excellent propellant performance meeting the project requirements. The technology has been established for case bonded motor. Pressure casting technology will be a stepping stone to develop technology for casting small caliber motors in large numbers.

Modular Charge System of 130 mm Field Gun and 105 mm Indian Field Gun

DRDO has designed and developed modular combustible cases (MCC) propellant for higher and lower zones, igniter bag, flash reducing discs, additive liner, lead-tin foil, polyester film, and brass stub for modular charge systems. Modules and their components have been joined without use of any adhesive, through a push-fit mechanism so that they can be easily separated for re-use. Dynamic trials have been conducted and pressure, muzzle velocity and ranges have been found to be in agreement with those of service ammunitions.

Design and development of MCS covering entire range of 130 and 105 mm field guns have been

accomplished for the first time in the world. MCS enables several operations with economical and environmental advantages over the cloth bagged charges. Chief among these are the adaptability to automation, higher rate of firing, less training period,

Modular charge system 105 mm Indian field gun

Modular charge system 105 mm Indian field gun

Modular charge system for 130 mm field gun


threats like tandem shaped charge warheads and high penetrating kinetic energy projectiles.

Fuel-Air-Explosive Technology

Fuel-air-explosives (FAEs) are the fuel aerosols formed in air by dispersion of certain hydrocarbons and hydrocarbon oxides, viz., hexane, heptane, ethylene oxide, propylene oxide, etc. These aerosols are detonable over wide range of fuel concentrations in air and yield very high impulse blast compared to that of conventional explosives of same weight and are highly effective against soft targets like A/T and anti personnel (A/P) mines, B vehicles, aircraft, ships, trenches, radar installations, communication systems, troop concentrations, etc. FAEs have the advantage of covering large area, are weight efficient and have no

ERA Mk-I panel–Steel box

Explosive cassette–MetallicERA Mk-I mounted on Tank T-72

Fuel aerosol

less complexity in the charge system, reduced barrel wear, eco-friendly nature and better logistics. The expertise gained will be useful in developing MCS for artillery guns.

India is the only country in the world, which has developed MCS for 130 mm field guns.

Explosive Reactive Armour

Explosive reactive armour (ERA) is an add-on protection for tanks from various threats like shaped charge warheads and kinetic energy projectiles. ERA panel contains one or more ERA elements, which comprise explosive layers sandwiched between metal plates. DRDO has developed ERA Mk-I being used Tank T-72 (CI Ajeya).

ERA Mk-I has the capability of considerably reducing the penetration of MILAN class of warheads. In addition, it is highly effective against other anti-tank (A/T) ammunitions like 125 mm high explosive anti-tank (HEAT), 105 mm APDS, 105 mm high explosive squash head (HESH), etc. It is immune to detonation against small arms ammunition of up to 30 mm caliber. Adjacent ERA panels do not undergo sympathetic detonation when one ERA panel functions due to impact of A/T projectile. The design also facilitates replacement of functioned ERA panel with a new one in a short time. Since the explosive used in ERA Mk-I is waterproof, it retains its efficiency even after deep fording by tank. The additional weight due to fitment of ERA panels on a T-72 tank is 1.5 ton. The fitment of ERA panels on the tank does not adversely affects mobility, manoeuverability, rate of turret traverse, gun control systems, etc.

DRDO is further developing an advanced explosive reactive armour (AERA) for protection against modern


Aerosol detonation

inhibition by land contour and protective structures. DRDO has developed FAE technology for development of various warheads with varying fuel quantity.

Thermobaric Explosive Technology

Thermobaric (TB) weapons are reported to be effective against soft targets in enclosed spaces like tunnel, bunker, field fortifications, underground structures, buildings, machine gun posts, etc. TB weapons are developed using advanced and refined fuel air explosive techniques to create sustained temperature and overpressure on detonation. DRDO has carried out a feasibility study for preparation and evaluation of solid- and liquid-based TB explosive compositions. Compositions produce enhanced blast and thermal effects. DRDO is currently engaged in developing TB explosives for application in warheads for tanks and guided missiles.

Mine Breaching Equipment

Mine breaching can be carried out by both, the mechanical means and the explosive means. In mechanical means, equipment like frails, rollers and ploughs are attached in front of a tank or heavy vehicle. In this case, the mine gets actuated by the load experienced due to passage of equipment. In the explosive means, the blast generated by the explosive is used to actuate mines. This can be accomplished either by use of solid explosives or FAEs. FAEs being in aerosol form cover larger area.

Charge Line Mine Clearing (Vehicle) Equipment

Charge line mine clearing (CLMC) equipment is similar in some aspects to Giant Viper of British origin. It uses explosive blast for breaching pressure susceptible A/T and A/P mines to create a safe lane for vehicles. CLMC comprises the following sub-systems:

Explosive line charge: a high explosive filled rubber lined polyester hose of few hundred meters.

Propulsion unit: a cluster of six rocket motors to achieve the desired range of explosive line charge.

Towing strop: a Flexible steel wire rope used as a link between the explosive line charge and the propulsion unit.

Initiator assembly: an explosive and detonator assembly for initiation of explosive line charge.

Parachute arresting gear: Three parachutes attached at the rear end of hose for straightening the line charge and functioning of initiator assembly.

TB explosive detonation Charge line mine clearing (vehicle)


Trailer cum launcher: an explosive line charge carrier and launcher. The explosive line charger consists number of segments of explosive filled rubber lived polyester hose joined together. The trailer-cum-launcher is two wheeled six ton capacity equipment with cross-country mobility. Elevation of launcher is adjustable.

Fire control unit: for firing pulse generator for propulsion unit

The trailer-cum-launcher is attached to a tank or B-vehicle and towed near to the mine field. The explosive line charge is projected on to the mine field with the help of propulsion unit from a safe stand-off distance. The explosive line charge is straightened in flight by parachutes. After landing, the line charge gets initiated by the initiator at a pre-set delay. The blast generated by the line charge neutralises pressure susceptible A/T and A/P mines and creates a vehicle safe lane. CLMC (vehicle) has been accepted by the users for induction into the Services.

Rocket Assisted Mine Breaching System

Generally, A/P mines are scattered in mine field using remotely delivered vehicles. Such mine fields pose great threat to mobility of an infantry soldier. Specialised vehicles are required to breach a path through the minefields which is time consuming. DRDO has developed a lightweight A/P mine breaching system, which can be carried by a single soldier. The system makes use of detonating cord for creating safe lane for infantry. It consists of the following sub-systems: High explosive filled detonating cord; small rocket for projecting detonating cord to achieve the desired range; firing pulse generator for mini rocket and detonating cord; and carrier for detonating cord and rocket launching system.

NBC Contamination Set Marker

DRDO has developed contamination set marker (day and night) for demarcating the nuclear, chemical and biologically contaminated zones in battlefield. The marker can be mounted on A and B type of vehicles and is capable of placing the markers in the ground with the help of explosive force while the vehicle is in motion. It comprises a platform with 24 markers. Each marker has a flag of specific colour to denote the type of risk. It is driven into the ground by an electro-explosive device. The marker consists of the following sub-systems: Marker with each unit having cotton fabric coloured flag on the top and spike at bottom for easy penetration in the ground; pyrocartridge for generating gas pressure to impart necessary velocity to marker; rectangular platform of 24 holes for accommodating markers in

Rocket assisted mine breaching system

Markers mounted on 3 ton Shaktiman Pegged markers


accommodates ethylene oxide as fuel. Central burster charge is used for dispersion of fuel to form fuel air explosive cloud.

Grenade housing unit: It consists of four HE filled grenades each fitted with electrical delay detonator. The functioning of the grenades after the preset delay initiates the fuel air explosive cloud.

Fuel Air Explosive Mine Clearing SystemThe fuel air explosive mine clearing system is

projected by a rocket on to the mine field using tubular launcher from a safe stand-off to create safe lane for vehicles. It consists of the following sub-systems: Extendable probe for required stand-off to warhead; switching unit acting as impact fuze; fuel canister with central burster charge. It carries fuel for aerosol formation; grenade ejection unit consisting of ejectable HE filled grenades for detonation of aerosol; rocket motor for achieving desired range; retarding tail unit with parachute achieving desired terminal parameters; and an electronic delay unit for providing electrical pulse as per sequence of operation.

The extendable probe of FAE mine clearing system gets the switching unit armed on impact on ground. This energises the explosive train leading to the formation of aerosol and subsequent detonation. The blast generated by the system clears pressure susceptible anti-tank mines in the circular area around the impact point.

vertical position; and firing control unit for supplying electric pulse to pyrocartridge. The pulse produces gas pressure, on the piston of the marker that drives the marker into the ground. The marker then stands erect with the flag fully open. The system has been inducted into the services.

Picket Driving System for Armoured Engineering Recee Vehicle

The equipment consists of 40 pickets/markers mounted on an armoured engineering recce vehicle. It is a robust system, which can withstand cross-country movement of the vehicle. The functioning of system is same as contamination set marker (day and night).

AERV with picket driving system

Fuel Air Explosive Systems/WarheadFuel Air Explosive Warhead for Breaching of Tank Turning Pad

It is a portable system having a single fuel air explosive warhead for clearing tank turning pad. It consists of a fuel canister with central burster charge having ethylene oxide and grenade housing unit filled with solid HE. The warhead performance was evaluated against dummy A/T NDMK-I mines. It consists of the following sub-systems:

Pad canister with central burster charge: The canister FAE mine clearing system


Bund Blasting Device

When mechanised army marches forward, it encounters various types of obstacles such as canal banks and ditch-cum-bunds (DCBs). To launch equipment, bridges and to enhance the mobility of mechanised infantry in the war field, it is essential to reduce the height of canal banks and DCBs. DRDO has designed and developed bund blasting device based on the principle of hollow charge and a rocket assisted high explosive filled follow through projectile (bursting charge). On activation, main bursting charge moves down with the help of a rocket motor, which on the way activates a specially designed hollow charge initiation device. Hollow charge creates a pilot hole in the ground. Main bursting charge enters to the base of the pilot hole, detonates after a pre-set delay of 3 s and creates the required breach/crater.

Salient Features Man portable u

Gross weight (single BBD): 21 kg u

No power back-up is required for operation u

Time taken for deployment: 15-20 min u

Multi-mode Hand Grenade

Grenades of natural fragmentation type are being used by the infantry world over since a long time. Indian Army still uses the 36 M—a grenade which also has severe reliability problems due to its unreliable fusing system and uneven fragmenting pattern making. It

is unsafe even to the thrower. DRDO has developed a multimode lightweight modular hand grenade to overcome these defects. It uses preformed cylindrical mild steel fragments to achieve uniform distribution. The grenade is available in defensive (gross weight 490 g) and offensive mode (gross weight 260 g).

Salient FeaturesMulti-mode concept u

Offensive and defensive grenade. Lethal radius of u

3-5 meters from point of burst in offensive mode. In defensive mode it incapacitates human being within the radius of 8-10 meters from the point of burst but safe beyond 20 m

Uniform fragmentation pattern u

Higher splinter density: More number of fragments u

embedded in plastic matrix to provide higher splinter density of fragments

Maintenance free and highly reliable u

Operational temperature range of –20 ºC to 55 ºC. u

Storage temperature range of -50 ºC to 75 ºC u

Bund blasting deviceMulti-mode grenade: Section view (top)


The grenade has GS approval for induction into the Services. Bulk production order of 10 lakh grenades has been placed by the Army on Ordnance Factory Board.

Warhead and Exploder for Advanced and Light Torpedo

DRDO has d e v e l o p e d warheads and exploders for t o r p e d o e s advanced and light (TAL) for use against submarines. The main function of exploder is to detonate warhead and provide safety during various courses of actions. An electro-mechanical type of exploder, which initiates detonation on impact to the target, has been designed and developed for the warhead of TAL. The exploder has all in-built safeties required for storage, transportation, handling and operation. An interruption barrier in the form of 12 mm aluminum plate between detonators and the receptor charge has been provided which prevents detonation of warhead in case of accidental firing of detonators in disarm condition. The exploder can be used with the warhead of torpedo meant to be launched both from helicopter and ship.

Non-Lethal Ammunition

DRDO has designed and developed riot control ammunitions for police and paramilitary force. The following types of ammunitions have been developed:

Plastic Bullets

Non-metallic, non- u

poisonous, and non expanding after penetration

Induces similar sound u

effect as that of ball ammunition up to 150 m Causes only superficial u

injuries at 60 m and above range

Available in two calibers, u

i.e., 303" and 7.62 mm

Can be used by in-service u

weapons without any modification

Frangible Ceramic/Me-tallic Ammunition

Non-toxic and eco- u

friendly. Available in 9 mm caliber Can be fired from u

standard service weapons without any modificationDisintegrates into u

powder on hitting hard targets like walls, metallic plate, etc.The ammunition is u

being used by the state police, paramilitary and India Army. Six lakh bullets have been supplied to these forces.

Indigenously Multi-Channel Time Interval Counter

DRDO has designed and developed a multi-channel time interval measuring equipment for test evaluation of armament stores and detonic studies. The information corresponding to 10 different time intervals is sensed and stored in its memory and can be recalled individually, and displayed on a common digital readout. The equipment has been provided with

Assembled exploder


multi sensing facility to either activate all the channels independently or simultaneously depending upon the field trial requirements. It is used for measurement of velocity of a projectile, fragments, and shock/detonation wave velocity.

Salient FeaturesTen channels u

Single four digit display for data and two digit u

display for channel indication in four different time ranges

Can measure time intervals from 1 µs to 9.999s with u

an accuracy of ±1µs

Ready, over flow indications u

Exploding Bridge Wire Detonator

DRDO has developed highly reliable, accurate and safe exploding bridge wire detonator (EBW). EBW is a secondary explosive-based initiating device for simultaneous initiation of very large surface areas. It consists of a very small gold wire placed in direct contact with the explosive, which when exploded through electric discharge from a capacitor comes to plasma form and initiates the explosive next to it by shock, heat, ionisation or a combination of all. When a number of EBW detonators are fired together, the simultaneity comes to tens of nanoseconds.

These detonators are designed for the systems where high reliability, safety in handling and simultaneous initiation of number of events is the prime requirement. The detonators are especially used for precision timing and firing for in-flight functions such as rocket motor ignition, warhead detonation, missile stage separation, and precision initiation of the explosives.

Salient FeaturesSafe to handle; contains only secondary explosive u

and require comparatively higher power and current for initiation as compared to conventional detonators

Highly reliable under all environmental conditions u

and cannot be detonated by stray or induced current

Baffle Range

Baffle range uses an improvised concept of a system of ground barriers, side walls, baffle walls and stop butt to arrest the misdirected bullets. The land required for the baffle range can be reduced to 15-20 acres instead of 500 acres required for the conventional range. DRDO has designed baffle ranges for small arms firing. This has reduced the area required as compared to conventional range. Consultancy for construction of such ranges is being provided to various units of the army/Paramilitary forces.

Salient FeaturesAccommodates six firers in lying, kneeling and u

standing-in-trench firing positions from firing points at 500, 400, 300, 200, 100 and 50 m (standing position only)

Safe against firing error of 14º in the horizontal plane u

and 12º in the vertical plane from the intended line of fire

Weapons authorised on the baffle range include 9 u

mm carbine and pistol; 5.56 mm INSAS; 7.62 gun machine MAG58; 7.62 mm sub-caliber for 106 RCL;

Bridge wire detonator

Baffle range


9 mm sub-caliber for 84 mm RCL; 7.62 mm SLR, and Ak-47

Shaped Charges and Explosively Formed Penetrator

To keep pace with the advancements in the field of shaped charge warheads against MBT’s, modern ships, submarine, etc., advanced state-of-the-art shaped charge warhead designs have been evolved and tested by DRDO. These warheads are suitable for use in different weapon systems like anti-ship, anti-missile and anti-submarine systems, besides sea mines, A/T guided missiles and hard kill based active protection system. DRDO has facilities available for:

A/T off route mine system with EFP warhead u

Development of EFP warheads for anti-missile role u

Multi P-charge-based warhead with two layers to u

kill soft targets in large area for anti-ship role

Shaped charge-based warhead for defeating double u

hull submarine

Heptafluoropropane Technology

Heptafluoropropane is internationally approved as Halon 1301 substitute for new generation fire protection systems for both civil and military applications. This agent is highly effective, non-corrosive, electrically non-conductive, non ODS, less toxic and leaves no residue on applications. It is ideally suited for fire suppression applications and is acceptable for use as a total flooding fire extinguishant for the protection

of occupied space as per NFPA 2001. The production of HFP will lead to self-reliance at much lower cost than the imported. More than 80 per cent of the fire protection uses are with the civil sector industries such as oil, power, telecommunication industries, etc. Process demonstration of the technology has been completed at pilot scale (55-65 g/h) and technology transferred to M/s Gujarat Fluorochemicals Ltd under DRDO-FICCI-ATAC programme. Total value of ToT is Rs 8.75 crores.

Salient FeaturesContinuous process u

99.9 per cent purity without side products u

Boiling point : -16.4 u oC

Minimum extinguishing concentration: 6.6 per cent u

(v/v)

Zero Ozone depletion potential u

Global warming potential : 3300 u

Atmospheric lifetime : 31-42 years u

No observable adverse effect level : 9.0 per cent u

(v/v)

Lightweight Fire Approach and Proximity Suits

DRDO has designed lightweight fire protective approach and proximity suit ensembles to shield wearer from extremely hot ambient temperature to enable wearer combat fire. The complete ensemble comprises a coat, pant, hood, pair of hand gloves and a pair of shoes. With the complete ensemble of approach suit donned, a fireman can work at a distance of 5 m from an aviation oil fire having flames of temperature 1120 oC for a period of 10 min while wearing the proximity suit a fireman can work at a distance of 3 m from the same for the period of 4 min 15 s.

The complete ensemble is relatively thin and lightweight for relatively high resistant to liquid water absorption. The coat, pant or overall includes an outer


shells; a moisture barrier positioned within the outer shell and a face cloth positioned within the moisture barrier. In fire proximity suit, a layer of thermal barrier is added between innermost layer and moisture barrier layer. Materials used for various fabric layers are specific blends of basofil, carbon fibres, nomex fibres, fire retardant viscose fibres and fire retardant cotton fabric.

In lightweight fire approach and proximity suit, weight has been reduced by 23 per cent to 24 per cent in totality over the existing already developed aluminised suit. The weight of both the suit is 6.4 kg and 7.2 kg approx, respectively. These suits provide protection from conductive, convective and radiant heat and can be used in fire fighting application in Army, Air Force and Navy in addition to civil fire services, oil rig platforms and oil depot, ONGC and steel, glass, plastic and chemical industries.

With the complete ensemble of approach suit donned by a fireman, it has been tested from a distance of 5 m from an aviation oil fire having flames of temperature 1120 0C for a period of 10 minutes where fireman was in comfort level while that of proximity suit is 3 m for the period of 4 min15 s.

Portable Fire Extinguisher

DRDO has developed a portable Fire extinguisher with capacity to hold 9 l water air stored pressure. The extinguisher requires minimal maintenance, easy to charge, easy to carry and operate, has long service life of over 20 years, highly reliable, does not requires painting, can be used with additives, and totally safe to operate. The maximum throw of the extinguisher is 7 m with a total discharge period of one minute. It is used as first aid fire fighting equipment in Army, Air Force and Navy to combat class ‘A’ fires. It can also be used in steel, glass, plastic and chemical industries.

Salient Features Body material : Stainless Sheet u

Cylinder diameter : 175 mm u

Charging pressure : 7 kgf/cm2 u

Total weight : 13-14 kg u

Discharge hose length : 0.6 m u

Emergency Escape Chute

DRDO has developed an emergency escape chute is used for evacuating who get trapped in high rise building oil rig platform during fire hazard. The emergency escape chute is a tubular fishnet made of strong fire resistant Kevlar fibre which is kept extended by incorporation of aluminium alloy rings in the net at an interval of one meter. Kevlar zero twist yarn has been used for knitting purposes using


specially designed knitting needles. The tubular design with zigzag sliding net is inside with no possibility of any openings even if there is a cut by any means. The chute is simple and safe to use and requires no training or practice. It can be made up to 50 m length, also bear load up to 5 tons and used in conjunction with auto inflatable raft. The chute can be modified as per requirement. The chute can be used for rescue operations where it can be attached to a helicopter or aircraft. It can also be used for climbing from ground to the helicopter or vice versa.

Water Mist-based Fire Suppression System

The water mist technology, developed indigenously, is at par with the internationally quality. It provides an effective and environmentally benign alternate solution to Halon-based fire protection systems which are to be phased out completely by 2012 due to their adverse effect on environment. This technology can also be applied effectively for cooling applications. Low pressure twin fluid water mist system having atomiser for mist generation in the droplet size range

of 10-100 µm (volume mean droplet size ~50 µm) has been developed for compartment total flooding fire protection application. Minimum fire extinguishing concentration of water mist and volume-based scaling law for mist system design for total flooding fire suppression has been established.

Validation of water mist-based fire suppression system (WMFSS) for submarine applications by real scale fire suppression experiments in a submarine fire simulation compartment of size 590 m3 has been carried out as per international standard IMO CIRC 1165. The technology has been accepted for induction in Navy.

Portable, Hand-held and Backpack Low Pressure Water Mist Gun System

DRDO has indigenously designed and developed portable, hand-held and backpack low pressure twin fluid water mist gun system. The system is useful as a first-aid fire fighting for class A, B and electrical fires in naval platforms like ships, submarines, POL stations, defence stores, trains, process industries, civilian buildings, hotels, warehouses, farm stockyards, etc. The system successfully passed fire tests as per international standard EN 3:7-2004 for B233, A55 and live electrical fires.

Salient Features

Water mist is environment friendly; Zero ODP and u

GWP

Submarine fire simulation facility Portable backpack low pressure water mist gun system


Low water requirement; u

Easy to operate and reusable u

Low refilling and recharging cost u

The system has been validated as per EN-3:7-2004. Patent (application no. 694/DEL/2011) has been filed for the system and technology has been transferred to M/s ASKA Equipment Ltd, Delhi.

Instant Fire Detection and Suppression System for BMP-2/2K

Instant fire detection and suppression system (IFDSS) is a micro controller- based fire detection and suppression system for armoured fighting vehicles/tanks. The system detects the fire and suppresses it either automatically or by pressing manual override switch in crew as well as in engine compartment of the tank. The detector unit has IR sensors and detects the fire in crew compartment and sends the confirmation signal of fire to main control unit (MCU) over control area network protocol. MCU takes the necessary action to activate the fire extinguishers. A fire-wire is a flexible heat detecting wire, having one or more elements joined in series by means of various connector accessories. It is a linear thermal detector, which is directly interfaced with the MCU. Its logic is designed for over heat, fire, and open circuit and short circuit conditions. The system has the feature of continuous health monitoring of detector units, alarm and flasher

unit, fire wire and fire extinguishers. The system also has features like built-in-test-equipment (BITE) and audio-visual indication of over heat and fire conditions in the engine compartment.

Salient FeaturesSaves crew and vehicle both u

Micro controller-based operation u

Free from false triggering u

Combat and peace mode operation u

Detection of fire with in 20 ms u

Discriminates between true fire signature and non u

fire stimuli

Logging of important fire events for post fire u

analysis

Complete fire out below 150 ms u

The system has been accepted for introduction into the Service and an order of Rs 167.87 crores for 2551 sets of IFDSS for ICVs BMP-2&2K has been released by Ministry of Defence.

Fire Control Unit for AN-32 Aircraft

Fire protection system developed by DRDO for AN-32 aircraft consists of microcontroller-based BI-2A control unit and thermocouple-based fire detectors which prevent false firings and discharge of fire extinguishers. The system operates in automatic and manual mode. The system is designed to protect left wing, left engine nacelle, right wing and right engine nacelle.

Salient FeaturesLED indicators for fire and thermocouple u

connectivity

Highly immune to false fire alarm u

Solid-state relays used in place of electromechanical u

relays to make system more reliable and fast

Thermocouples connectivity with the system u

through differential mode amplifierInstant fire detection and suppression system for BMP 2 and 2K


Amplification of signal from thermocouples: 10 u

times (to reduce noise and makes the system more accurate)

Fire detection and processing time : < 25 ms u

Two parallel control cards for redundancy u

Hardware and software filtering to reduce noise u

EMI/EMC testing as per MIL Standard 461C u

Environment testing as per MIL Standard 810F u

Product successfully demonstrated and accepted u

by the Air Force.

Efficient Fire Suppressing Gel

Water is always the choice for extinguishing fire because of its natural profuse abundance, but most of it (~ 90 per cent) goes waste as run-off during fire extinguisation. To avoid the wastage of water, a fire suppressing gel (FSG), with water absorption capacity of 300 g water/g of gel, has been developed. When gel containing water (~0.5 per cent) is used to extinguish the fire, it sticks to the burning object and provides water for heat absorption from fire. It minimises both time to extinguish the fire and the quantity of water used. It is useful in preventing, retarding, suppressing and extinguishing the fire effectively, in less time. On application, it brings effective cooling and the articles fall below their combustion temperature. FSG forms a

gas-impermeable barrier on the surface of combustible objects, which reduces the supply of oxygen to the surface of combustible objects. The gel has a shelf-life of more than five years.

Multipurpose Fire Extinguishing Powder

DRDO has successfully developed a multipurpose dry chemical ABC powder for extinguishing all types of fire. It has excellent fire extinguishing properties, high fluidity, high humidity resistance, high electrical insulation, non-toxic, non-corrosive, eco-friendly and long shelf-life. CFEES-KV-GREEN powder is suitable for use in all types of portable fire extinguishers, mobile extinguishers and fixed installations. Both nitrogen and carbon dioxide can be used promisingly as dry propelling agents. It confirms to ISO-7202 and IS-14609 standards.

The technology has been transferred to the production capacity of 25 ton/month. Patent (application no. 607/DEL/2011) has been filed for the powder.

Salient Features

Suitable for use in all types of portable fire u

extinguishers, mobile extinguishers and fixed installations

Both nitrogen and carbon dioxide can be used u

Fire control unit for AN-32 aircraft Fire suppressing gel


promisingly as dry propelling agents

Halon alternative u

High fluidity u

High humidity resistance u

High electrical insulation u

Eco-friendly and long shelf-life u

Applicable for all classes of fire and can sustain u

extreme temperature variations

Laced Reinforced Concrete Explosive Storage Building

The concept of laced reinforced concrete (LRC) Igloo type blast resistant storage magazine is the latest in order to have reduced safety distances and compact layout thereby ensuring optimum utilisation of land while ensuring safety and serviceability of explosives in case of an accidental explosion in adjacent Igloo. Igloo is an above ground earth covered magazine with a more uniform stress distribution when exposed to blast loads and prevents sympathetic detonation. LRC Box Type Igloos is a combination of two innovative concepts—box type construction, and use of bent shear lacing in addition to the conventional reinforcement. As compared to conventional RCC, LRC technique is

very useful for blast resistant structures subjected to close-in detonations.

Salient FeaturesLRC structural elements exhibit large ductility/ u

energy absorption and excellent concrete confinement.

Ductility of flexural reinforcement is fully u

developed

Integrity of core concrete is maintained despite u

massive cracking

Buckling of compression reinforcement is u

restrained

High shear stresses at supports and local shear u

failures are prevented

Post failure fragments are reduced in terms of u

quantity and velocity

40-50 per cent reduction in steel as compared to u

RCC.

Design, up to 136 ton (NEC), has been approved by STEC and more than 250 Igloos of various capacities have been given to Ministry of Defence. The storage inside quantity distance (SIQD) has been reduced from 2.5 scaled distances to 0.5 scaled distances. The process inside quantity distances (PIQD) have been reduced from 8.0 scaled distance to 7.2 (front), 6.8 (side) and 6.0 (rear) scaled distance. The outside quantity distances (OQD) have been reduced from 22.2 scaled distance to 19.0 (front), 18.0 (side) and 16.0 (rear) scaled distance.

Multipurpose fire extinguishing powder

An igloo building


Hazard Classification of Military Explosives

Assignment of military explosives into various hazard divisions and compatibility groups is required in order to control the operational conditions with reasonable regard to safety of life and property. The hazard classification trials were conducted as per UN Test Series 6 of UN Manual Tests and Criteria for the Classification of Explosive Substances and Articles.

Propellant with Energetic Ingredients

Based on the experience gained from the nitramines-based propellant composition, a new propellant composition has been developed to further enhance the Isp with energetic ingredients consisting of active binders and high level of nitramines. Processing technology for active binder preparation, which includes uniform mixing, solvent removal and collection process, has also been established.

Wooden package for SPA–II propellant

Fire ball

High Solid Loading Propellants

Conventional HTPB/AP/AI-based composite propellants are in use for various strategic and tactical missiles. By increasing a few seconds of Isp, range of a missile can be enhanced without major change in other sub-systems of the missile. As per thermodynamics of the propellant combustion, Isp depends on flame temperature and mean molecular weight of gaseous products after combustion which in turn depends on heat of formation of propellant ingredients. Therefore on incorporation of ingredients with positive ΔHf in propellant composition, Isp enhances significantly. But incorporating these ingredients affects the safety parameters, burning rate, and mechanical properties. While developing such compositions these factors must be considered for safe processing and realisation of flaw less propellant grains.

DRDO has developed a new HTPB/AP/AI propellant composition with 10 per cent nitramines (RDX, HMX and CL-20) along with safe methodology of processing like incorporation of suitable plasticiser and mixing cycle.

Static test of 2 kg BEM with propellant

Woven basket type MTV-based Igniter for Solid Rocket Motors

The reliability and performance of solid rocket motors depends on igniter and its composition. An inadequate design of igniter and improper selection of igniter composition cause undesirable ignition of solid rocket motors leading to mission failure. DRDO has developed a magnesium/teflon/viton (MTV)-based igniter using woven basket type igniter canister of composite material manufactured using indigenous technology. MTV compositions also have excellent environmental and thermal stability and good chemical compatibility with most ingredients used for the pyrotechnic formulations.

The basket type canister allows higher mass discharge of combustion products and MTV compositions provide

MTV-based ignitor


of eight reagents, a test plate, an instruction manual, and a colour chart.

Salient FeaturesDetects and identifies a wide range of military u

explosives in laboratory and field conditions in pre- and post-blast scenario Probability of false alarms is minimum u

Entire testing process is carried out at ambient u

temperature Results obtained in 2 to 3 min u

Sensitive up to ppm level u

The kit is cost-effective u

Three variants—Drop EDK for detection of bulk explosives in general, Spray EDK for detection of explosive at site by spraying reagents, and disposable pocket EDK, which contains small sized reagent bottles, have been developed. The kits are being used by the army, bomb detection and disposal squads, and paramilitary forces.EDK is easy to use. A drop of reagent is put on the sample and the colour formed is compared with a colour chart provided with the kit thereby identifying the explosive.

DRDO has given non exclusive licence to M/s Vantage Integrated Security Solutions Pvt. Ltd, Noida, for manufacture and sell/supply EDK in India. DRDO has signed A MoU has also been signed with M/s Crowe & Company, USA, for exclusive rights of manufacturing and sale of EDK exclusively in US.

84 mm Incendiary Ammunition

DRDO has developed solid incendiary composition comprising of zirconium metal powder and red phosphorus bound in crepe rubber matrix that produces high temperature and suffocating smoke effects. 84 mm incendiary ammunition filled with this composition has also been developed for firing from the shoulder fired weapons. On functioning, a small quantity of high explosive disperses burning fragments that burn for about 3 min in the target. The high

soft ignition due to low gaseous products and high heat output which may be useful in avoiding initial high pressure peak generally observed using other type of pyrotechnic compositions.

COMBO Gas Generator

COMBO gas generator (GG), combination of gas generator and underwater booster, is used in underwater canister launched missile for ejection of missile out of canister and also to provide thrust to carry missile outside the water surface. COMBO GG is multi-perforated, cast in composite sleeve grain with150 kg of composite propellant, first of its kind in India. COMBO GG requires of low-aluminised propellant. DRDO has successfully developed a propellant formulation for realizing COMBO GG. The propellant formulation is based on ultrafine ammonium perchlorate, solid burning rate catalysts and spherical aluminum powder.

DRDO has also developed the necessary casting and handling fixture for processing such complex grain. A pressure curing technology has been adopted for realising better interface properties between propellant and casing. Thermal stress management is done by providing intermediate and end loose flap arrangement. COMBO GG has been successful flight tested in pop-up trial of underwater missile system.

Explosive Detection Kit

DRDO has designed and developed an explosive detection kit (EDK) for detection and identification of explosives/trace explosive residues and improvised explosives. It is a chemical reagent based kit working on the principle of colour chemistry. The EDK consists

COMBO gas generator


temperature of burning fragments ignites combustible materials in contact and simultaneously generates suffocating smoke forcing occupants to abandon their safe shelters. The composition has been optimised for close combat in urban terrain and has potential use in low intensity conflicts.

Salient Features Weight of round : 3.2 kg u

Effective range : 300 m u

Burning duration : ~ 3 min u

Temperature output : ~1400 u oC

Spread diameter : ~ 25 m u

Capability : Can penetrate u

thick brick wall

At present there are no products with similar features available for import. There is 84 mm HEDP 502 round of SAAB International, Sweden, containing 0.6 kg of high explosive as tandem mode shaped charge ammunition that gives penetration and fragmentation effect but does not generates burning fragments that produce high temperature and suffocating smoke.

Through Bulkhead Initiator

Presently, rocket propellants are ignited using electrical-based igniters. These igniters use electrical

84 mm incendiary round (left) and static performance

Schematic diagram of through bulkhead initiator

cables which run through the rocket motor thereby posing a high degree of risk of ignition due to static charges. To prevent any accidental ignition and also to ignite the rocket propellant reliably, an explosive-based device called Through Bulkhead Initiator (TBI) has been developed first time in the country by DRDO. The device has been proven successfully in various static and dynamic trials. TBI does not need any electrical connection for its functioning therefore is not susceptible to static charges. It also provides post-firing sealing to gaseous products rearwards. It can be used for reliable ignition of present and futuristic rocket motors.

IR Flare for Countermeasure Dispensing System

Infra red (IR) guided missiles pose major threat to military aircraft. IR flare is used to seduce an IR seeker away from the target by having a stronger signature than that of the target itself. Pyrotechnic decoy flares are still the most commonly used passive countermeasures to lure away incoming heat seeking missiles. Their broad application can be attributed to ease of loading, highly reliable and cheaper constituents such as metallic fuels and oxidisers.

DRDO has developed the IR flares for countermeasure dispensing. The flare has four major components, viz., IR emitting pellet, impulse cartridge, flare container and safety and functioning unit. Qualification testing of IR flares and impulse cartridge has been completed in association with RCMA (AA), ORDAQA (A), QRDAQA (GW). The development trials have been successfully

completed and demonstrated to users. DRDO has signed a MoU for transfer of technology to BDL, Hyderabad, for the production of countermeasure dispensing system.

Multiple Flare Dispenser

The impulse cartridge is fitted into the flare container. The complete flare is then loaded into a multiple flare dispenser. When the impulse cartridge receives an electrical impulse from the dispenser, it is initiated and produces sufficient gas pressure to eject the payload with safety and functioning unit into the air. Gas pressure is maintained by an effective piston seal arrangement, which ensures a consistent velocity.

The safety and functioning unit reacts to the stimulus of the impulse cartridge gas and flame and prevents initiation of the IR pellet until the payload completely exits the flare container. The IR pellet is rapidly ignited and burns all over its external surface to emit an infrared signature in excess of the aircraft signature.

User’s trials have been carried out in association with Air Force. The flares performed satisfactorily with respect to the safe dispensation, proper ignition and functioning.

Impulse cartridge

Countermeasure dispensing system loaded with flares (top) and flare fired from dispenser

Technology Focus focuses on the technological developments in the Organisation, covering the products, processes and technologies.

Editorial CommitteeChairmanDr KD Nayak, DS&CC R&D (MED, MIST & Cyber Systems) DRDO HQCoordinatorShri SK Jindal, Director, DESIDOC, Metcalfe House, DelhiMembersCmde PK Mishra, Director of Naval Res. & Dev., DRDO Bhavan, New DelhiShri Sudhir K Mishra, Director of Missiles, DRDO Bhavan, New DelhiDr K Muraleedharan, Director of Materials, DRDO Bhavan, New DelhiShri Sudhir Gupta, Director of Aeronautics, DRDO Bhavan, New DelhiSmt Nabanita R Krishnan, Director of DMIST, DRDO Bhavan, New DelhiDr DK Kharat, Director of Armament, DRDO Bhavan, New Delhi

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