October 26, 2021
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Pouncing defence
Role of modern air to ground missiles

The use of advanced air to ground missiles in modern battlefield is becoming quite a familiar approach to block enemy advancement and secure air space access from a stand-off distance by way of launching long range air to ground weapons.

Most militaries are using satellite technologies and GPS, air to ground missiles which can be launched against static targets, moving targets, ships, enemy radar positions as well as air defence systems, while saturating enemy SAMs.

Although there are several ongoing programs to produce a credible A-T-G missile system, militaries are keen to have one type of missile in their arsenal which can perform a series of tasks at the hand without going for a change of operational parameters while conducting high risk missions.

The Joint Air to Ground Missile (JAGM) is a US Army and US Navy program aimed at the development of a single missile to replace AGM-114 Hellfire, BGM-71 TOW and AGM-65 Maverick beginning in 2016.

The new missile can be fired from both fixed- and rotary-wing platforms such as AH-64D Longbow Apache, AH-1Z, MH-60R Seahawk, F/A-18E/F Super Hornet, and Sky Warrior UAV. The JAGM missile will defeat moving and stationary targets at extended ranges in all weather conditions.

Apart from JDAM, the AASM (in French, Modular Air-to-Ground Weapon) is a family of new-generation smart air-to-ground weapons. All the variants of the family can be fired from a standoff distance and can be fire-and-forget.

Depending on each variant, the AASM can strike a fixed or moving target with extremely high precision, both day and night, under all conditions. Interoperable and combat proven, the AASM meets all the spectrum of Air Forces’ needs at the tactical level.

The AASM is made up of guidance and range extension kits that transform a standard bomb body into a smart weapon. Its engine provides it with range greater than 50km, meaning it can be fired at a standoff distance. Autonomous after it has been dropped, it can be used at low altitudes, cross hilly terrain or veer sharply from the firing aircraft.

The AASM’s modularity allows it to be used on 125, 250, 500 and 1000kg bomb bodies and have several guidance kits according to the mission: INS/GPS, INS/GPS/infrared and INS/GPS/laser.

The infrared imager version overcomes target coordinate errors by undertaking a terminal correction just before impact, and the laser version can be used to strike highly mobile targets.

The AASM-250 is operational in the French Air Force in overseas operations and has been successfully used in combat on the Rafale since 2008. The AASM-125 was successfully tested in February 2009 on a Mirage 2000. The AASM-1000 is under development, as are new features such as airburst and data link.

Due to its ease of use, maneuverability and its vertical strike capability, the AASM covers all offensive air missions: in-depth attacks, Air Interdiction, Close Air Support (including in urban environments), SEAD-type or anti-ship special missions, etc.

The AASM is programmed with target coordinates and can be reprogrammed in flight, enabling it to engage several targets simultaneously.

The AASM is also commercialized by MDBA as part of its comprehensive weapons offer, which aims to meet the needs of international air forces. The US is all set to change the existing A-T-G weapons profile.

The most important air-to-ground missile carried by Western fighters is the AGM-65 Maverick. The USAF is planning to deploy the missile on more than 3,000 aircraft.

Maverick was developed by Hughes to meet a USAF requirement for a highly-accurate weapon which could be used for close air support or as a stand-off weapon able to attack high-value targets.

More than 26,000 TV-guided AGM-65A and AGM-65B Maverick rounds were built. During 1,221 firings the average hit rate was 86 per cent. Mean radial error from the centroid of a tank-sized target was only 3ft (lm) during trials with tele­metry-equipped rounds.

The latest USAF version is the AGM-65DIIR (Imaging Infra-Red) version which entered low-rate production in April 1983. Simple IR seekers such as those fitted on Sidewinder and Magic are designed to detect and track ‘hot spots’ such as engine jet pipes or warm airframes.

IIR units are the thermal equivalent of TV, creating a video image which reflects the temperature level of the individual objects or items of terrain in the field of view.

Like a TV image, the IR ‘view’ may be used to guide a PGM, but in this case the weapon may operate by night or in conditions of poor visibility, and is not confused by smoke.

Since the image is thermal rather than optical, the AGM-65D will be a useful anti-radar weapon for the F-4G Wild Weasel anti-radar aircraft.

Radars have in the past avoided attack by anti-radar missiles simply by switching off their transmit­ter. AGM-65D allows the ‘Weasel’ to cope with such countermeasures by launching a round to home in on the residual heat emitted by radar sets.

Russian experience

The versatile Kh-25/AS-10 Karen family of missiles was developed to replace the earlier Kh-23/Kh-66/AS-7 Kerry, itself developed as a counterpart to the US AGM-12 Bullpup series. Like the Bullpup the Kh-23/Kh-66 suffered persistent difficulties with its cumbersome radiofrequency guidance system.

The Kh-25M/AS-10 Karen was designed around the model of interchangeable homing seekers, making it a defacto equivalent to the ubiquitous US Hughes (now Raytheon) AGM-65 Maverick missile.

The missile uses canard controls driven by a common SUR-73 guidance and control module. The PRD-276 solid rocket motor exhaust is via paired nozzles on the aft fuselage, permitting the installation of a tail antenna aperture for datalink equipped variants. The motor has a two phase boost/sustain burn profile.

The Kh-25ML is fitted with a 24N1 series semi-active laser homing seeker. It is used primarily to destroy hardened battlefield targets like fortifications, bunkers, or armour.

Achievable CEP is cited at 4 metres. The F-27 warhead has two components, one in the centre fuselage, and in the otherwise unoccupied tail section aft of the nozzles.

The 24N1 seeker has an IFOV of 2º and a Field of Regard of 30º. A proportional navigation control law is used for terminal homing. Post launch the autopilot is programmed to fly a climbing trajectory to preclude the missile exhaust obscuring the target view from the launch aircraft.

Missile variants

Variants of Soviet era strike aircraft such as the MiG-27 Flogger, SU-17M and SU-22M Fitter carried nose mounted optical target tracking sensors with boresighted laser designators, for targeting weapons such as the Kh-25ML series.

The Kh-25MAE variant employs an inertial navigation system and an unspecified active radar seeker, it is intended for attacks on a wide range of surface targets including vehicles, parked aircraft, helicopters, C3 targets, POL targets and structures, under day, night and adverse weather conditions.

The seeker is an MMWI Ka-band design, the PSM-E developed by Phazotron, and is comparable to the seeker in the US AGM-114L MMW Hellfire variants, but with a narrower antenna scan angle and larger aperture. The manufacturer has published numerous discussion notes extolling the virtues of MMW seekers for this specific application.

The Vympel Kh-29/AS-14 Kedge is a Russian supersonic equivalent to the French AS.30 and US AGM-65 Maverick, and is primarily intended for interdiction and close air support, maritime strike roles, and attacks on hardened concrete shelters and structures.

An APU-58 or AKU-58 launcher is used, on the Su-27/30 Flanker (up to 6 rounds), the MiG-27 Flogger (2 rounds), SU-17/22 Fitter (2 rounds) and SU-24M Fencer (3 round). Multiple variants exist.

The Kh-29L (Izdeliye 63 or AS-14A) is a semi-active laser homing variant used in the manner of the AS.30L, with a 24N1 seeker. The Kh-29T (Izdeliye 64 or AS-14B) is an electro-optical variant with a daylight television seeker. The Kh-29TE is the export variant, the Kh-29TM an enhanced variant. The Kh-29TD is another EO variant, possibly equipped with a thermal imaging seeker.

Kh-58 anti-radiation missile was developed during the 1970s to arm Soviet Frontal Aviation defence suppression aircraft, especially the newly developed MiG-25BM Foxbat.

The design was clearly inspired by the joint UK-French developed HS-Matra Martel series, as the Soviet design is almost identical in configuration, cardinal design parameters and size.

The Kh-58 was later integrated on other strike aircraft, specifically the SU-24 Fencer, the SU-17/22 Fitter, and Su-25 Frogfoot, these requiring an external emitter locating pod such as the Vyoga or Fantasmagoria.

The Kh-58 airframe uses 30KhGSA stainless steel extensively, and OT4-1 titanium alloy is employed for the wings and tail surfaces. The Avtomatika PRGS-58 anti-radiation homing seeker is mounted in the nose, it generates steering signals for the SAU-58 guidance, which also uses inertial unit inputs for midcourse guidance.

The 149 kg blast-fragmentation warhead employs an ROV-20 active laser proximity fuse with a backup contact fuse, both armed by the guidance unit.

The rocket motor develops 6,000 kp of thrust during the initial boost/climb phase, and once this 3.6 sec burn is completed the sustain phase thrust rating of 1,000 kp is produced until burnout.

The Kh-58 can be carried externally using the AKU-58 launcher, or internally using the UKVU-50 ejector.

In a typical delivery profile the missile flies a semi-ballistic trajectory on inertial guidance, switching to passive anti-radiation homing as it nears the target emitter. The baseline Kh-58 introduced during the Cold War had a cited range of up to 120 km.

It was replaced by the improved Kh-58U which had a better PGS-58M seeker and a range of up to 250 km for a high altitude supersonic launch.

The current production Kh-58E export variant has a range of 200 km, subject to launch conditions, and likely employs the engine developed for the Kh-58U. The weapon has been integrated on the new MiG-31BM Foxhound variant.

An anti-shipping variant equipped with an active radar seeker and analogous to the Matra-BAe Sea Eagle has been proposed.

The latest export variant offered is the Kh-58UShKE, which is slightly shorter than the Kh-58E, uses shorter span wings, and has a range of up to 245 km.

It is equipped with a new wideband seeker design capable of acquiring emitters operating between 1.2 and 11 GHz, and can also home on CW (continuous wave) emitters in one band.

The Raduga Kh-59 Ovod/AS-13 Kingbolt was developed to provide a standoff weapon capable of operating in heavily jammed environments. It is a direct equivalent to the AGM-142 Popeye series of standoff weapons carried by Israeli F-16Cs, US B-52H and Australian F-111C.

Initial development envisaged a television and datalink guided weapon similar to the HS-Matra TV Martel, using the Kh-58/AS-11 Kilter airframe and Kh-29TE Tekon-Elektron Tubus-2/Granit 7T-M1 television seeker system, but this idea was abandoned due to the long range high speed high altitude profile airframe and propulsion optimisation of the Kh-58.

Better design

The new missile needed to perform better at lower altitudes and speeds, and provide a range of at least 40 km.

The subsonic missile design employs two solid rockets for propulsion, a tail booster, and a fuselage sustainer with a pair of nozzles exhausting from the sides of the fuselage.

Once the booster burns out, it is jettisoned, exposing the radome for the missile datalink, which carries TV imagery to the launch aircraft and receives operator steering commands, both using the Raduga APK-9E Tekon pod.

Missile control is effected by trailed edge surfaces in the cruciform tail, with distinct folding canards used for stability. The missile airframe is constructed with stainless steel and light alloys. An AKU-58-1 launcher is used.

The Raduga APK-9E Tekon pod employs a number of key components no longer built by Tekon-Elektron in the Ukraine.

These include the X-band 1DV1-401AMK pulse mode command uplink transceiver and its gimballed and stabilized antennas, the SB-1A solid state FMCW analogue TV downlink transceiver, the PK-9M pod and the IT-23M cockpit display for the system.

Israel Military Industries (IMI) has revealed a previously unknown air-to-ground missile. The missile, Whip Shot, is intended for hitting soft targets such as a person or vehicle in an urban combat environment, at a cost of under $40,000 per missile (compared to other, more advanced missiles in air-surface use).

The new missile is based on an old IMI-produced rocket, which rides on an optic ray. The total weight of the missile is 15 kg, which makes it possible to install on even tiny aircraft or a warhead weighing 6 kg.

The missile has no independent homing system - the operator controls its flight from within the aircraft, as is common in second generation missiles.

UK future program

The UK’s Future Air to Surface Guided Weapon (FASGW) is being developed as a family of guided weapons comprising of a light and heavy missile systems, improving the Royal Navy’s armaments to equip the future Naval Vertical Lift aviation systems.

In the immediate term, FASGW will improve the firepower and effectiveness of the Royal Navy Surface Combatant Maritime Rotorcraft program (SCMR), currently consisting of the Sea Lynx carrying the Sea-Skua missile.

UK MoD considers meeting the broad FASGW requirements with modified versions of existing missile systems, comprising the Lightweight Multi-Role Missile System (LMM) anti-material guided missile rocket developed by Thales UK (designated FASGW-Light).

The lighter version will utilize a modified Thales ‘Starstreak’ missile system, to be used primarily against small surface targets such as rubber dinghies or for precision attack of unprotected targets on board surface vessels and on land.

For the heavier weapon, MBDA’s Sea-Skua IR missile represents the heavier weapon class, offering longer range and effective anti-ship capability required by FASGW (Heavy).

The combination of FASGW Light and Heavy is expected to be capable of defeating the wider threat target set encountered in today’s maritime and littoral theatre of operations.

As part of the CW Assessment Phase the Lightweight Multi-role Missile (LMM) is being designed by Thales UK’s Belfast site, with low cost being one of the key drivers.

The missile uses proven laser beam-riding guidance and propulsion system derived from the Starstreak air defense missile.

Unlike the Starstreak employing the kinetic energy of the sheer impact as kill mechanism, LMM uses a small explosive charge in the warhead, to engage small targets at sea, on the ground, or in the air-anything from FIAC/FAC, landing craft to wheeled or medium armored tracked vehicles to unmanned air vehicles (UAVs) and helicopters.

The missile is designed for use from very small platforms, including airborne UAVs, and has zero recoil when fired. It was recently demonstrated fired from the Fry UAV system, a derivative of the Herti UAV.

The missile, sealed in its canister, consists of a two-stage motor, warhead and safe arm unit, together with guidance and control equipment. Skid to turn commands to the canards in the nose give extremely accurate guidance of the missile.

The blast fragmenting shaped charge warhead, coupled with the proximity fuze, provides the required level of lethality against the target set defined for the weapon. The system will also be offered with a family of warheads to provide maximum effect against the wide target set out to ranges of around 8km.

Initially the missile will be offered with laser beam riding guidance but there will also be a semi active laser (SAL) variant.

Taurus KEPD 350 (kinetic energy penetration destroyer) is a long-range air-to-surface missile developed and manufactured by Taurus Systems. The company is a joint venture between LFK-Lenkflugkörpersysteme (EADS/MBDA) (67 per cent) and Saab-Bofors Dynamics (33 per cent).

The cruise missile system is in service with the German (Luftwaffe) and Spanish Air Forces. The high precision stand-off guided missile system can penetrate through dense air defence systems and destroy the hard and deeply buried stationary and semi-stationary military targets on ground.

The missile tackles targets, such as air base facilities, bunkers, port facilities, command, control and communication stations, ammunition storage facilities, bridges, ships in ports and runways.

Long-range missile development

The German Federal Office for Defense Technology and Procurement (BWB) contracted Taurus Systems for the development of the high precision stand-off guided missile system in 1998. Successful tests on the image assisted navigation system of Taurus KEPD 350 were conducted in June 2001.

Taurus Systems conducted free flight tests on the missile system in Denel Overberg Test Range, South Africa, in November 2002. The test was led by Wehrtechnische Dienststelle 61 and the German Air Force. Series production of the Taurus KEPD 350 missiles for Luftwaffe began in 2004.

The air-to-ground guided Taurus KEPD 350 missile system has an overall weight of 1,400kg. It has a length of 16.7ft, wingspan of 6.7ft and diameter of 3.5ft. It falls under the MTCR category two weaponry.

The missile is made of modular sections which can be configured based on the individual missions. Its electronic systems are also modular. APCON has supplied the missile seeker electronics.

The Taurus missile is suitable for day and night and all weather deployment. It has low observability and terrain masking features for survivability. The modular design and reliability reduce the lifecycle cost of the system.

The missile carries about 481kg of inert multi-effect penetrator, high sophisticated and target optimized (MEPHISTO) dual stage warhead system for superior target penetration. The ignition system of the warhead is based on programmable intelligent multipurpose fuse (PIMPF).

The programmable fuse is designed with layer counting and void sensing technology. It was developed by TDW Gesellschaft für verteidigungstechnische Wirksysteme.

The blast and fragmentation capabilities eliminate the collateral damage to civil facilities near the target. The stand-off and precision capabilities of the missile and deployment range of more than 350km ensure maximum safety to the aircraft and crew.

Taurus KEPD 350 is powered by Williams P8300-15 Turbofan engine which provides the missile with a cruise speed of about Mach 0.6 to 0.95 at very low altitudes.

The missile has a range of up to 500km (270nm) which is about 15 per cent more than the ones propelled with JP10 fuel.

Navigation of the missile is controlled through Tri-Tec navigation system. It combines data from an inertial navigation system (INS), MIL-global positioning system (GPS), terrain reference navigation (TRN) and infrared seeker based image based navigation (IBN) sensors.

The missile can also navigate long distances without the GPS subsystem. It is equipped with an integrated mission planning system to determine its flight path.

Chinese capability

The C-101 is China’s first indigenous supersonic cruise missile. This design is analogous to Soviet first generation supersonic cruise missiles, but is a unique design employing ramjet propulsion in an arrangement most akin to the Bristol Bloodhound SAM.

The missile uses a pair of jettisonable solid rocket boosters which accelerate it up to Mach 1.8. upon which the 180 kN ramjet sustainers are started and the missile accelerates up to its cruise speed of -Mach 2.0.

The sustainers are fuelled with 200 kg of aviation kerosene. The cruise altitude is programmed at 50 metres AMSL, and terminal closure to target from a distance of 5 km to impact is at 5 metres AMSL. Range is cited at 45 km.

The pulse Doppler active radar seeker operates in the 2 centimetre band. A 300 kg semi-armor piercing warhead is employed. Hydraulically actuated canards are used for pitch control, and tail surfaces for roll and yaw control. An unusual feature is the dorsal and smaller ventral vertical stabiliser fins.

IOC was achieved during the 1990s, with the weapon used as a replacement for the HY-2 and YJ-6 while the PLA awaited the delivery of newer Russian missiles. The surface launched C-101 has been reported deployed on Heku/Komar class and other fast missile boats, the air launched variant on the H-6 Badger, H-5 Beagle and SH-5 LRMP.

China has developed a powered smart bomb that is thought to be called the KD-88. It is about the same size as the C-802 anti-ship missile (which is 21 feet long, 360mm in diameter, 1,500 pounds, with a 360 pound).

China is not offering it for sale yet, so details are scant. The weapon has been seen carried by Chinese aircraft. The KD-88 appears to have an infrared (heat sensing) or TV guidance system and a turbojet engine similar to that found in other missiles, like the YJ-83K.

Such a system appears to have a range of at least a hundred kilometers, and the ability to hit small targets. Some have been seen with what appear to be radar homing sensors. That would make it ideal for taking out anti-aircraft systems, aircraft carriers or headquarters.

The KD-88 has been shown most frequently with larger aircraft, like the JH7A. The SU-30 could probably handle it as well.

The JH-7 is a 27 ton, twin engine aircraft, with a 40 foot wingspan. It is underpowered, and only has a five ton bomb load. But these new precision weapons would make the most of the JH-7, which is used mainly by the Chinese Navy.