Punch from the air.

On-going demands for effective fire support for ground forces in both conventional and urban warfare, and for minimum collateral damage and casualties, will sustain the need for airborne weapon platforms for the foreseeable future. However, in view of the threat posed by current air defence system developments, these aircraft will need capable air-to-ground guided weapons to provide accurate warhead delivery from a relatively safe standoff distance. In the longer term, these weapons must deal with both fixed and moving targets, by day and night, regardless of weather conditions.

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The wide range of air-to-ground ordnance delivered by carrier-borne aircraft is well illustrated by the weapons clearance of the Boeing F/A- 18E/F. Aside from its air-to-air weapons, the lightweight General Dynamics M61A2 20mm Gatling cannon, four types of mines, the IMI Tald decoy and the Boeing AGM-84D Harpoon, the Super Hornet is cleared to use the seven-tube 70mm LAU-68 rocket launcher, the 225-kg Mk 82, the 450-kg Mk83 and 900-kg Mk 84 bombs, the 340 kg Mk 77 fire bomb, the 250 kg CBU-72 with three BLU-73/B fuel-air explosive submunitions, the 222-kg Mk 20 Rockeye submunition dispenser with 247 M118 bomblets, and its replacement, the 340-kg CBU-59, with 717 BLU-77 bomblets.

Turning to guided ordnance, the F/A-18E/F is also cleared for Raytheon's 225-kg GBU-12, the 450-kg GBU-16 and 900-kg GBU-24 Paveway series, the Boeing Jdam family, the TV-guided Lockheed Martin AGM-62 Walleye ERDL (extended-range data-link), the anti-radiation Raytheon AGM-45 Shrike, the Raytheon AGM-65 Maverick and the Raytheon AGM-154 Jsow. Future plans include the Lockheed Martin AGM-158 Jassm and the Boeing AGM-84K Slam-ER.

Guided Rocket Projectiles

Although such activities are unpublicised, it is clear that the pioneers in guided rocket projectiles are the Israelis, who for some years have been making precision rocket attacks on pre-selected civilian vehicles. Since an unguided delivery accuracy of one metre would require a launch range of less than one kilometre, such strikes are almost certainly made by having some form of emitter manually applied to the targeted vehicle, and an appropriate homing rocket.

However, such systems are clearly unsuited to the broader tactical military requirement. The general solution (from accuracy and cost considerations) is to have the rocket home on to a coded laser illumination on the target, which may be provided by the launch aircraft, another platform or a designator operated by a forward air controller.

In February 2003 the US Army announced that General Dynamics Armament & Technical Products had been selected to perform the SDD (System Development and Demonstration) phase for the Block 1 unitary warhead version of the Advanced Precision Kill Weapon System (APKWS), scheduled to enter service in 2005. This was to combine General Dynamic's ubiquitous 70 mm Hydra 70 rocket with a laser-based guidance and control system provided by BAE Systems. Confusingly, GDATP now employs the new designation to the whole Hydra 70 family, and the APKWS consequently exists in both guided and unguided forms.

For the Royal Norwegian Navy Kongsberg Defence & Aerospace is developing a guidance and control package for 70 mm rockets that combines GPS mid-course navigation and laser terminal homing. It is intended to use this missile from both surface vessels and helicopters.

Whereas the Hydra 70 has a launch weight of 11.9 kg and carries a 3.95-kg warhead, the Russian 122 mm S-13 weighs 75 kg and carries a 31.8-kg warhead. The laser-guided S-13L is proposed for a range of fixed- and rotary-wing aircraft, and thus could be applied to the Sukhoi Su-33 and Kamov Ka-29.

Looking further ahead, Connecticut-based D-Star Engineering is developing a 90-Newton miniature gas turbine under Darpa funding, which might (it is claimed) convert a 70 mm rocket projectile into a miniature cruise missile. How this engine could be integrated into the existing APKWS body is not clear.

Bomb Kits

The origins of Raytheon's Paveway laser guidance bomb kits can be traced back to 1968. Laser spot-homing provides a precision better than five metres. The Paveway II, which is still in full-scale production, has large fold-out tail surfaces, extending applications to heavier ordnance such as the 900-kg Mk 84 bomb. The Paveway III has an even larger tail, an adaptive digital autopilot and a two-stage guidance system (adding inertial mid-course navigation) to suit long-range toss attacks from low level and to accommodate heavier weapons. By October 2004 some 250,000 Paveway kits had been produced (with Lockheed Martin as second source), and more than 10,000 were used during the US-led invasion of Iraq in 2003.

America's Paveway series has inspired parallel developments in a number of other countries. Russia's series, manufactured by the Region State Research and Production Enterprise, includes the 250 kg LGB-250, the 560 kg Kab-500L and the 1500 kg Kab-500L.

Britain, focused on low-level attacks against runways and armour, was slow to accept the need for the Paveway but introduced it at the end of the 1982 Falklands conflict. It was only in Kosovo in 1999 that British forces discovered that laser homing bombs are useless in the presence of low cloud. That lesson had already been learned by the American services during the 1991 Gulf War, after which satellite (GPS) bomb guidance was quickly developed to provide semi-precise (15-metre) accuracy against stationary targets of known location.

The principal GPS-assisted bomb is the Boeing Jdam (Joint Direct Attack Munition), combining a satellite-cum-inertial guidance tail kit and body strakes, which increase footprint. The GBU-31 is a 900-kg (class) Jdam version with the Mk 84 or the BLU-109 penetrator. The 450-kg GBU-32 is based on the Mk 83 bomb, while the GBU-35 uses the corresponding BLU-110 penetrator. The latest and lightest Jdam is the 225-kg GBU-38, based on the Mk 82 or BLU-111. It was first used over Iraq in October 2004 by US Navy F/A-18Cs of VFA-34.

In tests in 2001, the Jdam, first used operationally in 1999, achieved a 14-metre accuracy with inertial navigation alone, and eight metres with GPS functioning. During the 2003 invasion of Iraq, the 28 satellites of the GPS constellation were continually updated, giving an accuracy of 3.08 metres for 95 per cent of the time. The production of Jdam kits for the US services is currently running at around 30,000 per year, with a unit cost of $ 22,600. The only Russian satellite-guided bomb so far publicised appears to be the 560-kg Region Kab-500S-E.

Following Kosovo, Britain ordered the Raytheon GPS-assisted Enhanced Paveway II/III (EP2/3) as its interim precision guided bomb, which entered service in late 2001. In mid-2003 Britain selected the Raytheon Paveway IV to replace the EP2, with deliveries to begin in 2007. It employs a new Lockheed Martin 227-kg warhead produced by SEI in Sardinia, a Thales multi-event hard target fuze and GPS-aided inertial navigation with anti-spoofing and anti-jamming technology. Growth options include addition of the Lockheed Martin LongShot wing kit.

Other current bomb kit developments include the Umbani (Lightning) project for Mk 82 or Mk 83 bombs, unveiled in 2004 by South Africa's Denel. It offers a choice of guidance systems and an optional wing kit.

Recent conflicts have highlighted the need for penetration weapons. Conventional penetration warheads are becoming increasingly heavier, but the US Air Force has reversed this trend with the 130-kg Boeing-produced GBU-39/B Small Diameter Bomb (SDB). This achieves 75 per cent of the penetration of a 1066-kg BLU-109/B through the use of an advanced casing material, a very slender shape and a guidance system that provides an impact normal to the target surface. Options include the MBDA Diamond Back wing kit, which gives a maximum range of 110 km.

Dispensers and Submunitions

At the opposite end of the spectrum, many softer targets are best dealt with by a submunitions dispenser. In a low-level flyover attack, the bomblet distribution pattern can be used to compensate for weapon delivery errors, but high-level release of the dispenser or a standoff attack demands some form of guidance for the dispenser and/or the submunitions. A leading example of dispensers with smart submunitions is Russia's Region RBK-500 SPBE, which releases 15 Bazalt warheads with dual-band infrared seekers.

The trend to guided dispensers is illustrated by the inertially-guided (now plus GPS) Lockheed Martin WCMD (Wind-Corrected Munition Dispenser) tail kit for the ATK SUU-64/65/66 tactical munitions dispenser (TMD) family. The baseline WCMD is the CBU-103, a guided version of the ATK CBU-87 CEM (Combined Effects Munition), dispensing BLU-97/B bomblets. It was first used over Afghanistan in 1998. The WCMD-ER adds the Lockheed Martin LongShot tail kit, extending range to 75 km.

The Raytheon AGM-154 Jsow (Joint Stand-Off Weapon) is a US Navy-led glide weapon programme with GPS/INS navigation. The baseline 474-kg AGM-154A dispenses 145 BLU-97/B bomblets, but the Navy is also buying the 468-kg AGM-154C with a BAE Systems Broach penetrator, a Thales fuze, and an uncooled Raytheon IIR (Imaging InfraRed) seeker with an automatic target acquisition facility. The Jsow-A was first used over Iraq in February 2001. The AGM-154A * being developed for export will house a 225 kg BLU-111 unitary warhead an insensitive Mk 82.

Recent years have witnessed increasing interest in larger submunitions, partly because they can be used to arm lightweight drones. The 20-kg acoustically guided Northrop Grumman Bat (four of which fit into a TMD) has provided the basis for the laser-homing Viper Strike, which has the advantages of a man-in-the-loop system. The 38.5-kg GPS-guided Lockheed Martin Locaas (Low-Cost Autonomous Attack System) has a turbojet engine, giving a search duration of 30 minutes. It also has an ATK triple-mode warhead, and a ladar seeker, with a downlink under development for man-in-the-loop capability.

Rocket Boost

The lightweight end of the conventional air-to-ground guided missile spectrum is represented by the 45-kg laser-homing anti-armour Lockheed Martin AGM-114K Hellfire II, which is supersonic and has a range of eight kilometres. The latest Hellfire version is the AGM-114N, which has a thermobaric warhead and is used by the US Marine Corps. The MBDA Brimstone is a derivative of the Hellfire, with an active millimetric-wave radar and ATA facility. Other long-range anti-armour missiles include the 50-kg Denel Mokopa, which boasts a range of ten kilometres.

The Raytheon AGM-65 Maverick has been produced with three types of guidance (TV, laser and IIR) and two warheads. It can weigh between 210 and 310 kg and provide a range of up to 24 kilometres. In US service, both the Hellfire and Maverick are to be replaced by the Lockheed Martin Joint Common Missile (JCM), which is to weigh 49 kg but will provide a maximum range of 16 km from helicopters and 28 km from fixed-wing aircraft. It will have a tri-mode seeker and a mission-selectable warhead. Planned platforms include the AH-1Z, MH-60R and F/A-18 series.

Russia's 50-kg laser beam-riding KBP 9M121 Vikhr (AT-16) is a tube-launched supersonic missile with a range of ten kilometres. Replacing the Vikhr is one of the longer-term aims of the KBP Hermes, which was unveiled in 2004. One of a modular family of missiles with tandem boosters, the Hermes-A is the air-launched version, which will employ inertial mid-course guidance and laser spot terminal homing. KBP argues that short-range air defence systems are now effective to twelve kilometres; hence an air-to-ground missile needs a range of 15 km or more. The Hermes-A is typically fired at 15 to 18 km, but other models with larger boosters will be capable of up to 100 km.

The Sagem Aasm (Armement Air-Sol Modulaire) may be regarded as a modular family of bomb-kits, but the modules include a rocket motor. Its two baseline versions employ a 250 kg bomb body, initially with GPS/INS navigation and later with an infrared seeker added. A range-extension wing kit will provide a range of 15 km from low-level and over 50 km from altitude. Deliveries of the Aasm for the Rafale-M will begin in 2006, providing accuracy in the ten-metre class under all weather conditions. The later version, with one-metre precision under day/night conditions, will enter service in 2008.

Anti-Radiation Missiles

The leading Western example of an anti-radiation missile is the 360-kg Raytheon AGM-88 Harm, a supersonic missile with passive radar homing. It was first used operationally over Libya in 1986. The US Air Force credits it with a maximum range of 48+ km, and the US Navy with 91+ km. The AGM-88D adds GPS/INS navigation, in case the target emitter is switched off during missile flight. ATK is the prime contractor for the AGM-88E Aargm (Advanced Anti-Radiation Guided Missile), which will introduce a dual-mode (passive radar and active millimetre-wave) seeker. Trials have been performed with ramjet-powered variants of the Harm.

Russia's closest equivalent of the Harm is the Tactical Missiles' Kh-31PM (AS-17), a 600-kg ramjet-powered missile with a range of over 100 km. The 650-kg rocket-powered Raduga Kh-58E (AS-11) has a range of 160 km.

Cruise Missiles

The use of turbine engines makes possible ranges of several hundred kilometres in missiles that are light enough to be carried by medium-weight combat aircraft. Although the stub-winged 628-kg Boeing AGM-184E Slam (Stand-off Land Attack Missile) is credited with only 100 km, the 675 kg AGM-84H/K Slam-ER (Expanded Response) with fold-out, high aspect ratio wings is capable of 300 km. When the Slam-ER attained operational capability in 2002, it was claimed to be the first in-service missile with an automatic target acquisition facility.

The US Navy also plans to adopt the US Air Force-led Lockheed Martin AGM-158 Jassm (Joint Air-Surface Stand-off Missile), which weighs 1000 kg and has a range of 465 km. The Jassm became operational in 2003, and the Navy plans to buy an initial batch of 453 in FY2007. The next stage of development was originally to have been the 1000-km Jassm-ER, but Lockheed Martin is now studying an extreme range derivative (Jassm-XR) with a range of 1850 km.

One of Europe's principal cruise missiles is the MBDA Storm Shadow or Scalp EG, which has a launch weight of 1300 kg and a nominal range of 250 km, although some reports suggest it is capable of up to 400 km. The Storm Shadow was used operationally in Iraq in 2003, and the Scalp EG will be cleared for the Rafale. A datalink is being developed to allow for an in-flight change of target and to assist in damage assessment. An all-weather seeker is being developed to replace the current IIR system. This Anglo-French missile has also been selected by Greece, Italy and the United Arab Emirates.

The 1400-kg Taurus KEPD350 is a rival development by Eads and Saab Bofors Dynamics, using a TDW Mephisto penetration warhead. It has a range of 350 km, is in production for Germany and was selected by Spain.

Saab Bofors Dynamics is developing the RBS15 Mk 3, which has both radar and IIR for the terminal phase. The MBDA Exocet Block 3 will have a land attack capability and a new turbojet to give a range of over 180 km. The ship-launched MM40 version will enter service in 2007 and it is possible that an air-launched version will be developed.

Europe's only nuclear-armed air-launched cruise missile is the MBDA Asmp, which entered service in 1986. The Vesta (see title picture) programme is aimed at studying new ramjet engines to power the Asmpa--a further development that will be introduced on the Rafale in 2008. The drawing inserted below the Vesta shows the current Asmp for scale comparison. Cruise missiles are to be reviewed in detail in a forthcoming issue of Armada International.