Precision guided munitions have become today’s norm, especially to overcome averse weather and where targets are close to urban areas.
Smart weaponry shapes the way the military fight wars. Recent conflicts like Operation Allied Force (Yugoslavia), Iraqi Freedom (Iraq), Enduring Freedom (Afghanistan) and Unified Protector (Libya) saw precision guided munitions (PGM) take a lead role. The adversary’s integrated air defence systems as well as government buildings and its media facilities – all regarded as strategic targets were struck by a new generation of air weapons.
Once air superiority had been won, which in Yugoslavia, Afghanistan and Libya was not difficult, the skies are controlled and PGMs can be used at will. Equally as important is the role that PGMs play in the propaganda war. The enemy will use the killing of innocent civilians as a weapon to turn the attackers support. But they have to be targeted correctly. There have been a stream of reports on the Saudi-led operations in Yemen when innocent civilians have been killing and maimed. One instance in late February, saw 40 children perish during a Saudi attack. Whether its down to poor target information, or GPS jamming which several leading players in the Middle East have stated is a serious issue in Yemen, such civilian casualties are acceptable.
Bad weather is another reason why PGMs gives an edge. Lessons from Operation Desert Storm in 1990 and in 1999’s Operation Allied Force when poor flying conditions grounded some of the fighter-bombers, meant there was a need for even smarter PGMs.
The latest thinking on PGM is that munitions technology needs a complete overhaul. In a September 2018 report, the Air Force Association’s Mitchell Institute for Aerospace Studies, stated “there is now a trend towards dynamic retargeting, when combat aircrews take off without actually knowing the kind of target they’ll be concentrating on.” It added, “there aren’t enough aircraft to re-fly sorties just because they weren’t carrying the right weapons, so it’s crucial to develop munitions whose blast effects can be adjusted before release.”
The Mitchell report continues, “The US Air Force needs ‘new effects design concepts such as variable yield, adapted effects, adjustable effects, and systems of employment.” So far the USAF has not officially acknowledged any new PGMs to succed those currently in use.
Converting dumb bombs
There is no need for free-fall bombs or barrel bombs, unless used by a regime such as the Syrian Arab Air Force when killing civilians has been acceptable and often repeated.
The methods generally used are infra-guided/electro optical (IR/EO), laser, radar, satellite, laser/satellite and precision guidance kits which generally come in kit form and strapped to the ‘dumb bomb’.
This was initially done with Paveway series of weapons (Pave is acronym for precision avionics vectoring equipment), which have been successful because no modifications were needed for the aircraft. In the mid-70s, 500lb (226kg) Mk82 bombs were converted into a GBU-12 with a Paveway II nose-mounted laser seeker and fins for guidance, which are still in use today. The 1,000lb (453kg) Mk 83 became the GBU-16 Paveway II but the bigger 2,000lb (907kg) Mk84 GBU-10 became Paveway III which housed a more sophisticated seeker and while it is more expensive it is generally more accurate than a Paveway II.
The Enhanced Paveway II series saw the dual-mode all-weather capability GPS and laser-guided kits attached to all the Paveway II GBU-10 (2,000lb), GBU-12 (500lb) and GBU-16 (1,000lb) series of bombs. RAF Eurofighter Typhoons used the 1,000lb (453kg) EPW II during its first offensive operations on 12 April, 2011 when they attacked targets in Libya while RAF Panavia Tornados were also using the 250lb (113kg) INS/GPS Paveway IV. The latter received its baptism of fire with the UK’s Joint Force Harrier in 2008, and later the Tornado. Meanwhile the USAF remains committed to the GBU-39 Small Diameter Bomb.
A Paveway kit can be attached to a variety of warheads, and consist of a semi-active laser (SAL) seeker, a computer containing guidance and control electronics, thermal battery and control augmentation system (CAS). Completing the weapon are front control canards and rear wings for stability. The weapon guides on reflected laser energy: the seeker detects the reflected light from the designating laser, and actuates the canards to guide the bomb toward the designated point.
Joint Direct Attack Munition (JDAM)
Lessons learnt from the 1990/91 Gulf War, showed there was a need for a ‘adverse weather precision guided munition’ leading to the Boeing Joint Direct Attack Munition (JDAM). The joint USAF/US Navy programme converts 500lb (226kg) Mk82/BLU-111 warhead, 1000lb (453kg) Mk83/Blu-110 and 2,000lb (907kg) Mk84/BLU-109 unguided bombs into smart weapons with a bolt-on inertial guidance system coupled with a GPS receiver.
Before departing on the mission, the aircraft will use its own GPS system to pinpoint the targets and just prior to release will feed the JDAM’s computer with its current location and the GPS co-ordinates of the target. Using the GPS system, the USAF says the JDAM can hit with a circular error probable (CEP) of five metres or less, and if the GPS signal is jammed or lost, the weapon could achieve a 30-metre CEP for free flight times up to 100 seconds.
Being a fire and forget weapon, the aircraft can leave the target area and move on to its next mission. The JDAM also uses an expanded launch acceptance region (LAR) that defines the region the aircraft must be within to launch and hit the target. Paveways I, II, III have significant restrictions on the launch envelope due to the seeker field of view. This means the aircraft has to fly straight at the target when the weapon is launched. If there is a Weapon System Operator (WSO) in the rear seat, as there is in the Boeing F-15E Strike Eagle and its derivatives, he or she can steer the weapon on to the target, with the aid of a data-link. The GPS based flight controls can autonomously adjust its trajectory to hit the target, meaning it can hit targets it has passed over.
Now Boeing is introducing the Laser JDAM (LJDAM) – a JDAM with a low-cost Precision Laser Guidance Set (PLGS) kit that achieves outstanding accuracy and can engage both moving and stationary targets on the ground. This conversion means the 500lb (226kg) GBU 38 JDAM will be known as the GBU-54 LJDAM. JDAMs are used by the bulk of the USA’s bombers: Rockwell B-1, Northrop Grumman B-2, Boeing B-52, Boeing F-15E, Lockheed Martin F-16, F-22 and Boeing F/A-18.
RAF prefers Brimstone
The MBDA Brimstone was declared fully operational on the RAF Tornado GR4 in December 2005, and went onto see service in Iraq and Afghanistan. The weapon, ideal for hitting moving targets, was about to be integrated on the BAE Systems Harrier in 2009, but the jet’s forced retirement in 2010 precluded that. In May 2008, under an urgent operational requirement (UOR), the system was upgraded with a dual mode seeker, allowing a man-in-the-loop capability to reduce collateral damage. During anti-Daesh operations under Operation Shader, the Tornados operated the Brimstone DMS, which along with the Paveway IV was the RAF’s weapon of choice, because of its ability to strike small fast moving targets. The Tornado’s retirement on 31 March, saw the weapon migrate to the Typhoon, which flew its first operational Brimstone 2 sortie on 30 January this year, the day before the Tornado flew its last Shader sortie. The USA has never been interested in fielding European weapons.
Detecting and Destroying SAMs
The Raytheon AGM-88E/F Heat-seeking Anti-Radiation Missile (HARM) is being used by F-16CMs and F/A-18 Growler/Super Hornets. The HARM’s main role is to suppress or destroy surface to air missile radars and radar-directed air defence artillery systems. “The SEAD [Suppression of Enemy Air Defence] will jam the appropriate systems, while DEAD [Destruction of Enemy Air Defence] will destroy,” an F-16CM pilot of the 52nd Fighter Wing based at Spangdahlem, Germany which operates the HARM recently told this writer. Raytheon is now developing a HARM upgrade known as the HARM Control Section Modification (HCSM) which will use a GPS receiver and an improved inertial measurement unit for precision navigation.
NATO relies on the US for the bulk of its SEAD/DEAD requirements but the German Air Force and Italian Air Force Tornado ECRs, are used in this role equipped with HARMs. They have been deployed to operations in Iraq, Libya and Yugoslavia, but NATO’s European and Canadian membership has aspirations to provide 50 percent of the alliance’s SEAD/DEAD capability. Europe’s leading missile/munition company, MBDA has hinted that it has looked at developing its Meteor beyond-visual-range (BVR) air-to-air missile (AAM) as a possible future anti-radiation missile (ARM). If so, it could potentially offer the likes of the Typhoon, Saab JAS-39C/D/E Gripen and the Dassault Rafale fighters with an ability to perform a true SEAD role.
Raytheon is working with Norwegian defence company, Kongsberg to develop the long range Joint Strike Missile in the anti-ship and land attack role. It is the only fifth-generation cruise missile that will be integrated onto the F-35 and will be available for integration on other aircraft intended for offensive anti-surface warfare applications. Initial integration tests are being completed on the F-16, with a JSM specifically designed for the F-35 A/C weapons bay internal carriage.
Meanwhile, MBDA has been working on a FC/ASW (Future Cruise/Anti-Ship Weapon) concept phase for two years now. In mid-March, the missile giant announced the successful achievement of its key review, jointly conducted with UK’s Defence Equipment and Support (DE&S) and France’s Direction Générale de l’Armement (DGA). MBDA said on its website, “The Key Review conclusion will makes it possible to select the most promising missile concepts in order to meet the requirements expressed by both nations’ armed forces. More in-depth studies will now be conducted on these concepts with the aim of identifying the solutions that will be selected at the end of the concept phase in 2020 in order to answer both nations’ requirements for long range anti-ship missions, suppression of enemy air defences and deep strike. A development and production phase should take place in the 2024 timeframe, so that current weapons systems can be replaced in accordance with required timescales.”
The FC/ASW programme was born from converging requirements expressed by both France and the UK for a long range anti-ship capability, as well as the ability to neutralise the most advanced air defences, and house a deep strike capability that can penetrate defences and hit long-distance hardened targets. The FC/ASW aims to replace Storm Shadow/ SCALP air launched cruise missile in operational service in the UK and France as well as Exocet anti-ship missile in France and Harpoon anti-ship missile in the UK.
The introduction of the long range stand-off weapon means that aircraft do not even have to cross into enemy territory to hit the targets. After the young Royal Jordanian Air Force pilot was shot down in his F-16 over Iraq, and subsequently slain in horrific fashion by Daesh, the cruise missile became a ‘must have’ by most Middle East air forces. As well as looking to avoid the loss of civilian life, air forces do not want their pilots having to eject in enemy territory. These weapons can be fired well outside of the range of an adversary’s air defence systems.
MBDA has developed the Scalp EG also known as Storm Shadow (UK) and Black Shaheen (UAE), as well as the Taurus SOW with German Air Force Tornados. The Scalp EG has emerged as a popular SOW with both Egypt, India and Qatar, which will operate the Rafale and reportedly has a range of up to 162nm (300km). The Saudis are using Storm Shadows initially with the Tornado and now the Typhoon, as will Kuwait when they receive their Typhoons. The Scalp/Storm Shadow has been popular with the Middle East air forces because they are largely not bound by International Traffic in Arms Regulations (ITAR). According to a UAE official at the recent IDEX exhibition in Abu Dhabi, “this saves us at least two years waiting to get permission to buy them.”
The US Air Force and US Navy’s preferred SOW is the Raytheon AGM-154 Joint Stand Off Weapon (JSOW). The family of JSOW air-to-surface glide 1,000lb class weapons provide standoff capabilities from 15nm (28km) at a low altitude launch up to 60nm (110km) at a high altitude launch. The JSOW can be used against a variety of land targets and operates from ranges outside enemy range. The Kuwait Air Force will use the JSOW on the new Block III F/A-18E/F Super Hornets when delivered.
by Alan Warnes