Air defence on the battlefield has returned, particularly to counter unmanned aerial systems.
For decades the functions of forward tactical air defence have taken a back seat in many of western militaries. This was particularly pronounced with United States ground forces which had 26 battalions dedicated to the mission in 2004 but deactivated all but nine with seven of those being Army National Guard units. However, the US was not the only military to relegate local air defence to the ‘not a concern’ column. The German Bundeswehr phased out both its Krauss-Maffei Wegmann (KMW) Gepard 35mm self propelled anti-aircraft gun system and its Roland Marder based anti-air missile systems by mid-2010.
However, two international developments brought air defence back into the spotlight – first, was the appearance of inexpensive small unmanned aerial vehicles (UAS) and their use by insurgents as in Mosul, Iraq in 2016. Second was their deployment during the Russian military incursion into the Crimea and subsequent conflict with Ukraine.
The introduction of the small UAS challenges the security of a wide range of facilities and activities including military, public, industrial, and government sites. Military concerns such as airfields and bases are suited to commercial ‘soft kill’ Counter-UAS (C-UAS) systems like DroneShield’s handheld DroneGun or stationary fixed DroneSentinel or tripod Drone Sentry. Bill Kramer assistant vice president C-UAS programs at SRC pointed out; “Larger UAS platforms have adopted these improvements significantly increasing the threat they pose …. The most recent example of this was the Abqaiq-Khurais oil refinery attack where large UAS platforms were used to strike oil processing facilities.” This demonstrates the clear erasure of any practical difference between the UAS and tactical aircraft.
However, the UAS has made protecting forward combat manoeuvre elements from aerial threats substantially more difficult. It must address the small UAS, larger more capable UAS, remote piloted aircraft (RPA) and tactical air. These targets range from lone or ‘swarm’ low signature VTOL UAS operating locally in dense ground clutter to a low and fast strike aircraft or tactical missiles delivering precision ordnance in a coordinated attack. Though the ‘detect, decide, and defeat’ criteria for each may differ, it also is questionable if particularly forward tactical forces can afford to have unique systems to address each of these threats.
First Step C-UAS
The reaction to the somewhat belated recognition of the threat presented by the small UAS drove particularly the Unite States military to initiate a number of accelerated efforts to get CUAS capabilities fielded. The emphasis was largely focused on defeating these UAS despite a parallel concern over the similar inadequacies in short range tactical air defence in general. A notable and almost coincidental exception was the introduction in 2018 of a new proximity fuse warhead upgrade and introduction of in-flight guidance for the General Dynamics/Raytheon Stinger missile. This new fusing not only enhances the missiles effectiveness against aircraft and helicopter targets but also can be used against the UAS/drone. Threat detection for the Avenger/Stinger SHORADS relies on the AN/MPQ-64 Enhanced Sentinel X-band radar from Raytheon/Thales. Although it has a range of 74km, being trailer mounted it must be set up and operates only stationary. This limits it effectiveness covering fast moving manoeuvre units leaving Avenger/Stinger teams reliant on visual search.
MADIS and Tactical Soft Kill
The US Marines moved smartly in introducing a true tactical CUAS capability that could be deployed. The Light Marine Air Defence Integrated System (LMADIS) uses a pair of Polaris MRZR light vehicles and can detect, locate, identify, assess, and neutralise a range of UAS platforms. Lee Dingman, president and COO at Ascent Vision, the MADIS provider explained: “It combines radar, electro-optics, and electronic warfare technologies to reliably provide an umbrella surveillance coverage out to 5-6 km both while stationary and on-the-move. It then can conduct a ‘soft kill’ of the radio frequency controlled or GPS navigation reliant UAS often by jamming these signals. With a loss of control the UAS may crash or be forced to abort its mission.” LMADIS gained significant attention when it was revealed that it had successfully deterred a hostile UAS on 17 July 2019 while operating from a US warship in the Persian Gulf.
SRC also offers its Silent Archer counter-UAS system. Bill Kramer assistant vice president C-UAS Programs describes it as “a tailorable system-of-systems providing a layered sensor and mitigation capability to effectively ‘detect, decide, and defeat’ each of the five groups of unmanned airborne threats.” They use multi-dimensional detection, tracking, classifying, identifying, and disrupting using EO/IR, RF and radar with non-kinetic electronic warfare responses. The Army, in January 2019, contracted SRC to provide a mobile system to counter small, slow and low flying drones. The US Air Force followed in June with a sole source bid to SRC as part of its Medusa system.
Building off its MADIS, US Marines GBAD (Ground Based Air Defence) is an initiative bringing drone, aircraft and cruise missile detection, alerting, and tracking together on a single mobile platform. Funds are budgeted for 28 Joint Light Tactical Vehicle (JLTV) mounted systems with a 2022 initial fielding. The first GBAD iteration, MADIS 1, consisting of a Mark 1 system focused on counter-fixed, rotary wing and non-kinetic UAS defeat while the Mark 2 appears strictly focused on detection and both kinetic and non-kinetic defeat of the UAS. A Marine Corp 26 March 2020 Request for Information (RfI) calls for an effective range at least 4km in a mature non-development system. Systems are required for testing by mid-2021 and low rate production in mid-2022. The RfI seeks solutions “that can be integrated into the MADIS”.
The MARCORSYSCOM PEO Land System PM-GBAD also lays out a MADIS Future Weapon System that reflects these two vehicles improved to provide a turret launching for Stinger, direct fire weapon (calibre unstated), multi-functional EW, and EO/IR optics. The Mk 2 substitutes a 360 degree radar for the missiles. The Marines have also experimented with a directed energy weapon, the Compact Laser Weapons System CLaWS as an additional option for counter UAS. A prototype is undergoing evaluation. Based on results it could be considered for incorporation into future GBADs.
US Army M-LID to E-LIDS
Leonardo DRS and SRC were solicited in March 2019 by the US Army to provide the Expeditionary Low, Slow Small Unmanned Aerial Vehicle Defeat system (E-LIDS) which is targeted against Group 1, 2 and low-end Group 3 threats. This is an extension of its early M-LIDS (Mobile-LIDS) mounted on the MATV 4×4 vehicle. Filling an urgent requirement, M-LIDS included two platforms with a .50 machine gun MOOG unmanned weapon station. One is equipped with a telescoping mast electro-optic sight with thermal and day cameras, zoom imaging, and laser ranging to identify a threat. The second uses a radar to detect and track with electronic jamming leading to a ‘soft kill’. As it prepared to deliver these first systems for testing, DRS was already looking to enhance the capabilities of the initial designs. Edward House, business development manager Land Systems suggested that “improvements could include up-gunning to a 30mm auto-cannon which would not only better address kill effect against the UAS but expand its ability to engage other aerial and ground targets.” The 30mm effectiveness is increased with Northrop Grumman’s new programmable fused warhead that offers air-burst, point detonate, and delay allowing effective engagement of a wide range of targets. House continued: “The vehicles could even incorporate ‘carry and launch’ of its own UAS designed to attack and neutralise, destroy or capture a threat UAS.”
To fill its short range air defence (SHORAD) gap in its manoeuvre forces, the US Army is looking to a new system that integrates existing, non-development sensors and weapons on to the Styker A1 8×8 armoured vehicle. Leonardo DRS’s solution was selected in mid- 2018 and delivered test prototypes in around 12 months. The IM-SHORAD will be capable of addressing fixed and rotary wing aircraft and Groups 1- 3 UAS threats. It is configured with the RADA Multi-mission Hemispherical Radar (essentially the same radar used in the MADIS) with AESA (active electronically scanned array) antenna positioned on each corner of the vehicle for detection, locating and tracking threats. Armament consists of a MOOG RlwP turret with a 30mm auto-cannon and 7.62mm coaxial machine gun plus a quad-launcher for Stinger missiles and a dual Lockheed Martin Longbow Hellfire missile launcher. A L3 WESCAM MX-GCS independent panoramic EO/IR stabilised sight with laser ranging and designator provides hunter/killer search and engagement. Identification Friend or Foe IFF interrogator is positioned forward on the turret to eliminate fratricide engagements.
IM-SHORAD is intended as an “interim” solution to provide 144 systems for four air defence battalions. Testing is underway with a production decision the end of 2020. This said, the US Army requirement for SHORAD capability is significantly higher with its air defence battalions currently equipped with the 1990’s Avenger. The Army defines the current system as ‘interim’, however, DRS and MOOG are using the inherent adaptability of the RlwP, open system architecture and capacity of the A1 Stryker to explore enhancements to sensors and weapons anticipating technology advances and updated tactical requirements. Doug White business development manager at MOOG Space and Defence Group indicated that “upgunning is forward. Change out of different missiles is simply basic mechanical and software/electrical fire control interface. Reconfiguring with simple modification kits has already been demonstrated.”
Howler and Coyote
Raytheon’s Coyote is the latest CUAS fielding but also one with potential for other mission applications. An early version was used by the US Marines in 2018 to provide UAS hard kill in conjunction with its initial GBAD. Subsequently the company developed a Block 1B version with an RF seeker and proximity warhead for the Army. It uses Ku band radio frequency radar (KRFS) for drone detection and interception. Concurrently it developed an improved Coyote Block 2 with a turbine jet engine, improved sensors and a blast fragmentation warhead with air speed increased to 200 knots (370 kmph), extended loiter time, greater 10-15 km range, and enhanced lethality. This system called Howler couple to its KRFS achieved IOC (initial operational capability) in June 2019 addressing a Joint Urgent Operational Need Statement (JUONS). In March 2020 the Coyote was approved for international sale.
John Hobday, Coyote business development lead explained that “the KRFS high fidelity volumetric properties make it ideally suited for detecting and discriminating aerial targets including those operating extremely low near ground clutter. It, thus, can address a wide range of targets and threat scenarios. In addition, the Coyote operator maintains positive control via a two way data link allowing it to be retargeted or even aborted even after launch.” The system is adaptable to a variety of platforms addressing fixed site defence or mobile use. It has been demonstrated with KRFS and launcher integrated onto a single carrier like a medium tactical truck providing a mobile relocatable system or on a JLTV or other armoured tactical vehicle, and on a transportable “pallet” for stationary fixed site defence.
Hobday emphasised: “Coyote’s inherent design adaptability, modularity and low cost lend itself to potential application to other missions and targets. For example a Block 3 version with greater loiter capability is being explored.” This adaptability could allow a pod launcher to be loaded with a mix of Coyote missile versions each configured for different roles and targets, like other air threats, armoured vehicles, command and communications nodes, and even opposing air defence systems. With such a configuration the system expands its combat utility and a multi-mission capability on a single platform.
The Ballistic Low Altitude Drone Engagement system (BLADE) is another US Army CUAS effort. It is directed toward providing the ability to detect, track, identify and engage small UAS threats using the existing CROWS remote operated weapon system. CROWS with .50 calibre machine gun is currently mounted on tactical vehicles ranging from the MATV and JLTV to the Stryker and M1A2 MBT. BLADE adds a radar and fire control software facilitating hitting the moving target to the existing thermal and day video sighting. Technology prototypes have been tested and the Army has begun to reach out to industry to begin move toward future production systems. BLADE could provide a capability to individual tactical vehicles to defeat the small UAS (sUAS). Whether this addition will also potentially also enhance CROWS primary capability of engaging ground or other non-UAS threats nor the cost and complexity implications remain unclear.
Another piece of the US Army’s anticipated future tactical air defence system is the Low-cost Extended Range Air Defence which is intended to provide a smaller more tactical interceptor missile system to address subsonic cruise missiles, unmanned aerial systems and, one may assume, also threat aircraft. This air defence tier between the SHORAD and Patriot High/Medium air defence missile is a critical area and one without a US solution. A Multi-Mission Launcher (MML) has been an internal development by Army research labs since 2012 for the role. MML provided a truck mounted fifteen tube launcher that would accept a number interceptor missiles types. By 2018 in had demonstrated its ability to fire the AIM-9X air-to-air missile, AGM-114 Hellfire, a Lockheed-Martin Miniature Hit-to-Kill (MHTK) kinetic kill missile, and Raytheon/Rafael Tamir missiles. However, in October 2019 BG Brian Gibson in charge of the Army’s air and missile defence modernisation indicated MML would not be further pursued and the interceptor developments were ‘paused’. What direction efforts to fill these deficiencies remain unclear.
Lessons from the .50 CAL
The realisation that the UAS arose as a serious tactical and operational threat has sparked a variety of initiatives by various agencies across all of the services. These tended single mission systems focused solely on countering the UAS, and only Groups 1, 2 and 3 at that. However, at least at the tactical level, the UAS is merely an additional aspect of broader aerial threats. Particularly given the ever increasing interconnection of various aspects of today’s battlefields, countering the UAS is viewed as an additional, albeit new element facing SHORAD. It has brought the need to equip and train for self air defence back to the ground force.
The original purpose of M2 .50 calibre machine guns on tactical and combat vehicles was to provide organic unit, local anti-aircraft defence. This was lost in western armies thanks to the guarantee of air superiority and the seeming shift to specialised high technologies. The UAS has back that aerial threat.