V/SHORAD radars: A resurgence

Driven in large part by the increasing proliferation of drones and loitering munitions, recent years have seen a resurgence of interest in very short-range/short-range air defence (V/SHORAD). This article examines recent developments in the field of V/SHORAD radars, as well as the direction these innovations are taking, and their growing significance on the modern battlefield.

During the Second World War, fire control radars began to replace or complement optical directors used by some larger (around 40 mm) anti-aircraft artillery (AAA) VSHORAD batteries, both ashore and afloat. Smaller (such as 20 mm) cannons continued to rely on optical direction and local control. Cueing and warning was provided by longer-range radars.

By the 1960s, fire control radars, by now more compact and reliable, were integrated for V/SHORAD on vehicles or weapon mounts. The Soviet-designed ZSU-23-4 Shilka, mounting a 1RL33 ‘Gun Dish’ radar providing fire control for four 23 mm cannons, and was used effectively in the 1973 Yom Kippur War. In the 1970s, Soviet vehicles such as the Osa (SA-8 ‘Gecko’) and Strella-10 (SA-13 ‘Gopher’) integrated surface to air missiles (SAMs), with fire control radars. Soviet and later Russian-designed V/SHORAD systems and their integrated radars were widely adopted, including in by some countries that otherwise used Western hardware, as exemplified by the 96K6 Pantsir-S1 (SA–22 ‘Greyhound’) with the UAE.

The need for surface warship self-defence against Soviet missiles led to a new generation of naval V/SHORAD systems such as the US Phalanx, armed with a 20 mm six-barrel gatling cannon, and the British Sea Wolf SAM, which saw combat in the Falklands in 1982, a conflict that demonstrated the continued importance of V/SHORAD capabilities. Sensor architectures designed to defeat long-range high-altitude threats could be inadequate against close-in targets.

Today, V/SHORAD radars retain an enduring requirement to provide point defence against fixed and rotary-wing manned combat aircraft and missiles. Against threats that are likely to range from missiles to the smallest Group 1 (less than 9 kg) uncrewed aerial vehicles (UAVs), V/SHORAD is increasingly overlapping with counter-rocket, artillery and mortar (C-RAM) and counter-uncrewed aerial vehicle (C-UAV) missions. Urgent operational requirements from forces worldwide have shown the increased importance of these capabilities.

Expanding the familiar concept of the common operational picture (COP) to include C-UAV and C-RAM tracks remains a challenge. In this regard, V/SHORAD radars and sensor networks have to detect and defeat swarms of drones. Moreover, their small radar cross section (RCS), low altitude (often in surface clutter), terrain masking and low speed, makes UAV threats difficult to distinguish and so may be filtered out or be dropped by Doppler gates rather than being tracked. General James ‘Scorch’ Hecker, commander of US Air Forces Europe, said in Aurora, Colorado on 12 February 2024, “If they come in at a hundred feet, you can’t see them with a regular radar because you don’t have line of sight over the horizon because of the curvature of the earth.”

V/SHORAD radars increasingly operate as part of dispersed multi-mission, multi-spectral, sensor open architectures, incorporating precision fire control radars along with passive and distributed sensing, especially optronic and infrared (IR) technologies that can be co-located on an individual weapon mount or platform, providing inputs to fire control. V/SHORAD radars are integrated with kinetic and non-kinetic effectors, the latter including high-energy lasers (HELs), high-power microwaves (HPMs), and directional jamming. In Ukraine, backtracking from V/SHORAD radar tracks locates UAV launch locations for targeting with artillery fire or infantry patrols, requiring UAVs to fly evasive low-altitude routes before climbing to their operational altitude. Ukraine has introduced Western V/SHORAD radars into its sensor architectures through donations of Western systems, as well as other projects such as the FrankenSAM programme, managed by the US Air Force.

General Hecker, in an online conference on 31 July 2024, included SHORAD among “skill sets that had atrophied in the 30 years after the end of the Cold War and we are getting that built up again”. In July 2024, US defence analyst Michael Kofman, returning from Ukraine, identified, “the leading problem is increasingly air defence, both short range systems to cover the front line, and long-range air defence to defend cities. … A deficit of air defence has led to pervasive Russian UAV reconnaissance behind the front line and increased success rates in strikes”.

Armed forces that had given up much of their V/SHORAD capability after the Cold War are currently reinvesting in it, including the armies of Belgium, Germany, and Norway. The 2024 announcement that the German Army has ordered 19 Skyranger 30 systems (with an option for a further 30) based on the Boxer 8×8 platform, underlined the country’s plans. At sea, the international naval experience of Houthi attacks in the Red Sea has increased interest in economical capabilities to detect and defeat such threats.

The US Army is building back its V/SHORAD capability and the US Marine Corps is organising new Littoral Anti-Air Battalions. Both services are introducing new V/SHORAD weapons systems that are integrated with international radar designs. Secretary of the Army Christine E. Wormuth told an audience in Washington on 27 February 2024, “We in the Army have got to do more and more and more on UAS, counter-UAS in terms of investing in those systems.”

US Air Force interest in SHORAD reflects its move towards agile and dispersed combat operations in the western Pacific and NATO’s flanks. None of the US services’ current force structure goals includes the numbers of SHORAD sensors that would be required to enable defence of dispersed operations. General Hecker, on 31 July 2024, identified sensor integration as critical. “The hardest part is trying to make sure you can detect things over an area the size of NATO that are down at 200 feet, without putting a Sentinel radar every five miles across the country. You need to have a master integrator that takes all the sensors and set up a kill chain with low-cost effectors that will take them down … not an easy job.”

Emerging technologies

The use of active electronically scanned array (AESA) technology in V/SHORAD radars offers improved data quality (increasing accuracy and decreasing false alarms) and higher reliability, reducing force structure and support requirements. Many AESA radars, without switching between multiple search modes, can simultaneously detect both large, high, fast, and small, low and slow threats. Software-based radars can make responsive changes to algorithms rather than requiring hardware modification, and time-consuming testing.

Multi-spectral sensor architectures integrate data from different sensors into a single fire-control quality track. Most recently, in June 2024, in a demonstration at the Yuma Proving Ground, Arizona, long-range radars, remotely located, used networked systems to transfer – including to V/SHORAD systems – fire-control quality tracks and provide a remote engagement capability against targets including swarming UAVs.

Examples of V/SHORAD sensors using passive radio frequency (RF) detection technology include direction-finders, such as the 11 LiveLink Aerospace Passive Detection and Ranging (PDAR) systems selected in 2023 for an urgent capability requirement for shipboard defence by the (UK’s) Royal Navy. To identify loitering munitions through their control frequencies and manned aircraft through their communications, Ukraine’s “Troops arm themselves with spectrum analysers to detect signals from Zala, Orlan and Supercam UAV types,” Kofman reported. Ukraine has also used cell phone technology to create improvised networks of acoustic sensors, able to detect the sounds of UAV engines. As General Hecker described, “They grabbed 8,000 cell phones, and they put them on six-foot poles, and they put them all around Ukraine and they put a microphone like this next to it so they could hear the one-way UAVs coming overhead.”

Forward area radars face an intensive threat environment. In Ukraine, radars are targeted by jamming and face kinetic threats – artillery and attack drones or special operations – targeted by electronic support measures, which can force deployed radars to displace, disrupting coverage, to avoid Russian action. Michael Kofman wrote that this, “makes forward deployed long-range air defence a high-risk proposition … persistent Russian ISR behind the front lines is a growing challenge”.

The multiple sources of radar and network technologies being used for V/SHORAD by Ukraine makes interoperability problematic. The intense jamming by both sides in Ukraine is challenging for networked radars and other sensors; similarly, GPS jamming has made precision geolocation and gridlocking in mobile operations more difficult. Fratricide remains a significant issue; substantial numbers of both Ukrainian and Russian UAVs have been lost to friendly fire. This is a fairly common problem for drone operations, and is not limited to Russia and Ukraine – in May 2024, various local news outlets reported that some 40% of UAVs destroyed by Israeli forces in its Gaza operation were friendly.

Passive defence cueing – providing warning of incoming threats – can be provided by SHORAD radars. Long-range radars can provide warning over networks such as MADL (Multifunction Advanced Data Link) but not every system can have a receiving terminal; warning messages need to be geographically specific to prevent widespread disruption. US forces in Syria and Iraq in 2023–24, were attacked in over 170 incidents – 114 of them by UAVs – as well as mortar and rocket attacks. Forward deployed radars provided up to several minutes warning although terrain masking and congested airspace, including friendly UAV operations, often reduced warning time. British SHORAD assets from 12 Regiment Royal Artillery carried out counter-UAV operations, though the sensor systems involved have not been disclosed.

The US experience

General Randy George, US Army Chief of Staff, said in Washington on 27 February, “We are transforming in contact when it comes to counter-UAS in the Middle East, which means we are getting all of our capabilities forward with users, developers and testers and we are transforming as we go because the battlefield is changing that quick.”

An example of this change followed the defeat of Houthi UAVs over the Red Sea, which required an unsustainable expenditure of high-cost naval SAMs. This has led to the US Navy and Defense Innovation Unit (DIU) Counter NEXT initiative. Its June 2024 solicitation to industry called for “a kinetic defeat solution for group 3+ UAS” [up to 600+ kg] which includes many attack drones. It must be “more cost effective” than current capabilities, with five prototypes available to be tested within 12 months and integrated into existing combat systems and support systems. The S-band Raytheon AN/SPY-6 family of radars has already been demonstrated in the counter-UAV mission.

Developed by the US Army Combat Capabilities Development Command (DEVCOM) Armaments Center, the Ballistic Low Altitude Drone Engagement (BLADE) Multi-Domain Autonomous Precision Targeting System (MDAPTS) is currently undergoing prototype testing. Designed for use against Group 1 (under 9 kg) and Group 2 (under 25 kg) UAVs, BLADE provides a multi-spectral (radar and optical) VSHORAD capability for the Common Remotely Operated Weapons Station (CROWS), mounting 12.7 mm to 30 mm weapons. BLADE’s radar and fire control software makes it possible for it to engage targets autonomously, with the operator “on the loop” (able to abort an action) – a capability that has previously been used with larger C-RAM systems such as the Phalanx. BLADE’s radar has a directional jamming capability, enabling non-kinetic UAV defeat. BLADE was deployed to Saudi Arabia in 2023 for training exercises.

Another adaptation of AESA radar technology to the CROWS mount is the MSI Defense Solutions Electronic Advanced Ground Launcher System (EAGLS), mounted on a light truck. The system was ordered by the US Navy in April 2024. It uses the Leonardo DRS RPS-40, an S-band AESA radar with a 10 km detection range as mounted on US Army M-SHORAD vehicles. It is deploying armed with a quad-launcher for laser-guided BAE Systems Advanced Precision Kill Weapon System II (APKWS II) 70 mm guided rockets, but can operate with multiple effectors.

Turning to industry for V/SHORAD sensors

The high tempo of US military requests to industry for technologies including V/SHORAD radars demonstrates the increased priority of their multiple missions. A US Marine Corps request for proposals (RFP), in February 2024, called for unspecified advanced technologies capable of conducting counter-UAV. In March 2024, the US Army issued a request for information (RFI) to industry for a “turreted gun-based” system, able to counter Group 3 UAVs, including both active radar and optronic sensors that can be elevated above a 10 m tree line. In July 2024, the Marine Corps issued an RFI for capabilities against Group 1 and 2 UAVs that would include passive radio frequency detection at squad and platoon level and the ability to receive threat warning notifications from radars. A July 2024 RFI to industry looked to demonstrate technologies that would be able to defeat Group 1-3 UAVs in electronic warfare (EW) environments.

In July 2024, the Army announced that it would hold a competition in FY 2025 for a new flat panel array radar to be integrated into their vehicle-mounted Mobile-Low, Slow, Small-Unmanned Aircraft Integrated Defeat System (M-LIDS). In FY 2025, the Army plans to start a C-UAV (and eventually full SHORAD) version of its Northrop Grumman Integrated Battle Command System (IBCS), currently entering service with PATRIOT long-range air defence systems, designated IBCS-M (Manuever). It will be able to merge tracks from multiple sensors and operate in forward areas linked by a self-healing network making extensive use of artificial intelligence. The Army has also expressed interest in integrating C-UAV capabilities on unmanned ground vehicles (UGVs), which will require adapting networked sensor capabilities.

International V/SHORAD radars

In service since 2016, the Saab Giraffe 1X (its designation refers to its 1 m² antenna size) X-band 3D AESA radar provides 360° coverage. A compact lightweight design capable of installation on a light truck, it is capable of operating while on the move. The Giraffe 1X has an instrumented range of 75 km, can detect Group 1 UAVs in surface clutter at 4,000 m and is capable of tracking up to 600 aerial targets. The Giraffe 1X includes Saab’s Enhanced Low, Slow and Small (ELSS) functionality to acquire UAV targets while minimising false alarms, available to other Giraffe series radars through software upgrades.

The Giraffe 1X is capable of being integrated into multiple V/SHORAD architectures, including Saab’s Mobile Short-Range Air Defense (MSHORAD), ordered by the Swedish Ministry of Defense in 2024, armed with the RBS 70 NG, and will mount some Giraffe 1X radars on BVS 10 tracked vehicles. Export customers for the Giraffe 1X include the UK (11 systems ordered in 2023, when deliveries started) and Latvia.

The Sea Giraffe 1X is adapted for naval V/SHORAD applications while retaining functionalities developed for larger Sea Giraffe radars. It has been integrated with sensor suites on German Navy Brandenburg class frigates and Finnish Navy Pohjanmaa class corvettes and on the British research ship Patrick Blackett.

Introduced in 2016, the Thales GroundMaster 60 is a compact SHORAD system intended to provide the capabilities associated with the medium-range GroundMaster 200, currently in action in Ukraine. The GroundMaster 60 is a 3D S-band radar with an instrumented detection range of 80 km and is capable of being mounted on a static mount or a light vehicle, and operating while moving. The first customer was the Kingdom of Saudi Arabia, for use with its MICA VL and Mistral SAMs, and has been negotiating for industrial participation in follow-on production. Armenia has been identified as a potential customer, providing a capability of defeating attack drones and replacing Soviet-era V/SHORAD radars.

The Leonardo Tactical Multi Mission Radar (TMRR), introduced at the Eurosatory 2022 defence exhibition, has reportedly entered production for an undisclosed export customer. It is a C-band AESA radar with a 40 km instrumented range and a detection range of 7,000 m for small UAVs and 20 km for combat aircraft. Weighing less than 50 km, four AESA arrays can be integrated together on a single system for 360° coverage.

International V/SHORAD radars in integrated systems

The Norwegian-designed Kongsberg National Manoeuvre Air Defence System (NOMADS) SHORAD system was introduced at the Eurosatory 2024 exhibition. Designed to be mounted on a wheeled or tracked vehicle chassis, the NOMADS’ Danish-designed Weibel Scientific XENTA-M5 AESA 3D X-band radar has an instrumented range of 75 km, and can detect Group 1 UAVs at 10 km. The radar’s frequency modulated continuous wave (FMCW) capability allows detection of hovering UAVs in ground clutter through detection of the rotors’ micro-Doppler effects.

The NOMADS is compatible with multiple SAM types including the Diehl IRIS-T and Raytheon AIM-9X-2 Sidewinder. On-board communications include Link 16 connectivity. The Norwegian Army is due to receive an initial batch of six vehicles with at least four reportedly already delivered, while The Netherlands is looking to order up to 18 vehicles, and Germany is considering providing the system to Ukraine.

Also introduced at Eurosatory 2024, the BAE Systems Tridon Mk2, for land and naval applications uses on-mount radar integrated with a BAE Systems Bofors 40 mm L/70 cannon, capable of firing the Bofors 3P programmable munition, in order to engage a range of targets including aerial threats.

The Rheinmetall Skyranger 30 and Skyranger 35 turrets, are being offered with on-board radar options that include Hensoldt Spexer 2000 Mk III X-band radar with tracking range of around 40 km and the S-band Rheinmetall Italia Oerlikon AESA Multi-Mission Radar (AMMR), with a detection range of 20 km against combat aircraft and 5 km against small UAVs. Both radar types use small flat panel antennas, and on the Skyranger turret, five are used to provide 360° coverage. Similar approaches to the SkyRanger – mounts integrating guns, SAMs, multi-spectral sensors and capable of using multiple types of on-board radars – include the Turkish Aselsan Kokurs, which is armed with twin 35 mm cannons.

At the lighter end, Israel’s General Robotics offers the Pitbull remote weapon station for C-UAV applications. This primarily uses an optronic sight, but can be optionally provided with a radar. It has been integrated for naval applications and with the Israel Aerospace Industries (IAI) Jaguar and REX Mk II unmanned ground vehicles (UGV) to function as low-risk VSHORAD platforms. With a detection range of up to 5,000 m and an engagement range of 500 m against moving targets, the optional radar can also provide a directional jamming capability against UAVs. Israel has reportedly made extensive use of directional jamming against Hezbollah UAVs in 2023–24.

The increasing overlap of V/SHORAD with the C-UAV and C-RAM missions has required new approaches in expanding the capabilities of V/SHORAD radars and sensors. Palmer Luckey, the founder of Anduril, has been quoted saying that the US is now embracing “non-traditional” defence firms, which has been demonstrated by the use of international V/SHORAD radar designs on US systems. General Hecker said on 31 July 2024, “We cannot afford to have to allow 32 countries in NATO to buy their own thing and then make it interoperable afterwards…It is not necessary to tell them the systems to buy, but rather the capabilities they need to have…which need to be open architecture.” How this will apply to V/SHORAD radars and sensors is perhaps the most immediate impact of the changes in defence investment and force structures that are taking place in the wake of recent technological advances and combat lessons.

David Isby