Innovation and Adaptation

Defence Against the ‘Drone’ Arts

By Greg Rowlands April 5, 2018

‘The decisive weapon in war has always been known, if but in a crude and undeveloped form, in the last war.’ B.H. Liddell-Hart

Scenario 1: A light infantry platoon advances cautiously without tank support[1] along a narrow rubble strewn street in a regional town, recently occupied by an extremist group.[2] Then with no warning a swarm of flying attack drones appears 100 meters forward of the lead rifle section. Each semi-autonomous quad-copter[3] carries a nanoexplosive device, which when detonated acts as an anti-personnel grenade. As two-dozen+ ‘flying nano-grenades’ hurtle towards the rifle platoon, a prescient Section Commander does not hesitate in ordering the rifle section to open fire. The drones are too close to call for indirect fire support, but accurate rifle and machine-gun fire destroys most of them. However, some drones penetrate the platoon’s defensive line and detonate deadly payloads amongst the soldiers.[4] The soldiers are wearing advanced light-weight body armour, which provides some protection from the blasts, but many are wounded. Moreover, the swarm attack was only a diversion from the drone ambush (dronebush) massing down a side street on the platoon’s right flank. Fortunately, the quick-thinking Platoon Commander had anticipated their flanks were insecure and reorientated the platoon into all-round defensive posture. This time there were more flying attack bots, but even with mutually supporting machine-gun, 40mm grenade and rifle fire a few of the drones cause more casualties. The platoon survives the ‘dronebush’, but they exhaust half of their ammunition and have many injured soldiers to evacuate.

Scenario 2: After the lead section (as per Scenario 1) identified the initial kamikaze drone swarm vectoring towards them, the grenadiers fired 40mm ‘acid’ rounds with proximity airburst fuses into the cloud of bots.[5]  The quick-acting highly corrosive acid is optimised to melt drone components, so this volley of acid grenades quickly defeats the leading drones. Then as the remainder close to within 30 meters, soldiers equipped with rifles fire spigot anti-drone rounds, which deploy nets disabling several drones mid-flight.[6]  The few drones that approach to within 15 meters are engaged with gas-operated rapid-fire ‘glue-ball’ guns.[7]  These guns use paint-ball gun technology optimised to fire polymer balls filled with quick-setting sticky glue that blinds drone sensors and obstructs rotor systems, so they fall from the sky. Then as the ‘dronebush’ masses on the right flank it is severely depleted by accurate, withering fire from two Anti-Drone Gun Systems (Drone Phalanx Detachment) from the Battalion’s Anti-Drone Platoon.[8][9] The all-electric Drone Phalanx consists of a millimetric radar targeting system and a 7.62mm mini-gun mounted on a tracked chassis, similar in mass to a quad-motorbike.[10] Spigot drone nets and 40mm acid rounds further thin out the lethal swarm and several bots that breach the defensive perimeter are wrecked by a fusillade of glue balls.  So in this alternative scenario, some soldiers are hit by stray glue balls in the counter-penetration fight, but none are wounded and the platoon retains its first-line small arms ammunition load. The platoon then continues the mission.

While the ambush scenarios are speculation, the reality is that drone swarm technology is being developed and counter-drone systems are considered essential to defeat them.  So it may only be a matter of time before Australian soldiers are confronted with advanced drone attacks in future conflicts.  As Liddell-Hart correctly points out, decisive weapons are seen in an undeveloped form in previous wars, then feature in the next war in a more advanced configuration.[11] There are early indicators of this in the Middle-East, where ISIS modified commercially available fixed-wing drones to bomb targets. Therefore, it follows that more capable drones designed to conduct close combat swarm-bombing analogous to the ambush scenarios could eventuate.[12] Moreover, innovative munitions and weapon systems tailored to defeat drone threats will continue to emerge.[13]

The first ambush scenario highlights that massed small arms fire, infantry combat tactics and world-class leadership may not be enough to defeat a fast-moving drone swarm,[14] whereas the second scenario illuminates how leveraging technology could be the unstated eleventh Principle of War.[15] Counter-drone technologies can yield effective defence thus enabling the infantry platoon to survive the swarm.[16][17] However, while new technology will be a vital part of the solution, counter-drone combat doctrine and tactics will also need to evolve for warfighters to practice and perfect. [18]

End Notes:

[1] In this scenario many of the streets are too narrow for tanks to manoeuvre effectively or safely in the town, so the platoon must rely on its own resources to achieve the mission.

[2] Regional- meaning somewhere well north of Australia where a well-funded extremist insurgency has seized population centres some-time in the second decade of this century.

[3] Once set on an attack vector, these drones are able to navigate their way to the target without human control inputs, which makes it more challenging to disrupt drone remote command links.

[4] Once the attack drones are among the soldiers in their defensive position the soldiers are unable to shoot them down with small arms due to the very high risk of fratricide.

[5] A proximity acid blast round would need to be optimised for use against mechatronic targets only. Strict rules of engagement would be necessary to comply with Geneva Conventions and to ban the employment of acid munitions against human combatants.

[6] Anti-drone spigot rounds contain a capture net that when fired deploys five tethered segments that extend and spin towards the targeted drone(s). The spinning net envelops the drones in flight causing them to crash.

[7] Several light-weight ‘glue-ball’ anti-drone weapons are carried per section for short-range anti-drone engagements. Like paint-ball technology used for entertainment, glue balls are not lethal to humans but may be effective in disabling moving drones with exposed sensors and moving parts. These ‘proposed’ weapons may be essential in urban operations where drone attacks could have very short engagement ranges or may fly among the soldiers.

[8] This would be a miniaturised version of a Naval Phalanx but optimised for land combat operations. It is envisaged that such a system could also be mounted on Army vehicles.

[9] An Anti-Drone Platoon (ADn Platoon) could be a new force structure requirement in light of emerging drone threats.  The ADn Platoon would be equipped with heavier anti-drone weapons, much the same way that Anti-Tank Platoons within Support Company were equipped. These heavy anti-drone weapons could then be task organised with Combat Teams to optimise combined arms effects.

[10] The Drone Phalanx semi-autonomous system operates in pairs and is trailed by an electric semi-autonomous tracked logistics drone.  This LogBot hauls extra mini-gun ammunition, replacement high-capacity lithium-ion or solid-state batteries and solar voltaic rapid recharger panels to extend its patrol endurance.

[11] An example of this is how primitive tanks and early aircraft appeared in the First World War with technology limitations, but then in World War II these combat systems were far more capable and decisive in many battles. So too may be the development trajectory for military drone technologies.

[12] Could include attack drone swarms equipped with shaped-charge nanoexplosives or multi-explosively formed penetrator devices designed to defeat armoured vehicles.

[13] Includes anti-drone laser weapon developments.

[14] Small arms may still be required to destroy airborne drones in some circumstances, so training soldiers to shoot down drones with rifles and machine-guns should be considered for future shooting training competencies.

[15] An Eleventh Principle of War is proposed, as arguably, Leveraging Technology has been an enduring and decisive factor during war. Therefore, consideration should be given for this eleventh principle to be enshrined in foundation warfighting doctrine. The other ten Principles of War include: Selection and Maintenance of the Aim, Concentration of Force, Cooperation, Economy of Effort, Security, Offensive Action, Surprise, Flexibility, Sustainment and Maintenance of Morale.

[16] Electromagnetic anti-drone weapons designed to disrupt drone command signals might also feature as part of the drone defensive toolkit. However, advances in cryptography and autonomy could realise uncertain results in terms of drone control signal disruption, so direct kinetic effects might provide greater mission assurance in disabling threat drones. It may be worth trialling drone electronic counter-measures (DECM) for close force protection, similar to how CIED technologies function.

[17] Sentry drones could also assist with close combat defensive measures.  Air-to-air ‘dog-fights’ may see a class of drones optimised to destroy threat drones in mid-air, before they advance too close to own force elements.

[18] Infantry minor tactics and all-corps defensive measures will ultimately need to adapt to emerging threats from increasingly lethal drones and autonomous systems.



Greg Rowlands

LTCOL Greg Rowlands is an infantry officer with 27 years of Army service. He is a graduate of the Army Command & Staff College and the Capability & Technology Management College.

The views expressed in this article are those of the author and do not necessarily reflect the position of the Australian Army, the Department of Defence or the Australian Government.

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