Downing drones: Why mobile ground-based air defence is resurgent

Small, fast, manoeuvrable and available to any aggressor, small unmanned aircraft systems (sUAS) are the new front that has opened up in military conflict. As instruments of warfare, drones range from commercially available models bought over the counter and modified to custombuilt and improvised devices, as well as hunter-killer military drones. All can be deadly or, at the very least, capable of capturing valuable intelligence data that can be used to great effect by an enemy. “It is challenging to deal with a very small object that is moving slowly or hovering, or can move at up to 30m/s,” says Matthias Diem, head of strategy and business development at Rheinmetall Air Defence AG. “Variable speeds make them hard to detect, and there are even small jet-propelled drones that can fly extremely fast. A successful counter-small unmanned aircraft system (C-sUAS) must have a sound mix of sensors.”

“The threat can start with small off the shelf drones that anyone can buy and go up to larger sizes like the Reaper,” adds Thomas Broch Sommerfelt, chief engineer for C-UAS. “This is not a black and white world.” Furthermore, the versatility of drones must be matched by countermeasures that are equally adaptable to different threats and can be deployed quickly in any type of environment. This is why Rheinmetall has been working on a mobile C-sUAS system that integrates all of its vast knowhow in the fields of sensors, effectors, data gathering and analysis.

Quick, clean and deadly

The mobile C-sUAS system offers an integrated all-in-one solution for monitoring, identifying, and intercepting current and future mini- and micro-sized unmanned aerial systems. It has been designed for use in highly controlled airspaces and under stringent peacetime engagement conditions, such as at airports and public events. “We have secure critical assets, like military installations and air bases, and the solution is very usable for detection and identification on non-cooperative drones,” says Diem. “It can also be equipped with kinetic and non-kinetic effectors. A unit with radars, passive emitter locators, and electrooptical verification sensors can operate in a vehicle outside the perimeter to increase the range of detection sensors and provide temporary protection.”

“In military conflict, convoys of heavily armoured vehicles need to be protected from drone attacks launched from very close range, so mobile vehicles with turrets with air defence guns and two missiles can be a good defence,” he adds.

Whether operating as part of an integrated network of sensors to protect a large site such as an airport, or operating as mobile protection for a convoy, Rheinmetall’s mobile system can be configured to a user’s exact requirements, thanks to its modular design. The package includes a panoramic phased array search radar that is optimised to detect small targets and an electro-optical sensor to identify and track detected targets. If classified as a threat, a target can be engaged either with non-lethal effectors, jammers or kinetic weapons.

Thanks to the Skymaster Command and Control system, countermeasures can be selected automatically, and the targets prioritised to ensure that the most immediate threats are neutralised first. “The data from all of the sensors is being used to create situational awareness and provide a complete local picture laid over a map,” says Diem. “The threat evaluation algorithm can tell which drone will attack first and Skymaster will assign a weapons system. It is fast and automatic but always with a person in the loop.”

Whether it is a jamming system operated strictly within the parameters laid down by national and international law, or a cloud of tungsten alloy shot into the air from a 35mm gun, the system ensures that drones are stopped in their tracks.

“Drones are a gamechanger in the military context,” says Diem. “Air superiority is often thought to be enough, but there is often a big gap in air defence, which is why you need dedicated sensors to detect and then defeat drones. What we are seeing is a renaissance of ground-based military air defence.”