Recognising there is a threat is the first step.
Clearly, the US is taking the threat seriously, significantly, the threat is no longer about being observed by ISIS.
Weaponisation is on the threat horizon.
The US Army has recently updated their Techniques for Combined Arms for Air Defense document.
The US Army has clearly recognised the threat from small commercial UAS.
In the security context, the threat from these systems, again, mostly from non-malicious use, but also with an eye to more complex threats, has been clearly recognised by governments.
The first counter, obviously from a non-battlefield view, is regulation.
Many of the safety security domain challenges are likely to be met by regulatory approaches, not all security threats come from those with ill intent.
The regulatory agencies have probably been somewhat behind the curve, as might be expected in any industry where increasing innovation and decreasing cost lead to widespread adoption. There has been somewhat of a ‘Wild West’ feeling in some parts of the market as regulators, insurers and user groups struggle to coalesce around a single sensible and supportable approach.
At the upper end of the regulatory spectrum is the significant volume of work being done for larger unmanned systems by the European Aviation Safety Environment (EASA), UK Civil Aviation Authority (CAA) and Federal Aviation Administration (FAA). There are various research projects, working groups and studies seeking to agree on suitable regulatory frameworks for unmanned systems. EASA has released a technical framework for UAS regulation, the FAA is likely to release their equivalent soon and ICAO is scheduled to release guidance by 2018.
As much of this international work progresses, national regulators have had their own rules in place for some time. In Russia, any unmanned aircraft over 250 grams requires certification and registration, with flight plans submitted to local authorities. After a fairly rigid start, Spain now has weight tiers, any system between two and twenty-five kilogrammes must be piloted by an operator with airworthiness certificate and all flights must be under 400ft within line of sight. Recreational systems in France must be flown under 150ft, and not at night or over populated areas but in the UK, systems weighing less than twenty kilogrammes can be flown by recreational operators as long as they remain below 400ft, within visual line of sight and not over people. Commercial operators must have special permission and operator qualification, read more at the CAA website. This is a rapidly changing environment and no doubt these will have changed by the time you read this.
The Civil Aviation Authority have produced a video for the ‘Drone Code’ and information on registration is available from the Dronesafe Register
Regulation is also being increasingly used with technology solutions.
Most of the larger manufacturers have software that includes ‘geo-fencing’ capabilities that ensure the system cannot be piloted into a ‘no fly’ zone. No fly zones are maintained in real time, in the USA for example, by a company called AirMap.
The software also ensures altitude limits are no exceeded.
For responsible users, this provides a great deal of assurance, they cannot inadvertently fly their aircraft in restriction airspace. With real-time updates available, even temporary restrictions such as those over a forest fire can be incorporated.
In the UK, No Flyzone UK provides a similar ‘request no fly zone’ service.
Some of the most typical causes of accidents that might cause a security issue such as low battery or lost communications are also being increasingly addressed with software, automatic landing upon a defined battery threshold or ‘return home’ on lost communications, for example.
More advanced collision avoidance systems are also increasingly being deployed, especially as large technology organisations enter the market. Intel has recently purchased a number of start-up companies and has combined them with their own technologies to create some very impressive collision avoidance systems. It’s very advanced RealSense technology is now being incorporated into lower cost consumer-oriented systems. For higher flying systems, a technology that utilises cell networks for position tracking has been developed by PrecisionHawk.
Even NASA has recently started testing a US national UAS air traffic control system.
Through a combination of registration, policing guidelines, regulation and technology, together with sensible and lawful operator communities and trade bodies, the majority of non-malicious safety and security threats should be gradually addressed, allowing malicious threats to be the focus, or in a critical location (e.g. airport) safety context, catching the idiots.
Whilst small commercial UAS can be difficult to detect, they are not impossible to detect.
The four main methods are optical/thermal, acoustic, passive RF and radar.
If the system is being actively controlled or transmitting video imagery, it will be radiating RF energy that can be detected and triangulated. For fixed locations, this can be relatively simple to install but more difficult for moving areas or temporary locations.
Acoustic detection uses signature recognition, each drone creates a unique noise. This may not work well in cluttered environments like urban areas, and at extended distances. DroneShield and Alsok are providers of this type of technology.
Thermal and visual detection can use the UAS movement and contrast against a static background. With advanced scene change algorithms this can provide highly effective detection but again, potentially limited in cluttered environments. Small UAS tend to be battery powered and use electric motors, neither well characterised by high thermal signatures.
Radar is the most widely used, but small UAS are still difficult targets to detect, and there is the ever-present problem of bird rejection, Blighter and Kelvin Hughes, both from the UK, have specialist small object detection radars.
The Blighter A400 radar has a published detection range for compact UAV of 6km. The Elvira radar from Dutch company Robin Radar was used to provide security for the G7 Summit in Bavaria last year.
Most of the emergent systems now use combinations of these methods to improve detection results and support identification, classification and evidence gathering.
The next step could be issuing a warning, and nothing more. In Ukraine for example, one tactic used was to avoid attacking the airborne system but instead, track it back to the recovery point and attack the area with indirect fire. The operators, in this case, were far more valuable targets than the systems. Tracking the device back to its recovery point can also be used in a law enforcement context.
Alternatively, a warning may be quickly followed by an attack. The attack could have the intention of simply destroying it, or it could be to disable, capture or even hijack.
Means of defeat can be physical or electronic in nature.
Blowing UAS out of the sky with anti-aircraft missiles or automatic cannons might be OK on the battlefield, but it is expensive and not very well suited to civilian areas where behind target effects might be more serious than the attack.
Beyond highly kinetic means, and accepting geofencing and NOTAMS might only have limited utility against those with determination and malicious intent the two principle means of defeat are electronic and physical.
Electronic attacks might include exploiting a cyber-vulnerability to remotely hijack the device, usually over WiFi or Bluetooth. An example of this is the Maldrone malware. However, with an increasing regulatory concern for flight safety, consumer devices will become increasingly difficult to exploit. Randomised frequency hopping and encryption for control links are being implemented on newer devices. Attacks against the GPS subsystems have proven to be effective but again, secondary positioning with GLONASS and inertial systems may blunt even this.
Active RF jamming seems to be the most common active denial approach in the newer systems.
As can be imagined, it is an increasingly healthy marketplace, with all the defence primes and many SME’s now offering product solutions.
Two such integrated solutions from the UK are the Selex ES Falcon Shield and AUDS.
The Anti-UAV Defence System (AUDS) from Blighter Surveillance Systems, Chess Dynamics and Enterprise Control Systems. Chess Dynamics bring their Hawkeye EO/IR and tracking system that allows the operator to manually confirm and identify the target that has been detected by the Blighter A400 Ku surveillance radar, the Enterprise RF jammer making sure the target is no longer a threat.
The AUDS system is designed to be easily deployable.
The latest iteration of AUDS includes a fourth RF inhibitor (jammer) band and an optical jammer and has been deployed with US forces.
From Selex ES, the Falcon Shield is a similar integrated system.
Other systems include Battelle Drone Defender, Airbus Defence Counter UAV, Thales Squire, Dedrone Drone Tracker, ISL Drone Detection, Drone Dome from Rafael, Diehl HPEM, ART Drone Sentinel, Black Sage UAVX and IAI Elta Drone Guard.
The image below shows the DroneShield
No doubt more will emerge as the market expands.
In Ukraine, Russian forces/rebels have reportedly jammed the OSCE Monitoring Mission Schiebel Camcopters, disrupting GPS. No hard evidence exists for which type of equipment was used but odds on favourite is either the Rtut-BM (Mercury) or Krasuha-4 systems, both from Kret, all speculation of course.
Most of them seem to have effective ranges that max out at approximately 6-10km, less for very small UAS. None of them are optimised for moving vehicles and the market is generally focussing on fixed infrastructure protection.
The Dutch Ministry of Security and Justice, Dutch National Police and the Royal Netherlands Marechaussee (military police) have initiated a number of projects to investigate means of detecting, classifying and neutralising small unmanned ‘drone’ style systems. Read more here and although the project has a modest budget of 1.75m Euros it has attracted a great deal of interest. Less focussed on the military context, the project is looking at drone incursion into controlled airspaces like airports and critical national infrastructure, smuggling in prisons, ‘snooping’ and crimes against the person. More recently, France has initiated a similar project, no doubt in response to the nuclear site overflights that were so widely publicised. The US Secret Service and Department of Homeland Security are conducting field trials of counter ‘drone’ technology in Washington.
Physical disruption can mean many things, simply shooting them out of the sky with a shotgun or automatic weapon is the obvious choice but this method has complications in built up areas and against a rapidly manoeuvring vehicle will be very difficult. One of the Dutch project participants, Delft Dynamics, has developed a concept called Project Drone Catcher that uses another quadcopter to fire a grappling net at the target machine. The net can be tethered to the launch device which allows both to descend under control. Using one drone to destroy another with an intentional collision has also been demonstrated, even eagles have been demonstrated as being able to be trained in the counter UAS role.
Michigan Technology University has developed a net firing hexacopter.
An interesting counter small UAS system has been developed by the UK company, OpenWorks Engineering, called SkyWall. SkyWall uses a physical capture method to ensure drones are removed from sensitive areas.
Although the MoD’s response to the small UAS threat has not been widely publicised, it is not ignoring it. DSTL have a number of projects running under Project BRISTOW. From QinetiQ;
Although the MoD’s response to the small UAS threat has not been widely publicised, it is not ignoring it. DSTL have a number of projects running under Project BRISTOW.
One of the more recent developments using the about to enter service 40mm CTA cannon is the Thales RAPIDFire system, designed to destroy helicopters, unmanned vehicles and combat aircraft.
Lasers will also likely play a role in future battlefield counter UAS.
DARPA is also starting to look at the issue;
The DARPA RFI will include;
- Conceptual designs and performance capabilities, including substantiating preliminary performance data, if available, for the concept of operation(s)
- Technology maturity assessment, including data to substantiate technology maturity and identification of key risk areas requiring mitigation to enable system demonstration
- Program outline for maturing the system to the point where it would be ready for demonstration, including high-level rough order of magnitude (ROM) cost and schedule
- System affordability assessment
- Estimated size, weight, and power requirements
- Ability to address other threats (any part of the targeting chain)
- Ability to integrate third-party subsystems
No doubt, some of the systems above may find their way into the DARPA studies.
Janes has also reported an integrated solution from a UK company called Drone Defender that provides both the equipment and trained personnel.
Because the vast majority of these systems are the standard 30 minute endurance, 1-2 mile range and direct control using WiFi, countering them with active electronic countermeasures seems to be the most common.
Treating them like an IED exposes the idea of re-using the same approach, with priority given to exploiting intelligence to attack the network of enemy personnel that are creating and flying them. It is similar to the methods described above in Ukraine, where instead of destroying the devices, Russian/Rebel forces tracked the devices to their launch points and attacked the operators.