Airport Drone Mitigation
Part 6: So, Is Jamming a Viable Solution for Airports?

Why Study Jammers?

As a reminder of why we’re looking at jamming in this series of blogs, it’s clear that many airports either have no C-UAS or believe they have one, when in reality what they really have is merely a drone ‘detection’ system, which does not ‘counter’ the drone at all. Traditionally, there have been 3 broadly defined ‘conventional’ solutions when it came to countering rogue drones: kill, capture, or jam. Kinetic “kill or soft capture” solutions are not an option, given the threat of collateral damage and the cessation in airport and airline operations until the cat-and-mouse game is over. This left just one traditional solution – jamming. But is jamming a viable solution for airports?

In previous blogs in this series, we’ve looked at what jamming is, how jammers operate, the consequences of jamming all four frequencies, the types of jammers available, how effective they are at airports and how a rogue drone will respond when a jammer is used against it. As I pointed out in my last blog (When a Drone is Jammed…) , authorised airport security and police must decide if jamming is the right solution for them and whether they should purchase a jamming system, or look at a new generation of emerging technologies to mitigate the threat from a rogue drone.

Which Leads us to Five Key Questions…

There are many questions airport security and aviation police should ask when considering if jamming is a viable solution for an airport. To summarise what we’ve talked about in this series of blogs, I’ve answered what I deem to be the five ‘key questions’:

Q1. Which jamming technique is best?

For jamming to be truly effective, it is necessary to employ noise jamming, with three possible techniques: spot, sweep and barrage. Spot jamming can’t deal with drones which are frequency agile, as it focusses on a single frequency. Sweeping jamming only focusses the energy on one frequency at a time, so is unable to follow the pattern of a frequency agile drone. Barrage jamming is less powerful on each frequency, decreasing its effective range, but it does target all four frequencies used by drones and therefore is the most effective at jamming most drones.

Q2. That’s great! So, is jamming all four frequencies an option?

Jamming all four frequencies (or even only one frequency) will likely have a detrimental effect on aircraft and airport operations while the jammer is being used. It may also lead to major collateral effects on businesses and homes around the airport. Jamming all 4 frequencies is an option, but it will probably result in grounding all aircraft and diverting flights. The airport must bear in mind the cost to airports and airlines for suspending operations – not to mention the negative publicity from such an incident!

Q3. Understanding the risk, what type of jammer is best suited to an airport?

Each type of jammer – omnidirectional, directional or targeting – will have a different impact on airport operations, aircraft, local businesses and communities. Omnidirectional jammers don’t need cueing onto the drone, but they jam everything in a 360° arc, causing the most disruption to an airport. Directional jammers do need cueing onto the drone, but limit the disruption as they only jam in one direction. Both are generally expensive because of the number of jammers needed, the raw power required and the cost of additional sensors to cue the jammers. Targeting jammers are best suited for airports as they cause the least amount of disruption, they’re simple to use – point and shoot – and relatively cheap.

Q4. Okay, so targeting jammers are the best option?

Of all the jamming solutions, yes, this seems to be the least problematic. However, the jammer operator must have direct and unobstructed line of sight with the drone, which is difficult on an airfield with slab sided hangers, terminals, and control towers. Passengers and public will see what looks like a gun being pointed into the air as the jammer operator attempts to get a shot at a fast-moving drone – alarming and likely to attract unwanted attention. Targeting jammers have limited range on a sprawling airfield and don’t protect the air corridors leading to and from the airport where an aircraft is most vulnerable. So, yes, targeting jammers are an option, but using them will still result in the grounding of all aircraft and diverting flights until the potentially lengthy chase is brought to an end.

Q5. If targeting jammers are the best option, what risks are associated with how drones respond to them?

No matter which jamming technique or type of jammer is used and no matter what model of drone is targeted – including commercial, DIY and hacked drones – if the jamming is effective the impact on the drone is the same: the drone pilot’s signals and/or the GPS signal are drowned out. Targeting jammers can be effective against drones but they do not take control of the drone or the pilot. When jammed, the drone will attempt to respond in the way it has been programmed, but in reality, that outcome is unpredictable and completely out of the control of the jammer operator; they can only watch and report on the drone’s response. It may fly back to the take-off point safely, it may fly partway home and land in an unknown location or crash, it may attempt to return home by the most direct route across runways, or fly into infrastructure. The drone may have been programmed to land in the middle of the runway or fly into a terminal, aircraft apron or ATC tower, it may immediately descend and land on whatever is directly under it, it may hover for as long as the battery will last then land or crash, it may have been programmed to fly away and return from another direction, or it may become immediately unstable and crash. If the GPS jamming is effective, it may fly off in an unpredictable direction across runways, until it crashes or lands in an unknown location. Finally, if the drone is functioning correctly, it will eventually move out of the effective jammer range and control, will revert back to the drone pilot, who will be able to continue harassing or attacking the airport.

The Verdict

Having spent over 40 years operating in a security environment and being responsible for operating against (for real and by Red Teaming[1]) and protecting airport facilities, including providing security consultancy to some of the most prestigious locations one could imagine, and with a deep level of technical knowledge and understanding of drones, drone detection systems, drone mitigation systems like jammers, and human behaviour, I’ve come to the following conclusion… In the absence of any other C-UAS technology, I could not justify the use of a kinetic or capture solution and that would leave me with no option other than to use a jamming solution. Of all the types of jamming and jammers, I’d probably choose a hand-held targeting jammer, but I’d still have to stop airport operations by grounding and diverting all aircraft until the situation was under control.

I’d advise owners and directors of airports and airlines, as well as airport operational and security professionals, that there are 2 main issues they must be prepared for as a result of choosing a jammer as a solution:

• Financial and Reputational Impact: You can’t prevent a drone from approaching and getting onto the airfield or into controlled airspace. You can’t predict how long it will take to get a rogue drone event under control. You cannot guarantee that the event won’t happen again, whether immediately or in the near future. Therefore, you must be prepared for the risk of heavy financial losses when a drone stops the operation, and the associated reputational damage that comes with delayed and cancelled flights.

• Risk and Liability Impact: You can’t influence or predict how a rogue drone will respond to jamming. There is a real risk the drone will crash uncontrollably, fly into an aircraft in mid-air, fly into a building inside or outside the airfield perimeter or land in a place that would prolong the operation restarting. Therefore, one must understand the risks and the liabilities which comes should a jammed drone cause damage to infrastructure, aircraft or vehicles or harm aircrew, passengers, staff or the public.

I’d conclude that that a hand-held jammer is the best ‘conventional’ rogue drone mitigation solution, but all things considered, it is not a truly viable solution as it comes with huge drawbacks and the risks are unacceptably high. Therefore, we must continue to scour the horizon for a viable solution from emerging technologies.

New Generation of C-UAS

In my next blog we’ll look at emerging technologies for the next generation of C-UAS in a search for one which takes full control of the rogue drone before it reaches the airport or controlled airspace, so airport and airline operations can continue to function unhindered …

[1] Red Teaming – Using terrorist and criminal techniques to conduct simulated attacks using real weapons and equipment, in real time when the operation is fully functioning, to holistically assess security plans, policies, protocols, systems, equipment and personnel, in which to advise and make recommendations for change.