Defeat Terrorist Drones Without Firing a Shot

Lots of news reports today of drones flying over the Eiffel Tower, French Nuclear Plants, and the US Embassy in Paris.  Of course this is irresponsible and dangerous behavior, and the idea of terrorists using drones is mentioned.  How could you stop a terrorist using a drone to carry a bomb or using a drone for some other evil purpose?

Here in the good old USA, we have the state of Oklahoma considering a law to allow you to shoot down drones over your land.  Shooting drones, particularly by homeowners, is not such a great idea as there is a lot of potential for innocent people to get hurt.  It may make sense for the military, who have over 100 years of experience with shooting down flying objects, but not for my neighbor Fred, who has a shotgun and last fired it when he went hunting with his brother in law 10 years ago.

There are certainly less dangerous but effective ways to deal with drones.  Commercially built or homebuilt drones rely on a few things to fly to a target and execute actions.  The loss of one or a few of these capabilities will cause a drone to crash.  Those of us who build and fly drones for fun know this all too well.

1. Sensor input - barometric pressure, accelerometers, compass, airspeed indicators..
2. GPS or GLONASS input.
3. Radio commands.  Radio telemetry back to the operator in some cases.
4. Onboard computer program.
5. Correct operation of motors, speed controls, aerodynamics, and control surfaces.

Almost all of these capabilities are needed for a drone to execute a mission, so how do you deal with an evil drone?

1. Certainly most sensors can be fooled quite easily without physically touching the drone.  I won't detail how to do this but most people with some engineering training could figure it out.
2. GPS and GLONASS can be remotely jammed.
3. Radios can certainly be  jammed.
4. Onboard computers might be hard to disable remotely but there are some techniques that will work with the unhardened commercial flight control systems.
5. Motors, control surfaces and the like are susceptible to damage with very little contact.  A piece of string or a plastic bag in the propeller will stop most drones.  There are lots of ways to stop a drone with similar low tech techniques.

So there is likely a business here for someone to make and sell drone protection systems to high profile targets like stadiums, iconic buildings and monuments, important infrastructure, and government installations.  I am sure we will hear about some startups or military contractors working in this area shortly.

Photo Credit (edited): Flickr