If you are a small country being aggressed against by a rich powerful one, what can you do? Military jets, and even thngs like cruise missiles and military drones, are expensive. But personal drones are pretty cheap.

So buy a bunch of cheap drones. Use the onboard camera to see an incoming jet or cruise missile or military drone. Fly your drone directly into an engine intake opening of the oncoming enemy unit. You lose a cheap drone; they lose an expensive weapon.

Continue protecting your country with drones until the enemy decides the war costs too much, and quits.
-- Vernon, Apr 18 2016

Flying height http://www.technik-...analysis/drone.html
There is a height at which attack weapons fly, and there is another height at which they typically make an attack run (not counting bombers, which were not mentioned in the main text). Since we want to protect from attacks, we only need to consider the second height. Also, if a defense-drone has a parachute, it can fly higher, without need to use the battery for descent. [Vernon, Apr 18 2016]

Altitude would be the probem - drones can't attain the height at which jets operate.

However, a "swarm" of drones trailing strands of titanium wire or kevlar with parachutes on the end (like the WWII PAC air defence system) are effective against helicopters at low level, by rotor entanglement.

The kevlar is slightly less effective, but has the advantage of being invisible to radar, and both are hard to spot on FLIR. LIDAR can spot them but it's not a common fitment on copters, except those tricked out for nocturnal NOE flying.

The concept is to provide a credible threat and force the copter to climb, making it vulnerable to other air defence systems.

The drones that don't intercept the target simply jettison their strands and "go home" to be collected for re-use. Single-use batteries are used to give superior power density for better endurance and payload.

Semi-Baked but not yet WKTE.
-- 8th of 7, Apr 18 2016


No, it has to be a credible threat.
-- 8th of 7, Apr 18 2016


You would need fantastically huge numbers of these to have any effect. They are not going to be able to move into the path of an approaching aircraft or missile - they are simply not fast enough to move appreciably unless the incoming aircraft follows a precise, undeviating trajectory.

So, to take out even a proportion of the incoming hardware, you will need millions of these things.
-- MaxwellBuchanan, Apr 18 2016


50 units can effectively embargo a 1km frontage, echeloned at different altitudes.The concept is to take down at least one of the opposition's ground attack air assets. The system can be deployed forward of the FDL in a concealed position and activated remotely, with unengaged drones returning across the line for recovery.
-- 8th of 7, Apr 18 2016


//50 units can effectively embargo a 1km frontage//

That, I do not believe. Suppose your 1km "frontage" is also 1km high (ie, you're only interested in perversely low-level aircraft). Suppose also that the frontal area of the aircraft's engines is 1 square metre. The odds of any one drone being intercepted by that 1 square metre of engine intake is 1 in 1 million. Fifty drones give you odds of 1 in 20,000.

If each drone can move by 5 metres in any direction in the time it takes an aircraft to change course, you improve the odds to roughly 1 in 200, which is still not great.
-- MaxwellBuchanan, Apr 18 2016


This is specifically an anti-helicopter system relying on rotor entanglement. It's not intended to deal with fast fixed-wing jets.
-- 8th of 7, Apr 18 2016


Ah, right. In that case, problem solved. All you have to do is write a nice letter to the enemy asking them to use helicopters.
-- MaxwellBuchanan, Apr 18 2016



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