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In order to defeat railgun projectiles, I wish to create the Electromagnetic Reactive Armor, a defense that fights fire with fire, aka: intercepts the projectiles by shooting out another one, that stops or slows it down.

However, in order to pull this off, we need an "accelerating field" that is capable of speeding projectiles up to high enough velocities, so the vehicle, we want to protect, won't need to have a bunch of small guns sticking out of it in every direction.

How could this accelerating field be created?


marked as duplicate by L.Dutch, sphennings, Frostfyre, Josh King, Vylix Aug 8 '17 at 21:06

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    $\begingroup$ A fast changing magnetic field should do the trick if your counter projectiles conduct electricity well enough. The implementation though ... I have absolutely no idea. That would be complicated. $\endgroup$ – Raditz_35 Aug 8 '17 at 9:22
  • $\begingroup$ I wouldn't call it armor tough, it's more like en.wikipedia.org/wiki/Close-in_weapon_system $\endgroup$ – Maciej Aug 8 '17 at 9:40
  • $\begingroup$ You'd have to use Eddy Currents to produce a magnetic field that opposes the projectile's motion. You'd be "catching" the projectile, in a sense. A demonstration of how this works is with the "Eddy Current Guillotine" $\endgroup$ – DisturbedNeo Aug 8 '17 at 10:57
  • $\begingroup$ I don't think it's possible in real-world physics to slow a projectile using another projectile in this manner, since a single object on its own could never create the necessary field. If you're going to hit the projectile with your own projectile, simply hitting it out the air with some kind of point defence would suffice. To slow it, I believe you'd need, as I mentioned, some kind of "catching" setup that harmlessly slows the projectile to a stop. $\endgroup$ – DisturbedNeo Aug 8 '17 at 11:02
  • $\begingroup$ Isn't this called point-defense? However, the mechanism is a little bit different. $\endgroup$ – Vylix Aug 8 '17 at 21:06

/we need an "accelerating field" that is capable of speeding projectiles up to high enough velocities/

Obviously, you would use pulsed laser air ionization, using the plasma paths created as the rails for your own ad hoc one time railgun.


There is no mechanism I can think of for a homogenous field to accelerate a projectile. Instead, your vehicle will have many fields, each the width of a laser beam. Any one of these lasers will be able to increase intensity to the point that air traversed is ionized.

Ionized air can conduct electricity: it is how the lightning does it. Parallel paths can serve as railgun rails for you to shoot your own projectile.

I envision all of these lasers to be turned on all the time, pointing in all directions. Like a colander placed over a lightbulb. As needed one or more can be turned up to produce the plasma path. Or perhaps they all are that strong all the time.

It would be very easy to see this vehicle coming. Given that the element of surprise is gone, I propose that the vehicle also broadcast sounds which are an appropriate match for the belasered appearance.


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