Electric Armor

Ch_Omega and others wrote in about a new type of reactive armor in development. As far as I can tell, what they're talking about is essentially large capacitors on the outside of the vehicle, charged up by the vehicle's electrical system. Anti-tank warheads use a shaped charge to create a jet of molten copper that pierces armor, but in this case, when the jet bridges the capacitor plates, it immediately becomes a conductor for X coulombs of current, which effectively vaporizes and disrupts it enough that it won't pierce the vehicle's armor. (Conventional reactive armor does the same thing with explosives.) Interesting idea, if it works.

Comments

Very Effective

[Richard_at_work]

From reports on the BBC (TV not site) this is a very effective armour, and the power is provided by the tank itself, using its usual power supply. This techinology was developed solely in the UK, with the US army being very interested in it.
Apparently a single tank can withstand multiple (10 or more) hits from a RPG when this system is in use, which hopefully will cut down on the threat!

Re:Very Effective

[ericman31]

Actually, tanks like the Challenger (British Army) and the M1 Abrams can withstand RPG hits now, 10 more hits would not be a major issue. My M1A1 Heavy was hit by an RPG during Desert Storm. I didn't even notice until we were recovering and rearming after that mission. This sort of armor would be a tremendous boon for infantry fighting vehicles, which are very vulnerable to RPG rounds and shaped charge HEAT type tank rounds.

Re:Very Effective

[Phanatic1a]

Okay, here's how HEAT rounds work.

You've got a shaped charge of HE surrounding a metal liner that's usually copper. In this picture, you can clearly see the copper liner surrounded by the shaped charge.

When the HE blows, it turns the metal liner into a slug traveling at mind-boggling velocities. This slug is what penetrates the armor.

To replace the liner with a non-conductive material is easier said than done, since the non-conductive material will have to behave similarly enough to a metal to deform appropriately when the shaped charge blows; a ceramic probably won't do the trick. It will also have to be dense enough to matter; polystyrene probably won't do the trick.

And finally, there's a tremendous amount of surplus RPGs floating around. Nullifying those as a threat is a good idea, even if armsmakers develop new kinds in the future.

Re:Very Effective

[ericman31]

I thought it was pretty funny actually. I happen to love Quake, Doom and Duke Nukem. They are totally unreal and let me (when I was in the Army) escape from the reality of my job.

Speaking of computer games that deal with the military, I can see why a lot of folks have unrealistic notions of what a tank, for example can do, and survive, because most of the tactical level games I have seen are very unrealistic. An infantryman with an RPG cannot, repeat not, defeat a main battle tank. An M1 carries two 7.62 mm machine guns, one slaved to the ballistic computer, and 1 50 caliber (12.7 mm) heavy machine gun, in addition to the main gun. The crew of an M1A2 has three thermal imaging systems that all operate independently (driver, gunner and tank commander), and yes thermal imaging can "see" through walls, at night, in the day, raining, clear, yada yada. Dust and fog degrade thermal sights, but then again they degrade daylight sights even worse. A squad of infantry vs. a tank is a losing proposition, for the infantry. Unfortunately most tactical computer games that try to be realistic will make it very possible for that infantry squad to kill the tank.

Re:Ouch

[Phanatic1a]

You have to do more than pierce the outer plate. Basically, the outer plate is charged, and the inner surface is grounded. The cap only discharges when something bridges the plates. 'course, if something doesn't bridge the plates, then it didn't penetrate and you're safe anyway.

Tank crews tend to retain their hearing after being in a tank that's impacted by enemy fire; an APC crew shouldn't have a significantly worse experience, assuming they're not dead or otherwise shredded by spalling.

Re:Another article stolen from Kuro5hin.

[ericman31]

All this speculation is fine and dandy, but how bout some reality.

I was a tank crewman in the Army for 10 years. For the last 3 years I was a Master Gunner. Master Gunners are gunnery and ballistics experts. I was also a tank commander (meaning commander of a single tank and its crew) during Desert Storm.

Reality. The M1A1C, the last tank I served on, weights, with full combat load, 68 tons. An artillery shell, unless it is a direct hit, doesn't bother the tank. It may destroy the crews baggage, which is stowed on the outside of the tank. Possibly it may shatter some of the optics, although the gun sights are protected fairly well. A near miss by a high explosive anti-tank (HEAT) round is no more effective than a near miss by a rifle bullet. HEAT is a shaped charge, it has a 2 kilogram warhead that fires its explosive in jet stream directly in front of the round.

Aside from aircraft, there are two killers of tanks on the battlefield. The main gun of another tank, firing sabot. Sabot (more officially armor piercing fin stabilized discarding sabot long rod penetrator) is a 2 kilogram, 40 mm in diameter, dart of depleted uranium or tungsten alloy steel. It strikes the armor of the tank at a speed in excess of 5000 feet per second (~1520 meters per second). Basic physics tells you that this is a huge amount of energy released in a 40 mm circle. However, if the penetrator is not made of DU or tungsten steel it will shatter rather than penetrate. The other main killer is heavy anti-tank guided missiles, which fire shaped charges from over top of the tank. These missiles fire two charges, one right after the other, in order to defeat reactive armor.

The M1 tank doesn't use reactive armor, it uses laminate armor. Laminate armor is made up of layers of steel and ceramic, and is much more effective than an equivalent thickness of steel alloy. With the M1A1 Heavy (the variant used in Desert Storm) even the main gun of another M1 had difficulty penetrating the M1's armor at 1000 meters (point blank range for a tank engagement) and the M1A1C and M1A2 have armor improved over the Heavy variant.

Shaped charges and artillery have proved extremely ineffective against the M1, which is why the quest for rail gun technology, providing an even more effective kinetic energy penetrator than the current chemical energy main gun.

Re:Looks interesting..

[Stonehand]

Well, there are a lot of areas where peacekeepers would probably love to have this sort of tech. Figure on urban areas in the Third World where small arms, RPGs and their ilk, and maybe mortars / other small support are common, but where your average warlord is unlikely to get his hands on a bona-fide tank or helicopter gunship. In that case, your biggest worries probably are stuff like... ...improvised explosives (and they need to be pretty powerful; the Israelis have lost, what, only 2-3 Merkavas during this intifada, if memory serves despite throwing them into urban zones that /should/ be nightmarish for tanks, in theory) ...mines (for which you might want an engineering AFV and engineer troops) ...RPGS (cheap and common... and if numbers are vastly on their side, they may not need to do much more than immobilize) ...ambushes / betrayals (Sure, I'll lead you to him, just dismount here...)

but you're unlikely to be dealing with, say, a warlord who's managed to get an armored force but has hidden it for all the while.

Re:Charge Time?

[afidel]

did you read the article, it says that the system can stop up to 10 hits without failing.

Re:RPG's $10 and are extraordinarily widespread

[Sycraft-fu]

RPG = Rocket Propelled Grendade. They are rather popular anti-vehicle weapons for gurellia groups.

LAW = Light Anti-tank Weapon. A little 1-use rocket launcher, again for nailing vehlicles.

APC = Armoured Personel Carrier. A vehicle you stick troops in to get them some place without getting shot.

BMP = Don't know what it means but it's a Russian APC.

M2A2 = The Bradley. US light fighting vehicle. It has a small turret (25MM), missles, and holds 10 people. Kind of a beefed up APC made to fight along with the M1A1s.

M1A1 = The Abrams battle tank, with the newer version being called the M1A2. Most powerful tank in the world, and there are very few weapons that can destroy one (espically the A2 variant) in one shot.

T80 = Russian tank. Not as heavily armoured as the M1A2, but still huge.

Re:Another article stolen from Kuro5hin.

[ericman31]

I read the article, and I responded to the folks talking about this armor and tanks. Read the original posts I responded to.

Reading ... it's a useful thing.