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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.
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!
So, they'll just start making RPGs that don't have an electrically conductive tip. Set the bad guys back a few years, but they'll just find something else to shoot with the existing ammo.
Bummer, nice idea though. Could you get the power up high enough for an arc to destroy just about anything?
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.
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.
In my universe I'm perfectly normal, it's not my fault you don't live in my universe.
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.
Only the dead have seen the end of war.
There seem to be a few misconceptions about how tanks fare on the battlefield and how HEAT warheads work.
First off, a HEAT round detonates several feet away from the surface of a tank. The detonation shoots a stream of molten metal, which impacts the tank and attempts to cut through. Reactive armor helps to defeat this by disrupting the stream of molten metal so that it more or less splatters harmlessly against the tank. The idea is not to MELT or BURN through armor, but to cut it. The jet is moving at immense speeds (Driven by explosives). The bigger the warhead, ie, a TOW vs a LAW, the longer and more powerful the jet is.
Anyway, reactive armor is mainly designed to defeat smaller arms and missiles. It has no effect against Sabot rounds. I've seen a couple of comments about how one would have to know what kind of weapons the enemy has. This is not true. Basically, reactive armor sits on top of standard armor. It's usually fairly lightweight, though bulky.
Electrical reactive armor has the benefit of being easier to replace and make, as well as being a bit less dangerous for the crews to service. The reactive system will fail after one hit, but only in the location of the hit. Even if the tank were to be hit in the same spot twice, there is still a lot of armor to cut through. Reactive armor is basically a cheap, light layer of extra protection from HEAT-type rounds.
As far as the effectiveness of the tank on the modern battlefield, one has only to point to the Gulf War. Regardless of the "Air hype", tanks were responsible for most of the enemy vehicle kills. Tanks will remain a part of the battlefield for quite some time, although they are working on some tanks with fewer crew and lower profiles which also incorporate some stealth technology. Finally, tanks are much cheaper and easier to maintain than aircraft, as well as packing incredible firepower. In many cases, ballistic weapons are superior to guided missiles, as well as beaing a lot less expensive. Regardless of it's "low-tech" design, a Sabot round is by far the most cost-effective anti-armor firepower in use today.
Certainly tanks alone will be easy prey for aircraft, but most nations have a bewildering array of Surface to Air Missiles, which make aircraft a lot less effective. Tanks might get better, and incorporate new technology, but I doubt you will see the demise of the tank anytime in the near future.
For more info, check out: http://www.tank-net.org/
did you read the article, it says that the system can stop up to 10 hits without failing.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Ok, there's some misconceptions here about what a shaped charge warhead does and how it works. Basically there is a very precisely shaped cone of a ductile metal (copper is the usual choice). This is surrounded with explosives which have a high VOD (Velocity Of Detonation). The detonator is at the apex of the cone (away from the target). When fired, the blast wavefront propagates towards the open of the cone symmetrically. It moves so fast and with such a large amount of force, that the metal cone flows like a liquid (but does NOT melt), and is inverted into a long thin jet. This jet is moving on the order of 30,000 - 50,000 ft./sec. This velocity is what give the jet its penetrating power. It is not melted or turned into a plasma, and it does not burn through the target, it simply pushes aside or shatters the target material out of the way. Do a search on the "Munroe Effect". The standoff from the target allows the jet to enlongate and penetrate deeper (thus the long nose on the TOW II).
Shaped charges have been cut into slices and fired into water. Pieces of the jet were recovered with the cuts intact...thus no melting.
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.
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.
In my universe I'm perfectly normal, it's not my fault you don't live in my universe.