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The Miracle Tank Of Legend
strategypage.com ^ | December 3, 2008 | NA

Posted on 12/05/2008 10:08:23 PM PST by neverdem

The U.S. Army is carrying out an aggressive development program to produce a new, lightweight composite armor for its next generation tank. This vehicle, part of the FCS (Future Combat System) series of vehicles, will weigh under 30 tons. The current U.S. tank, the M-1, weighs 70 tons. Composite armor was invented in Britain during the 1980s. The British developers had found that layers of different metals and ceramics made the armor lighter, and more resistant to penetration by solid shot or HEAT shells. The U.S. added a layer of depleted uranium to its composite armor, and produced the most penetration resistant tank armor ever.

Now U.S. Army developers are betting that they can come up with breakthroughs in composite armor design that will produce protection equal to what the M-1 now has, but at less than half the weight. The army developers are doing it by trial and error, making some progress most months. It's still unknown if the new lightweight armor will be there in time for the new tank's debut date in 2015.

The army developers are encouraged by some of the work done during the current war, especially accidental discoveries. For example, troops in Iraq noticed that although EFPs (Explosively Formed Projectiles) go through metal armor, often glass laminate armor (aka glass ballistic laminate armor) will stop them. Troops reported that the EFPs would not go through the bullet proof windows, which are made of glass laminate. However, the glass laminate only works once. When an EFP strikes the glass, the glass "spiderwebs" (shatters laterally and vertically) but it stops the penetrator. Of course it only needs to work once. Troops lives are saved and the stuff can be replaced. At least one unit is experimented with mounting field improvised brackets outside the doors of vehicles to hold the three-inch thick glass laminate armor.

Apparently the glass laminate armor destabilized the explosively forged projectile penetrator and redirected its kinetic energy laterally along the glass armor laminations. This is the principle behind the M-1 tanks chobham armor (a sandwich of metal and ceramic laminates). The ceramic armor is held in a metal armor matrix. As heavy metal "long rod" penetrator or high explosive shaped charge debris streams enter these armor matrixes, they are destabilized. The kinetic energy is diverted laterally from the initial penetrator direction of attack as the ceramics shatter. A plus here is that the Chobham ceramics are jostled by the penetrator's or shaped charge stream's passage and keep abrading until the attack runs out of energy.

Glass ballistic laminate is expensive. One windshield costs several thousand dollars. The lamination process has a high scrap rate. It takes several tries to create one good, large piece of the material. The silica/polycarbonate plastic sandwich is hard to heat evenly and if it is not perfectly shaped a "void" will appear in during the curing process. This creates visibility issues, and troops need to be able to see through the glass. But it was an interesting discovery, and there were others as well.

These are the kinds of problems army armor developers have to solve if they are going to create a "30 ton M-1." In addition to the lightweight composites, the army is also working on improved ERA (Explosive Reactive Armor.) Invented by the Israelis in the 1970s, ERA consists of explosives packaged between layers of sheet metal. When the hot gas jet produced by a shaped charge (of an RPG or missile warhead) hits the ERA explosives, the gas jet is disrupted and rendered harmless by the ERA explosion. Many American M-2 and AAV-7 armored vehicles in Iraq are protected by ERA kits (which cost over $100,000 each). A Stryker ERA kit costs nearly $300,000 per vehicle, and adds 3.5 tons of weight (compared to 2.5 tons for the current slat armor it will replace.)

There are two shortcomings with ERA. One is that, once a section of it explodes, that section is obviously, no longer protecting the vehicle. Also, it takes 50 or more pieces of ERA to protect a vehicle. The other problem is that, when ERA explodes, it expels some metal fragments that can injure nearby friendly troops. There are solutions. CLARA ERA uses several layers of composites (non-metal material) and explosives which, when they disrupt a shaped charge gas jet, only create lightweight chaff. CLARA is much lighter than standard ERA, weighing about an ounce per square foot, versus several pounds per square foot for standard ERA. There is also SLERA (Self Limiting ERA), which uses smaller amounts of explosives to disrupt the gas jet, and less destruction to the section of ERA itself. This also results in lighter ERA. Both these types of ERA are more expensive, and lack much combat experience.

Finally, there is APS (Active Protection System.) These usually consist of a radar to detect incoming missiles, and small rockets to rush out and disable the incoming threat. A complete system weighs about a ton. Russia pioneered the development of these anti-missile systems. The first one, the Drozd, entered active service in 1983, mainly for defense against American ATGMs. These the Russians feared a great deal, as American troops had a lot of them, and the Russians knew these missiles (like TOW) worked. Russia went on to improve their anti-missile systems, but was never able to export many of them. This was largely because these systems were expensive (over $100,000 per vehicle), no one trusted Russian hi-tech that much, and new tanks, like the American M-1, were seen as a bigger threat than ATGMs.

The Israeli Trophy APS uses better, more reliable, and more expensive technology than the Russian Drozd (or its successors.) For about $300,000 per system, Trophy will protect a vehicle from ATGMs as well as RPGs (which are much more common in combat zones.) Israel is the first Western nation to have a lot of their tanks shot up by modern ATGMs, and apparently fears the situation will only get worse. Israel first encountered ATGM, on a large scale, in the 1973 Arab-Israeli war. But these were the clumsy, first generation ATGM. These turned out to be more smoke than fire.

Then there is the use of electricity, flowing through specially designed armor, that stops many types of attacks. There are several other technologies which are, well, quite secret. But it's a combination of new stuff, if anything, that will produce the 30 ton vehicle that can take on an M-1 class tank and win.


TOPICS: Editorial; Foreign Affairs; News/Current Events; War on Terror
KEYWORDS: antitank; armor; compositearmor; fcs; tanks
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To: B4Ranch

Something interesting


21 posted on 12/06/2008 12:42:28 AM PST by JDoutrider (Heading to Galt's Gulch... It is time.)
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To: Future Snake Eater

Ping.


22 posted on 12/06/2008 2:28:41 AM PST by RightOnline
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To: neverdem

bttt


23 posted on 12/06/2008 5:32:01 AM PST by Matthew James (SPEARHEAD!)
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To: kms61

Tandem warheads. Its already been done, including by the Russians.


24 posted on 12/06/2008 6:11:47 AM PST by centurion316
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To: kms61; centurion316
Until somebody comes up with a two stage EFP...

Yes. New RPG-7's with two-stage shaped-charge warheads to defeat reactive armor appeared in Iraq three or four years ago in the hands of jihadis.

25 posted on 12/06/2008 7:18:58 AM PST by lentulusgracchus ("Whatever." -- sinkspur)
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To: archy

ping


26 posted on 12/06/2008 7:36:42 AM PST by B4Ranch ( Veterans: "There is no expiration date on our oath, to protect America from all enemies, ...")
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To: Lil'freeper

ping


27 posted on 12/06/2008 7:39:46 AM PST by big'ol_freeper (Gen. George S. Patton to Michael Moore... American Carol: "I really like slapping you.")
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To: JDoutrider

Imagine being inside a tank and it getting hit by a warhead. If that didn’t literally ring your bell, nothing could. You wouldn’t have eardrums left, I don’t think.


28 posted on 12/06/2008 7:40:57 AM PST by B4Ranch ( Veterans: "There is no expiration date on our oath, to protect America from all enemies, ...")
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To: DieHard the Hunter; kms61
Why not just throw democrats at them?

There ain't nothing in the universe that dense.

29 posted on 12/06/2008 9:12:18 AM PST by mountn man (The pleasure you get from life, is equal to the attitude you put into it.)
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To: mountn man
Why not just throw democrats at them? There ain't nothing in the universe that dense.

Ayup, the density's there all right. It's getting them up to speed that's the hard part.

30 posted on 12/06/2008 9:40:18 AM PST by Smokin' Joe (How often God must weep at humans' folly.)
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To: kms61

Not at all. Ever hear of mirrors?


31 posted on 12/06/2008 9:40:56 AM PST by meatloaf
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To: DieHard the Hunter
Depleted Uranium is very dense, and unlike lead or other elements, it self sharpens as it bores in.

Nasty stuff.

32 posted on 12/06/2008 1:10:40 PM PST by redgolum ("God is dead" -- Nietzsche. "Nietzsche is dead" -- God.)
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To: B4Ranch
Imagine being inside a tank and it getting hit by a warhead. If that didn’t literally ring your bell, nothing could. You wouldn’t have eardrums left, I don’t think.

LOL! Indeed your whole system would be left numb and ringing! Lost enough hearing from close encounters with things that go BOOM to get a C&P rating... Still can't hear worth a damn from that. Can't imagine being entombed in a tin can being slammed with Boom!

33 posted on 12/06/2008 7:15:16 PM PST by JDoutrider (Heading to Galt's Gulch... It is time.)
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To: B4Ranch
Imagine being inside a tank and it getting hit by a warhead. If that didn’t literally ring your bell, nothing could. You wouldn’t have eardrums left, I don’t think.

I have been inside an open-topped armored fighting vehicle when a shaped charge warhead struck us, the explosive jet blowing right in one side and right out the other. We hardly noticed it at the time [taking full-auto RPK fire, among other things] though it would have been pretty rough on anyone standing directly between entry and exit.

I'd also have been less happy to have undergone the experience in a fully-enclosed vehicle such as a tank. A couple of my Israeli pals who have survived impacts from wire-guided AT missles such as the Soviet Sagger/Malyutka tell me I worry too much, that the commander's cupola comes right off [with the vehicle commander in it] and relieves the pressure.

34 posted on 12/10/2008 12:57:36 PM PST by archy (Et Thybrim multo spumantem sanguine cerno. [from Virgil's *Aeneid*.])
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To: DieHard the Hunter
Here’s a “stupid-civilian” question: what’s the deal with “depleted uranium”? What does it do that plain ordinary lead doesn’t do? Does it glow in the dark, or explode-on-impact, or what?

It's not a dumb question unless you don't ask it. DU is both sufficiently dense [like lead] and hard to penetrate either rolled steel or *honeycomb* composite armor very effectly. Indeed, part of the armor layers of an Abrams tank is itself DU, because of that density.

But in addition to being dense and reasonably tough, it's pyrosphoric, which means that as chips or flakes are scraped away, as when it penetrates a resisting armor surface, those chips become extremely hot from the friction and ignite, both setting fire to anything combustable they come into contact with, like ammunition, hydraulic lines, fuel or the vehicle's crew members, but also burn up a great quantity of the oxygen insside doing so.

Watching a typical older US or British tank *brew up* with fuel and ammo aboard is spectacular: after a half minute or so the poweder in the main gun rounds begins to burn off and a jet of flame 20-30 feet high roars out of the turret hatches like a rocket engine or giant blowtorch. Soviet tanks like the T55 or T72 are less spectacular, but generally pop their turret off, which may land nearby or sometimes quite far away, depending on what hit it and how much and what kind of ammo was in the gun's automatic loader.

35 posted on 12/10/2008 1:08:18 PM PST by archy (Et Thybrim multo spumantem sanguine cerno. [from Virgil's *Aeneid*.])
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To: archy

Wouldn’t the concussion bust everyone’s eardrums?


36 posted on 12/10/2008 1:12:06 PM PST by B4Ranch ( Veterans: "There is no expiration date on our oath, to protect America from all enemies, ...")
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To: archy

I have had the opportunity to inspect a couple of tanks that had burnt. The bent and twisted metal inside told me that some nasty moments had occurred inside it. I could only pray that the crew died very quickly. One of them had a lot of soil inside it as if it had rolled and slid down a hill.


37 posted on 12/10/2008 1:19:02 PM PST by B4Ranch ( Veterans: "There is no expiration date on our oath, to protect America from all enemies, ...")
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To: neverdem
troops in Iraq noticed that although EFPs (Explosively Formed Projectiles) go through metal armor, often glass laminate armor (aka glass ballistic laminate armor) will stop them. Troops reported that the EFPs would not go through the bullet proof windows, which are made of glass laminate.

The same reason the Russians in Chechnya learned to hang metal tubes filled with water along the sides of their BMP and BMD tracked personnel carriers. When these began to cut down on casualties from RPGs and roadside EFP mines, the Dukhai switched to using underbelly mines instead, sometimes stacking three or four 10-kilo TM46 or TM57 antitank mines to go off beneath a single vehicle. The .75-inch belly armor of a BMP did not offer much protection from that sort of attack, and the Russian answer was to withdraw the lighter [amphibious] tracked vehicles and use personnel carriers built from obsolete tanks instead.

Indeed, even HEAT rounds have little effect on Diesel fuel carried in vehicle tanks. Both the Soviets and Swedes capitalized on this and mounted multiple fuel and water cans alongside the tracks of their vehicles. It was a stopgap measure, but probably better than nothing.


38 posted on 12/10/2008 1:20:13 PM PST by archy (Et Thybrim multo spumantem sanguine cerno. [from Virgil's *Aeneid*.])
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To: neverdem
NOTE TO ARMY AND DEFENSE DEPARTMENT: Funds for all new weapons programs are hereby canceled. I need the money to fund my socialist agenda. Signed, Commissar Osama Obama.
39 posted on 12/10/2008 1:20:21 PM PST by RetiredArmy (I vote for freedom, liberty and the way the USA was founded. Not the way the Marxists want it.)
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To: B4Ranch
Wouldn’t the concussion bust everyone’s eardrums?

The round that hit us was noisy, but occurred outside the vehicle. Obviously, a 2-stage warhead would have been a very different matter, but the concussion was probably actually more than would have been felt inside a fully-enclosed vehicle- at the time, I thought they were trying to take out the running gear and glanced a round into the ground. My surprise later when we found the quarter-sized hole burned in on one side and out on the other was matched only by my gratitude for not having been standing closer to where those holes had been burned through.

I had a CVC/ Tanker's commo helmet on at the time, which undoubtedly helped some in reducing the effect of the concussion/blast. But I was real interested in other things going on at the time, and it's quite likely that I would not have noticed a smallish nuke going iff had it been detonated in front of us.

40 posted on 12/10/2008 1:27:22 PM PST by archy (Et Thybrim multo spumantem sanguine cerno. [from Virgil's *Aeneid*.])
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