That will be a neat trick, because if the second stage resembles the first stage it will be as aerodynamic as a can of butter cookies.
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.
“of course it only needs to work once.”
Until somebody comes up with a two stage EFP...
We need to remain “The baddest on the block”.
Excuse me
ladies, but that way no one will “mess” with us.
I’m thinking the antitank weapon of the future will be something like the A-10 gatling gun. Fire a stream of depleted uranium bullets at the exact same spot, each one weakening the armor a little more, until they start penetrating.
The A-10 is a Bad Ass. What ever works and is most effective to make our enemies take notice and think twice.
My guess is the newest vehicles will have a high-velocity rail type gun or a Very High Powered Laser.
Some of the new lasers can punch a hole through 4” of steel in under 4 seconds.
I can also vision laser defensive weapons for long/short range naval vessel point defense, like the air borne laser instead of the little R2 gattlings. They could be powered by the vessels nuclear reactors instead of chemical batteries.
at that point we’ll see the end of armored vehicles. You won’t be able to make armor thick enough, so no point in having it at all.
You’ll still have to protect from the anti-tank gun, RPG’s, regular rifles, and .50 M2’s so armor isn’t going to go away.
> Fire a stream of depleted uranium bullets
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?
That will be a neat trick, because if the second stage resembles the first stage it will be as aerodynamic as a can of butter cookies.
IIRC, the missile system they encountered was the AT-3 "Sagger".
It’s super dense.
> It’s super dense.
Ahhh. That makes sense, then: it would pack a heavier punch than lead, size-for-size and all things like velocity being equal.
Thanks for the explanation.
It's very dense as in mass per volume. At 19 g/cm3 uranium’s density is similar to that of gold or tungsten, and nearly twice that of lead. IIRC, that's about 19 times the density of water.
You’re not far off with the “glow in the dark” remark. Aside from being super-dense, depleted uranium is a pyrophoric metal, which (if I understand the process correctly) can add an incendiary effect when a d-u round penetrates the target’s armor.
(Chemistry majors and tank commanders feel free to correct me here if I’m incorrect in my description :-) )
Fascinating read — thanks!
So it can catch fire, sorta like magnesium?
(Tee-hee-hee! Gotta love it!)
DU is super-dense!
Not necessarily. Remember, if the focused fusion devices work out, it won’t matter how big the tank is. You’ll be able to move something that’s the size of building, perhaps even on an air cushion a la David Drake.
Also, I don’t see energy weapons going man portable any time soon.(Not unless someone manages to make David Drake’s “powergun” real, and that’s probably never going to happen - the more so since *he* doesn’t believe it’s possible and specifically states that they’re only there so he can tell stories.) What I do see is tanks adopting more and more active defenses: Multispectral smoke from smoke projectors, already in use, scatters and diffuses lasers to the point where they are harmless to most armors. Active point defenses, like the Israeli Arrow system, can knock down incoming RPGs, guided missiles, and even deflect incoming recoilless rounds. The Russian “Arena” system can supplement this, plus take out anything that gets into your dead zone around the tank.
On top of which, depleted uranium is a very *hard* metal, so it makes a dandy penetrator.
Something interesting
Ping.
bttt
Tandem warheads. Its already been done, including by the Russians.
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.
ping
ping
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.
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.
Not at all. Ever hear of mirrors?
Nasty stuff.
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!
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.
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.
Wouldn’t the concussion bust everyone’s eardrums?
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.
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.
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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.
> 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.
Wow! Thanks for the explanation. There would be alot of civilians out there that believe the US fires depleted uranium at the enemy just to be extra-nasty and pollute them with nuclear waste. It would never occur to them that DU is actually ideal for piercing the enemy’s armor.
Cheers for that!
*DieHard*
The term used by the boffins for the effect you describe is ablating, chipping away bits of the armour a chunk at a time, hopefully at a high rate of fire.
During the late 1960s our tank battalion was equipped with four M114 recon tracks that were amphibious, unlike the M48 and M60 tanks of the period. Though there was no AT weapon fitted on the M114, a power turret was developed for the M114, allowing its .50 caliber machinegun to be aimed using optical sights and with power traverse and elevation. This was known as the M114A1, which suffered from having an ammo supply of only 105 rounds for the .50. The "improved" version was the M114A1E1, which mounted a 20mm automatic cannon, which meant that it could give a good account of itself in an encounter with a bad guy armoured car or light tracked vehicle. Unfortunately, the M139 autocannons suffered from feed problems that were never worked out, and the vehicles in our outfit had plain old .50 M2 Brownings fitted. There's not much wrong with that.
Except that our tanks then carried the M85 .50 MG, appreciated by tank crews for its quick-change barrel and switchable hi-low rate of fire suitable for giving pesky helicopters some serious problems. The only thing wasm the links for the tank gun ammo were different from those in the scout APCs, who worked alongside us. And if they shot off their ammo [which they were supposed to do first, since they were scouts hopefully screening us from and nasty surprises] they couldn't just borrow a couple of cans of ammo from us, but had to break it out of the links and rebelt it. Unhandy.
My bright-guy suggestion was to mount an M85 gun in the power mount of an M114. Come to think of it, since the mount was designed for the weight of that cannon and ammo, two M85s could be carried up there, side by side...and the M85 can be fed from either side. After a bit of tinkering, we found that a third gun could be fitted, mounted in the center forward of the other two. that meant that after the twin guns ran empty, the third could be in reserve until reloading could take place. We even came up with somne oversize ammo cans made from scrapped 5-gallon gas cans that held 225 rounds per gun instead of only 105. We submitted photos and sketches to higher headquarters, who approved the modification on a limited test basis and provided 12 extra guns for our four tracks. And they wanted us to demonstrate the modification during a firing test.
The German tank range at Grafenwohr had a number of scrapped target vehicles on it, mostly 2½-ton trucks that had been in mountain road rollovers or headons. But there was a former French M24 light tank, still complete with its fenders, tracks and main gun, though the optics and headlights had been long gone, removed or shot away.
The shoot took place at dusk. Like good little boys, the scout crews pinged short bursts out until they were bouncing tracers off the old tank hull about 400 meters out. Then they put on a nice, disciplined show of raking the tank and nearby trucks with neat 10-round bursts, totalling 20 rounds each from the twin guns. It came time to reload, and yep, they kept that center gun ready for any sudden order to resume firing. The other three scout tracks pulled up alongside the first [the engines on the beasts were Chrysler Hemis, as I recall] and they too loaded their guns up, all of them, and with the big, unofficial ammo cans we'd knocked together, 675 rounds of .50 per vehicle, 4 tracks in a row. And then they switched the guns over from the low rate of fire to high rate, from 500 shots per minute, to 1000 +. And waited for the order to let fly. They got it.
Braaaaaakkkkkkkkkkkkkkkkkkkkkkkkkkkkk
The noise was not the usual chatter of a M2 .50, much faster, and with a dozen of them going, noisy as all get out. Tracers zipped off the old tank, but the belts were only 1-in-5 tracer, the others being .50 Armour-piercing incendiary. They chewed the fenders away, cut through the track links and set fire to the rubber track pads, and tore into the turret hydraulics until the tank's main gun dropped down with a clunk. And then somebody hit one of the 5-gallon cans of water-contaminated gasoline they'd placed inside, and the thing went up like a bonfire.
In the light of the next day we got a good look at the remains of the little M24, with holes torn through- ablated- through it's turret and engine compartment.
Of course all that was back around 1967. We could do much better with some of the guns and ammo available now....
Unmanned armor vehicles will be the ‘next thing’ in my view.
A description from an old style tank: The driver said the round hit the front armor, did not penetrate, and the front wall of the tank glowed cherry red for a while.
Bump!
>I was real interested in other things going on at the time,<
I can appreciate that concern.
“Glowed red” while everyone inside looked upwards and gave a quick thanks.
It has no explosive properties of its own and no, it does not glow in the dark.
LOL.
Best to you my friend.
L
No. Depleted uranium refers to uranium that has been depleted of the U-235 isotope leaving the U328 isotope. Depleted uranium is generated when enriched (in U-235) uranium is generator for nuclear reactors or weapons.
Thanks for the correction.
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