Mystery behind Aug. 28 incident puzzles Army officials (what felled an M1A1)?

Navy Times ^ | 10-27-2003 | John Roos

[bonesmccoy]

Shortly before dawn on Aug. 28, an M1A1 Abrams tank on routine patrol in Baghdad

[Poohbah]

Meanwhile, at Intergalactic Star Patrol Headquarters, somewhere near Arcturus:

"So what happened to that effort to explore out toward the edge of the galaxy?"

"Well...ah...Zontar said something about knowing a shortcut, and it looks like he made a teensy-weensy navigational error..."

[Elsie]

Dammit McCoy!

I TOLD you to set that phaser to STUN!

[SLB]

One hell of a good shot.

That is it in a nutshell. All of the conspiracy theorists need to spend a little time at Picatinny Arsenal and other locations and see for themselves exactly what the capabilities of some of the modern AT weapons are. We have come a long way baby. Even the explosive material used in the warheads has been greatly improved over the past 30 years from Vietnam era RPG's to what is on the battlefield today.

[oh8eleven]

Could a hyper-velocity rail-gun initiated depleted uranium round cause this kind of damage?
Probably not, but Hillary's stare could.

[IncPen]

ping

[demlosers]

Well it didn't penatrate through the frontal armor.

[BCR #226]

That is not damage from a particle beam. That is a projectile penetration. Whatever it was was shot with a very high velocity. The burn mark on the outer hull suggests possibly a light charge in the warhead but I've seen .308 incendiary ammunition make scorch marks that size.

I'd be very interested to know what if any parts of the projectile they recovered. In the article, they describe a yellow metal. Most yellow metals are very soft. The main exception is the slightly tinged titanium. It would be light and capable of withstanding very high velocity but usually, it's too brittle for such an application.

My guess would be some sort of tungsten steel dart with copper or brass drive bands. Make it thin enough and crank up the velocity enough and you might get such damage. For that kind of penetration and with the minor deflection the projectile had, I'd guess a MV of 5500+ fps. at least.

All of this is just guesses with the little bit of information available. I'd be able to make a better diagnosis if I could actually see the damage first hand and not in pictures.

Mike

[blackdog]

But jeeze, what round of any type can stay in tact travelling thru all that steel? It should have become molten and splattered the inside of that tank like a spraycan of Krylon torn open. Instead, that round stayed in tact and on a straight path after passing thru the steel. Whatever the round is made of, it's mighty hard and usually hard things shatter, not keep right on going like a plasma cutting eneregizer bunny.

[Cannoneer No. 4]

November 5, 2003: The "Mystery Projectile" that caused the penetration of an M-1 tanks side armor was probably a Russian RPG-7V or similar type light anti-tank rocket with a HEAT warhead. What caused the damage appeared to be an improved version with wave shaper in the HEAT warhead. The pictures (see here) of the penetration show classic HEAT warhead circular flash and light material splash (aluminum or similar from outer warhead casing) in a roughly circular area and at between 500 - 800 mm radius around the penetration hole. It also seems as if the entry hole on the skirt plate has a ragged and enlarged hole. This is consistent with wave shaped warheads that do not have optimal performance at point of impact as the jet is still being focused. In pictures 2-5 there is virtually no spalling around the inside exit hole and immediately adjacent interior equipment. Only items directly in penetration path has been punctured or splashed with molten copper (see gun guard picture). It appears as if the jet was disrupted and started deflagrating by interior components spaced effect and material compositions. The last picture shows residual heat discoloration on the switch box, which is typical of molten metal heat transfer and short-circuit effects as can be expected when you send conductive liquid or particles into an electrical box.

The damage done is similar in appearance to that done to other armored vehicles that have been penetrated by an RPG-7. In this case, the round hit one of the few areas on the side of the tank that was vulnerable to penetration by an RPG round. Russia has continually improved the RPG-7 warheads over the last 40 years, and has sold the improved warheads to any who were willing to pay for them.

[Pan_Yans Wife]

ping

[Cannoneer No. 4]

This is off topic, but I just saw this on strategypage.com:

ARMORED WARFARE: Nanotech Armor Tested in Iraq

November 18, 2003: Combat zones are great places to test new technologies, especially if these experimental items will save lives. One example is a lightweight armored turret for Humvee vehicles in Iraq. Because of its light weight construction, you cannot put a turret on a Humvee that weighs more than 400 pounds. Armor, even Kevlar fiber armor, can only provide so much protection within the 400 pound limit. But an experimental (meaning very expensive to manufacture) nanotech armor was used to construct a 200 pound armor turret that can stop 12.7mm (.50 caliber) bullets. The fiber uses nanotecholgy (where magnetism or other forces create customized molecules with special properties.) The nanofiber in the Humvee turrets looks like fiberboard, but it is 17 times stronger than Kevlar (which is itself six times stronger than steel). However, it's going to be several years before the cost of the new fiber gets anywhere near Kevlar's levels (about $50 per square yard of fiber). The experimental turrets are being used to see how the material stands up to field conditions (heat, cold, moisture, vibration and so on.) Most Humvees in Iraq are not getting shot at, much less hit, and the Iraqi gunners are not using any heavy machine-guns (like 12.7mm.) But it's easier to test how bullet proof the stuff is on a rifle range, than it is to see what kind of damage day-to-day use in a combat zone will do.

[blackdog]

It also may be that cost cutting measures and the "Commercial off the shelf" procurement methods touted by the Clintons gave a "wink and nod" toward going off spec and using mild steel in the hull sections instead of hardened tool steel. There is a hugh difference.

Worth consideration. There was a real push under the Clinton ers procurement piss-ants to dump mil-spec requirements and their burdensome costs. They even gave it an acronym. "COTS" - for commercial, off the shelf........

[fourdeuce82d]

A HEAT round burns its way through the metal...the problem is that no Stream of molten metal would maintain coherence, blast through the interior components and bury itself 2 inches into the far armor

Wrong, Wong.

from a post way back in time on Usenet-

There is a great deal of confusion concerning the "Hows" and the "Whys" of armor penetration, particularly with respect to shaped charges. The reader is therefore referred to the two best works on the subject:

Giorgio Ferrari. "The Hows and Whys of Armor Penetration" Military Technology, October 1988, p. 81-96. (Simply the best short summary you'll ever find of how both shaped charges and KE penetrators work their magic.)

Garret Birkhoff, et al. "Explosives With Lined Cavities". Journal of Applied Physics. June 1948, p. 563-582. (The "original" treatise on shaped charges. The first half qualitative and easily understood; the second half gives you an outstanding theoretical basis for understanding the math behind these damn things.)

Having said that, I will correct a basic misperception stated earlier and endlessly propagated - the liner in a shaped charge does *not* melt! Ferrari sums it up best:

"The kinetic energy imparted to the liner's metal (by the explosive wave- front) is greater by several orders of magnitude than the level required to to totally deform it. A body which has been charged with enough energy as to disintegrate itself is virtually no longer coherent, and will behave like an incoherent body, i.e. a fluid. This suggests to many that the liner "melts". No, it does not melt, but it moves at such a high speed that it can change it's shape like a fluid, if forced to do so."

Later, Ferrari closes the book on this controversey by stating "To the contrary of what is unfortunately too often said and written, neither the jet nor the slug are "pulverised", "melted", or "vaporised"; they are quite solid, but can behave like liquids when attempts are made to interfere with their motion. Birkhoff, et al have demonstrated that with quite a conclusive experiment. Several shaped charge liners were sawn up into pieces, and these were then carefully re-assembled and kept in place. When the charges were detonated towards a deep water tank, it was regularly possible to recover the slug - subdivided into as many pieces as the liner had been cut into. This clearly shows that what is mistakenly described as "melted" is actually not even melted enough to weld its pieces back together."

Also, discovery channel showed some Sandia gnomes testing a new shaped charge warhead- the liner penetrated four or five three inch thick slabs of metal, each seperated by a couple of inches, before coming to rest sticking halfway out of the last piece of armor.

Bzzzt. No biscuit! *grin*

[Cannoneer No. 4]

archy, how 'bout add The Shrew to the Treadhead Ping List. He used to be an 1811.

The Shrew: Ping!

[Cannoneer No. 4]

archy, how 'bout add The Shrew to the Treadhead Ping List. He used to be an 1811.

The Shrew: Ping!

[R. Scott]

Every armored vehicle ever made has a weak spot. It might not be very large, but it will be there. In this case it is only a few inches wide, but a good – or lucky – shot will penetrate.
I remember how effective the B-40 and RPG – 7 was in Viet Nam. They can only be better now.

[SLB]

Every armored vehicle ever made has a weak spot. It might not be very large, but it will be there. In this case it is only a few inches wide, but a good – or lucky – shot will penetrate.

I hate to put it this way, but you are right on target.

[blanknoone]

Fair enough that melt/burn are the wrong terminology. I still cannot think of a better word for a shaped charge penetration of solids without posting a paragraph on solids behaving like liquids under shock pressures.

It also does not distract from the fact that in this case the behavior was markedly different from a shaped charge on the inside of the tank. In your example, they were shooting it into a tank of water to preserve it. Note they did not shoot it through the gunner's flak jacket, the TNB, a few other components and into the far side armor. That is the behavior of a KE penetrator, not the residual of a HEAT round.

It is very unlikely this is a simple HEAT round...something is up, and I still think the something is a combination shaped charge/KE weapon.

[.cnI redruM]

Honestly, I'm dubious as to whether the Stryker is suitable to any combat environment the Army may fight in.

[archy]

Honestly, I'm dubious as to whether the Stryker is suitable to any combat environment the Army may fight in.

It's not *supposed* to be a fighting vehicle. But I bet it ends up being one.

-archy-/-