[Mark Tyson]

October 27, 2003

‘Something’ felled an M1A1 Abrams tank in Iraq – but what?
Mystery behind Aug. 28 incident puzzles Army officials

By John Roos
Special to the Times


Shortly before dawn on Aug. 28, an M1A1 Abrams tank on routine patrol in Baghdad “was hit by something” that crippled the 69-ton behemoth.
Army officials still are puzzling over what that “something” was.

According to an unclassified Army report, the mystery projectile punched through the vehicle’s skirt and drilled a pencil-sized hole through the hull. The hole was so small that “my little finger will not go into it,” the report’s author noted.

The “something” continued into the crew compartment, where it passed through the gunner’s seatback, grazed the kidney area of the gunner’s flak jacket and finally came to rest after boring a hole 1½ to 2 inches deep in the hull on the far side of the tank.

As it passed through the interior, it hit enough critical components to knock the tank out of action. That made the tank one of only two Abrams disabled by enemy fire during the Iraq war and one of only a handful of “mobility kills” since they first rumbled onto the scene 20 years ago. The other Abrams knocked out this year in Iraq was hit by an RPG-7, a rocket-propelled grenade.

Experts believe whatever it is that knocked out the tank in August was not an RPG-7 but most likely something new — and that worries tank drivers.

Mystery and anxiety

Terry Hughes is a technical representative from Rock Island Arsenal, Ill., who examined the tank in Baghdad and wrote the report.

In the sort of excited language seldom included in official Army documents, he said, “The unit is very anxious to have this ‘SOMETHING’ identified. It seems clear that a penetrator of a yellow molten metal is what caused the damage, but what weapon fires such a round and precisely what sort of round is it? The bad guys are using something unknown and the guys facing it want very much to know what it is and how they can defend themselves.”

Nevertheless, the Abrams continues its record of providing extraordinary crew protection. The four-man crew suffered only minor injuries in the attack. The tank commander received “minor shrapnel wounds to the legs and arms and the gunner got some in his arm” as a result of the attack, according to the report.

Whatever penetrated the tank created enough heat inside the hull to activate the vehicle’s Halon firefighting gear, which probably prevented more serious injuries to the crew.

The soldiers of 2nd Battalion, 70th Armor Regiment, 1st Armor Division who were targets of the attack weren’t the only ones wondering what damaged their 69-ton tank.

Hughes also was puzzled. “Can someone tell us?” he wrote. “If not, can we get an expert on foreign munitions over here to examine this vehicle before repairs are begun? Please respond quickly.”

His report went to the office of the combat systems program manager at the U.S. Army Tank-automotive and Armaments Command in Warren, Mich. A command spokesman said he could provide no information about the incident.

“The information is sensitive,” he said. “It looks like [members of the program manager’s office] are not going to release any information right now.”

While it’s impossible to determine what caused the damage without actually examining the tank, some conclusions can be drawn from photos that accompanied the incident report. Those photos show a pencil-size penetration hole through the tank body, but very little sign of the distinctive damage — called spalling — that typically occurs on the inside surface after a hollow- or shaped-charge warhead from an anti-tank weapon burns its way through armor.

Spalling results when an armor penetrator pushes a stream of molten metal ahead of it as it bores through an armored vehicle’s protective skin.

“It’s a real strange impact,” said a source who has worked both as a tank designer and as an anti-tank weapons engineer. “This is a new one. … It almost definitely is a hollow-charge warhead of some sort, but probably not an RPG-7” anti-tank rocket-propelled grenade.

The well-known RPG-7 has been the scourge of lightly armored vehicles since its introduction more than 40 years ago. Its hollow-charge warhead easily could punch through an M1’s skirt and the relatively thin armor of its armpit joint, the area above the tracks and beneath the deck on which the turret sits, just where the mystery round hit the tank.

An RPG-7 can penetrate about 12 inches of steel — a thickness far greater than the armor that was penetrated on the tank in Baghdad. But the limited spalling evident in the photos accompanying the incident report all but rules out the RPG-7 as the culprit, experts say.

Limited spalling is a telltale characteristic of Western-manufactured weapons designed to defeat armor with a cohesive jet stream of molten metal. In contrast, RPG-7s typically produce a fragmented jet spray.

The incident is so sensitive that most experts in the field would talk only on the condition that they not be identified.

One armor expert at Fort Knox, Ky., suggested the tank may have been hit by an updated RPG. About 15 years ago, Russian scientists created tandem-warhead anti-tank-grenades designed to defeat reactive armor. The new round, a PG-7VR, can be fired from an RPG-7V launcher and might have left the unusual signature on the tank.

In addition, the Russians have developed an improved weapon, the RPG-22. These and perhaps even newer variants have been used against American forces in Afghanistan. It is believed U.S. troops seized some that have been returned to the United States for testing, but scant details about their effects and “fingerprints” are available.

Still another possibility is a retrofitted warhead for the RPG system being developed by a Swiss manufacturer.

At this time, it appears most likely that an RPG-22 or some other improved variant of the Russian-designed weapon damaged the M1 tank, sources concluded. The damage certainly was caused by some sort of shaped-charge or hollow-charge warhead, and the cohesive nature of the destructive jet suggests a more effective weapon than a fragmented-jet RPG-7.

A spokesman for General Dynamics Land Systems, which manufactures the Abrams, said company engineers agree some type of RPG probably caused the damage. After checking with them, the spokesman delivered the manufacturer’s verdict: The tank was hit by “a ‘golden’ RPG” — an extremely lucky shot.

In the end, a civilian weapons expert said, “I hope it was a lucky shot and we are not part of someone’s test program. Being a live target is no fun.”

John Roos is editor of Armed Forces Journal, which is owned by Army Times Publishing Co.

[Sunray]

Geezuz, you can hear the pucker factor rising from here. The only place a weapon capable of defeating the armour on an Abrams is the West. The Eastern Bloc, aside from being gone, is too disorganised and broke to develope anything.

[Leatherneck]

Would that it were so, Sunray...but that's not so. Any number of shaped-charge warheads can defeat an Abrams with a well-placed (or lucky) shot. Penetrating the skirt is not that difficult. Sounds like an improved or large-diameter shaped charge to me.

TC
TFL Survivor

[OEF_VET]

Yeah, I saw this in The Army Times. As scary as it may be, it's still better to be wearing an Abrams instead of only a DCU top, IBA and Kevlar.

I talked to some friends at Ft. Campbell yesterday, one back for R&R and another back to ETS. Both said it was pretty crazy over there. The guy back for R&R said he is getting recommended for a Bronze Star. He's currently assigned to the protection detail for the 101st Division Artillery Commander and CSM. Apparently they got hit by an ambush in Mosul, which is according to him, a near daily event. Luckily, I can report that no one in my former BN has been killed. Thank God! There have been a few WIA's, but no KIA's. Hopefully they'll get through the entire year with no fatalities.

Frank

[cracked butt]

It seems clear that a penetrator of a yellow molten metal is what caused the damage, but what weapon fires such a round and precisely what sort of round is it?

Golden BB?

[Navy joe]

I dunno, I'm not the expert that's puzzled, but that sure screams "Milan" to me.

[Keith]

It was one of dem Cop-Killer bullets...

Keith

[George Hill]

Navy Joe beat me to it... A Milan. Usually launched from vehicles, but there are infantry variants, and they have a much larger charge than an RPG.
This isn't that big of a threat, these missiles are few, and they are outdated. Big bang, yeah... but let's put it this way:
Our DRAGON ATGM was better.

[mtnbkr]

I dunno, I'm not the expert that's puzzled, but that sure screams "Milan" to me

I'm a bit dense here, but what's "Milan"?

Chris

[tex_n_cal]

A .475 Linebaugh? :evil:

[Mike Irwin]

"yellow molten metal"

Very simple...

Camel piss.

That will take out just about anything.

[cordex]

I think Keith is right.
I read on the innernet that teflon coated black-rhino-talon-murder-death-kill bullets can do this.
TV said so too.

[Mk VII]

see MILAN missile at http://www.army-technology.com/projects/milan/index.html#milan3

[mete]

The shaped charge is nothing new, it was introduced in the early 1900s .The Limpet mine , bazooka, the navy's Rockeye bomblet, are just some of the weapons that use the idea. The Rockeye was used to some extent in Vietnam but was the ideal air drop anti-armor used in Desert Storm.

[Teufelhunden]

Penetrating the skirt is not that difficult. Sounds like an improved or large-diameter shaped charge to me.

Dunno about that wardog...a shaped charge's effectiveness is very dependant on getting the charge to detonate at the right distance from the barrier you wish to penetrate so that the full power of the Monroe effect is applied to that barrier.

One of the functions of tank skirts and other types of armor that have a void between them and the main hull are to make the shaped charge detonate prematurely so that the worst of the blast is overfocused and does not penetrate the hull.

Having said that, it wouldn't be impossible for someone to design a shaped charge that is SUPPOSED to detonate at the skirt and be focused for the distance between the skirt and the hull--anyone with access to a Jane's guide could probably figure out what that dimension is...

-Teuf

[gun-fucious]

Galactic Continuum Patrol reports nothing to see here, move along citizens
Please ignore the man with the particle beam weapon,
or we will turn you into a pillar of salt.

[cordex]

it wouldn't be impossible for someone to design a shaped charge that is SUPPOSED to detonate at the skirt and be focused for the distance between the skirt and the hull
Focus through the skirt? I could be wrong, but this doesn't sound possible. An explosion focused on the hull would be diffused by the skirt, I think.

This sounds like a very cohesive and precise penetration, very unlike standard hollow charges. Keep in mind, the report says that it penetrated the skirt, the hull, through the tank and then into the far hull. Hmm ... depending on the angle, that could be around 8 feet of penetration (through composite armor, empty space and various materials). That's not the behavior of typical hollow charge devices, is it?

[Nando Aqui]

Even though this is not what was used in this instance, I had never stopped to read about the RPG-7's :eek: I am impressed!

RPG-7: http://www.g2mil.com/RPG.htm

Actually, depressed, :( since my son is a UH-60 Black Hawk pilot.

Alex

[Mike Irwin]

Cordex,

aren't there 2-stage munitions that are designed to do that?

[cordex]

aren't there 2-stage munitions that are designed to do that?
I was under the impression that 2 stage munitions were designed to defeat reactive armour rather than "skirted" armor (or whatever the technical term). The first charge would set off and destroy the section of explosive armor (and be defeated thereby) while the second charge would hit the hull itself.

Don't know how that plays with armor standoffs.

[Dave R]

Prolly just some reloading nut trying a .22/.50BMG wildcat.

[Matt G]

A good handload?

http://www.gunaccessories.com/Speer/African%20GrandSlamRifleBullets.asp

:)


Distinctive print of a shaped charge was not present.

[Mike Irwin]

Hum...

Now that you say that, Cordex, I think you're right.

[Camel]

Seems a little odd to me that anyone would bother to design a weapon that only makes a hole the size of a pencil. Wouldnt you have to be pretty accurate to stop something as big as a tank with a hole that small?

Correct me if Im wrong but isnt the purpose of a shaped charge to defeat the armor then cook/kill everything inside? If so it doesnt seem right that it continued to penetrate through the crew compartment and into the other side. Is it possible that a two stage warhead hit a non-reactive armor piece, the first stage defeated the armor and the second just shot right through the other side.

Although I really have no idea what Im talking about.

[Zorro]

I suspect a previously unknown Russian version of the US Copperhead round.

Would fit Russians pattern to use Brass instead of Copper in their own version.

[Sactown]

My guess is our friends the Russians sold them some of their Kornet E missles. http://www.army-technology.com/projects/kornet/

[Malone LaVeigh]

I wonder if some of the DU we shot their way is being remilled and sent back.

[chevrofreak]

.50BMG RAUFOSS round?

[cookhj]

could've been a variant of a platter charge. it would've had to have been a small diameter platter (maybe 3 or 4 inches) and a good amount of demo behind it. a shaped charge warhead could've done it as well, but there would've been a good amount of blast markings around the hole in the outter hole. however, the jet from a shaped charge blast probably wouldn't have penetrated that far into the tank, that's why i suggested some type of platter charge.

[Orthonym]

I thought Copperhead was a guided artillery projectile, with fins and wings.

[WT]

A CSM has a protective detail? ***?? Let him pack his own weapon.

[rick_reno]

Is there a link to the original source for this article? Google couldn't find it.

[Langenator]

Shaped charge warhead, such as those used on RPGs, the US AT-4, and pretty much all of the world's ATGMs, destroy tanks usually by hitting something inside the tank that will burn and/or explode. The warhead creates a stream of superhot gas and metal, about the diameter of a pencil or your pinky finger, which burns through things. If this stream hits something like the tanks fuel or ammuntion, that something catches fire and maybe explodes, killing the tank. It can also hit the engine, causing that to burn, disabling the tank and possibly causing the fuel tank to blow.

The M1 is well compartmentalized-fire in the engine won't get to the crew compartment, and the ammo stowage is designed so any explosion is directed up and away from the crew, and, as noted in the article, has a very effective fire suppression system. This tank will probably be repaired and back in the fight once the techies finish examining it to determine what penetrated it.

I'm somewhat skeptical of the shaped charge though, because the Chobham composite armor used on the M1 is supposed to be extremely effective-much more so than steel-at defeating shaped charge warhead. Something about ceramics and composites that disperse the thermal energy. Maybe some sort of self-forging-fragment warhead.

[Ed]

Copperhead is a fin guided artillery round. Well, Actually Laser guided, fin stabelized. Don't think they are firing to much Arty over there now. BG's that is. Basicly if I read this right, It sounds like it could be a version of a sabot round designed to be sholder fired. Hmmmm. An updated AT-4 even. With lower velocity than a tank round which would explain the minor injuries. Very interesting. Then again it could be the new S&W .50 assault revolver with gold bullets.

[OEF_VET]

rick_reno, here is a link to the story, as published in The Army Times:

Pencil thin, but able to stop a tank. (http://www.armytimes.com/story.php?f=0-ARMYPAPER-2334405.php)

WT,

Yeah, the CSM carries his own weapon, but you wouldn't expect him to walk around by himself would you? As the DivArty CSM, it's his job to take care of all the enlisted soldiers in the 101st DivArty. That requires him to do a lot of driving around. By Army policy, there has to be a MINIMUM of two vehicles to go anywhere. It's probably three or four given the situation on the ground in Iraq. There has to be someone else in those other vehicles. It just so happens SPC Zinger is a SAW gunner assigned to that detail.

As for the Copperhead, it is an artillery-delivered, guided munition, fired from 155mm howitzers and guided to its' target by a Forward Observer with balls of steel, using an AN/TVQ-2 G/VLLD. (Ground / Vehicular Laser Locater Designator) The range for both the Copperhead and the G/VLLD are classified, although the Army will say that the Copperhead is effective to a range in excess of 12 miles. This wasn't a Copperhead though, as the Copperhead would have made a much larger hole and the firing of an artillery piece by any Iraqis would have brought forth such vengence from the American Army, that it would have been impossible to keep it off the news wires.

Frank

[Blackhawk 6]

Based on what I have read, it appears that A consensus is forming that the weapon responsible was an RPG-7VL.

[RustyHammer]

Aliens ..

[50 Shooter]

Ooops, I think I might have done it. I was out shooting the other day and just happend to be shooting some SLAP rounds. You know how a .50BMG can take out a satellite, guess I had a flier and now the .50 BMG can be credited with taking out an Abrams.

[gun-fucious]

dust devils
or mayhaps Enkidu's revenge (http://www.4reference.net/encyclopedias/wikipedia/Epic_of_Gilgamesh.html)

[Marko Kloos]

The damage described is similar to the terminal effects of a German-French MILAN anti-tank missile. The Russians copied the MILAN for one of their own ATGM designs; maybe the bad guys have a stash of those "Milanski" around.

[KC]

There are pictures of this over at the Strategy Page (http://www.strategypage.com/gallery/default.asp?target=missile_mystery.htm)

[buzz_knox]

Based on what I have read, it appears that A consensus is forming that the weapon responsible was an RPG-7VL.

According to the article, "[e]xperts believe that whatever knocked out the tank in August was not an RPG-7, but most likely something new — and that worries tank drivers."

While an RPG could penetrate the area under the skirt, the plasma jet wouldn't have acted like that. The jets tend to break up when exposed to air spaces after formation, which is one of the reasons for spaced armor. Here, the round penetrated and then stayed together, with sufficient energy to penetrate both sides of the safety guard around the breach and punch into the opposing side of the hull.

[cordex]

Marko,
I'm inclined to defer to you on this, as you've had far more experience in this area than I, but ...
Did you look at those images? A Milan missile will do that?

[Sean Smith]

Penetrating the side armor of an M1 through the skirts isn't very impressive... the heavy-duty armor is in the hull front and the turret front & sides. I'm sure lots of conventional, widely available weapons out there could penetrate an M1 on a side shot. The M1-series were only ever nigh-invulnerable in the frontal hull and turret arcs. That's by design, otherwise the thing would weigh at least 100 tons.

The front armor skirts are classified armor packages, but the rear skirts are just steel IIRC. In either case, the thickness of the armor on the sides (even if it is a Chobham-esque side bit that takes the hit) isn't thick enough to make it 100% proof vs. all current anti-tank warheads.

Bottom line is, the article is non-news.

[Ironbarr]

but -MILAN is a portable medium range, anti-tank weapon manufactured by Euromissile, based in Fontenay-aux-Roses in France.I wonder when it (these - they) were delivered to the culprit(s).

And I see that the German military (among others) have a mess of these things.

Keep your friends close - and your enemies closer. I wonder who's who.

-Andy

[Langenator]

I wonder when it (these - they) were delivered to the culprit(s).

IIRC, the KGB stole the design and the Soviets built their own version. Not sure if that was the (Soviet) AT-4 ATGM or the AT-7. The latest version ofthe AT-7, the AT-13, also features a tandem charge warhead.

[blades67]

MILAN 3, armed with a tandem warhead with a new firing post with jam-resistant pulsed-beacon infrared guidance, has been in production since 1996 and has been ordered by France, Cyprus and two other armies.


My bet is that if it was a MILAN, it came through Cyprus.:scrutiny:

[buzz_knox]

A Milan 3 might do it, except for the fact that tandem warheads are shaped charges, and shaped charges don't tend to act this way. This looks to have been a solid tungsten penetrator (not DU as DU tends to ignite).

[Orthonym]

Might there be a single-minded, obsessive wildcat-cartridge-developer-with-a-really-good-machine-shop over there in Iraq somewhere, the same kind of romantic bad*ss all of us here imagine ourselves to be?

[Dilettante]

Good enough to machine tungsten??
What kind of equipment is needed for that?
Where are they getting tungsten from, anyway?

Doesn't sound like the work of a single romantic, unless they have access to the old government's weapons caches anyway.

[sch40]

An RPG-7 can penetrate about 12 inches of steel impressive.

Anyone here know how far into steel a good multipurpose Raufoss round will penetrate? :evil:

[Zorro]

NOT so impressive!

A VERY narrow penetration by a VERY small penetrator.

GOLDEN BB.

High or low and it would have just have been a nuisance.

I probably was a French Weapon.

;)

[T.Stahl]

The following is taken from an article in the November issue of the German military journal "Soldat und Technik" (Soldier and Technolgy), titled "Panzereinsätze im zweiten Golf-Krieg" (Operations of Armoured Units during the second Gulf-War).

"The different reports show differing accounts of losses; according to them the losses among armoured vehicles total:
- twelve M1A1 Abrams (8 x US Army, 4 x USMC)
- one M113A1
- one M109A6 Paladin
- one M9
- four AAV-7
- one Challenger 2
- one Scimitar

Additional information about the individual cases:
One M1 was hit by an Hellfire, fired from an AH-1W. One M1 fell from a Bridge in Bagdad after the driver was killed by a sniper. All of the remaining M1s were hit by RPG-7 and RPG-16; the Iraqis fired at the less protected M1's rear. Due to the relatively low ignition temperature (flaming point?) of the cerosene (JP-4?) almost all vehicles caught fire and burned out. ... It's remarkable that according to theses reports no loss happened to due mines. The picture an destroyed M1 ("Cojone EH") next to a mine crater was sometimes interpreted as a mine damage - actually this vehicle is said to have been destroyed by an Iraqi RPG-7. To keep the tank from falling into Iraqi hands, it was bombed by the USAF and later salvaged by allied units.
A total of 151 M1s have been fired at, including the ATGN AT-14 "Kornet"; Syria delivered about twelve launchers and 200 missiles in 2003. The loss of the Challenger 2 was caused by friendly-fire from another Challenger in the vicinity of the Shatt-al-Basra channel. The Scimitar was hit during daytime by an A-10. ..."

[Azrael256]

There is obviously a whole lot we don't know here. It had to be a solid projectile, otherwise it wouldn't have gone through the airspace inside the tank, and it likely wasn't DU, so the tungsten idea is good. Shaped charge penetrators are generally made with very soft metals, like copper, so there would be a good deal of copper splattered around, which would be easy to find. Also, a shaped charge, being hot enough to melt the metal, leaves a rather distinct pattern in the remaining metal as it recrystallizes. Not distinct from each other, but distinct from a kinetic penetrator, or a pyrokinetic like DU. DU also would have left particles EVERYWHERE. At the very least, I can guarantee that we know just exactly what it was made of. Everything leaves fragments, and those fragments can be easily identified by a skilled metallurgist. Once we know what the penetrator's makeup was, we can begin to identify it.

The main problem with punching holes in tanks is that you need a great deal of energy to do it. If you've ever seen the actual size of the APFSDS-T penetrator, you'll be amazed that something so small can be pushed so fast. So something had to fire this kinetic penetrator (assuming that we're actually getting the information that I think we are and it isn't a shaped-charge) REALLY fast. That something is likely relatively large. This isn't some hoss AK round.

So, it's either that, or somebody used a really neato laser gun, which, while unlikely, is a really cool thing to think about.

[seeker_two]

Maybe some Al-Qaeda reloader that's been experimenting w/ RPG warheads, perhaps?

Wouldn't put it past them. It's not like they're worried about their own personal safety or anything...:rolleyes:

[blacksuit]

I was scimming through past post and came upon this. I was in the 2/70th AR battalion about 3 years ago and boy I am glad to have missed that. Luckily I got out before the ???? hit the fan. But let me one to say the M1A1 is one bad mother.... Shawn

[MrMurphy]

A Milan would have sucked the crew out the exit hole. Several Milans killed various tanks in Bosnia and the crew did not survive.

A Milan is a full size antitank missile, not a shoulder launched "Hope like hell it works" RPG. If a Milan, TOW, or HOT missile had hit there on the M1A1, it most likely would have been a catastrophic kill. No more Abrams.


Most likely, either a penetrator light cannon round, or a upgraded RPG round.

[Ryan1021]

This is what happens when you let the AWB sunset. These weapons are going to be here anyday now. :D

[extremefishin00]

Maybe someone happened to get hold of the plans for Steyr's AMR (Anti-Material Rifle) and built their own? It does use a 5.5mm flechette made out of tungsten, and a muzzle velocity around 4,700 ft/sec.


Steyr AMR (http://world.guns.ru/sniper/sn46-e.htm)

[twoblink]

Rail Gun.

[RevDisk]

I doubt it was specifically a APFSDS.


I've worked with anti-tank weapons before. Whatever killed that Abrams wasn't a missile based weapon. At least, not an RPG, MILAN, Javelin, or other conventional missile/rocket weapon. I saw the effects of most of them on Serbian tanks. Most conventional anti-tank missiles/rocket weapons used some variant of the shaped charge.

I'd say a electromagnetic launched projectile, really odd tungsen-composite penetrator, or a plasma/laser weapon. I've seen missile-delivered plasma weapons (missile explodes before reaching target, heats the copper to plasma state), and it sure as heck was more crude than whatever took this tank out.

Electromagnetic weapons (rail guns) are still big toys. You need very big, expensive capacitors. To make one smaller than an RV, you'd need a lot of cash to buy expensive electronics.

Exotic penetrators would be the low-tech opinion. Someone somehow custom designing their own penetrator, put it in a sabot, and launching it at extremely extremely high velocity.

Plasma and laser weapons tend to be crude. This ain't Star Trek. The most advanced plasma state weapon I know is our TOW missile that basically superheats copper to plasma state by explosive charge. I know we were toying around with laser systems mounted on a Boeing 747 to shoot down ICBM's.


My guess, and it's really just a guess... Some country wanted to test out their new classified weapon system on the most advanced tank on the planet. It obviously worked extremely well. That worries me, that there might be more of these damn things out there.


(Note to self, whenever talking to a foreign military using T-34's, never never say "Cool! I never saw one of these before that wasn't burning." )

[meche]

I don't have any opinion on what did this, but I recall seeing speculation on another board that this was friendly fire/negligent discharge from a Bradley (25mm AP round?).

http://www.globalsecurity.org/military/systems/ground/m2.htm

Something to think about.

[RevDisk]

25mm "Bushmaster" chaingun won't go through the side armour of a Abrams.