Posted on 11/18/2003 2:35:56 PM PST by fourscore
http://www.sciscoop.com/story/2003/11/3/171841/084
The M1A1 Abrams tank is widely acknowledged to be the best tank in the world. It weighs just shy of 70 tons and much of that weight is armor to protect the vehicle and its crew. There are two main threats against a tank: HEAT (High Explosive Anti-Tank) rounds and KE (Kinetic Energy) rounds. To greatly oversimplify, HEAT rounds produce a blob of super-hot molten metal that cuts through armor like a torch; KE rounds have long, slender dart-like projectiles that punch through armor like a bullet. The structural armor of the tank is designed to stop KE rounds and is based on the so-called "Chobham armor" technology developed by the British. This is basically a sandwich of steel and depleated uranium plates, ceramics, and plastic composite honeycomb. When hit by a anti-tank KE projectile, the ceramic and composite components vaporize so violently they actually push an incoming dart back out the way it came in before it is able to fully penetrate the armor plating. Attached to the outside of the M1A1 is a second type of armor called reactive armor, basically boxes of steel plated explosives that are intended to disrupt the molten plasma jets created by HEAT rounds before they can get to the vulnerable structural armor. Obviously the offense-defense aspects of protecting and penetrating tank armor have been given a great deal of thought by the U.S. military and has resulted in the M1A1 having a virtually perfect record as being unstoppable in combat. That is, until last August 28. On that date, something disabled an M1A1 tank in Baghdad, and the U.S. Army is still trying to figure out what it was.
As reported in Army Times: The incident is so sensitive that most experts in the field would talk only on the condition that they not be identified. 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.
"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."
"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.
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."
You'd have to divert most of the Iraqi electrical grid's capacity to charge the capacitors in any reasonable amount of time.
Next?
or it was AT-14 Kornet!
Chunks of shattered armor roughly equivalent to the the size of golfball to that of an orange or softball, as developed by impact from a HESH or HEP round would be *a lot* and could be expected to kill everyone inside, destroy optics, hydraulic lines, batteries and radios, and probably ignite the ammunition aboard [though not usualy detonate it until the fires touch off a HEAT or HE round's detonator and booster charge] A *little* evident spalling would be about equivalent to the result of hitting a glass marble with a sledge hammer. But flying through the interior of a tank at speeds in excess of a mile per second that too can do serious damage- as seen in the impacted Abrams interior- if not to as severe a degree.
HESH/HEP is particularly effective against reinforced concrete, less so against spaced *Chobham* armor found used in the construction of British and US tanks. Typically, a HESH round impact may not even penetrate the armor, just chip off enough scabs from the interior surface to get the job done. Think of the demonstration of inertia when a cue ball strikes a line of pool balls and the last one on the end flies off with nearly the velocity of the cueball hitting the stack. Seperate the balls a bit, and that won't happen.
If you've ever seen a tempered glass window struck by a BB or air rifle pellet that results in a cone-shaped hole on the inside of the window and a tiny hole that may not even be large enough to allow the passage of the BB through it, you've got an idea of how well it can work
Not.
A Tonka toy is better on paper, but until you get your tank on the battlefield, then the M1A1 Abrams is the best tank. :)
Squash head projectiles had a soft explosive that on impact squished out into a platter shape before detonation, the shock wave travels through the armor and knocks a flake loose on the other side.
As I remember.....
You're exactly correct: known as HEP [High Explosive, Plastic] in US practice, HESH [High Explosive Squash-Head] to the Brits. The 76mm gun of the Saladin armored car was particularly effective with a HESH loading, developed in the days before spaced/Chobham armor was on the scene. Once it showed up, the Saladin was pretty much withdrawn from any frontline service.
But the energy from such an impact and explosion also transmits heat, as well as the friction of the *fleeks* of metal [love the term; gotta remember that one!] tearing themselves away from the interior surface combine to get the resulting sand-like chips hot enough to ignite fuel, hydraulic fluid. ammunition propellent or flesh. And remember that whatever pierced the Abrams was hot enough to set off the Halon fire extinguishers....
That could have been a HEAT round's Monroe effect jet, a self-forged beryllium/copper projectile from a Miznay-Schardin effect self-forged projectile...or maybe, spall from a HESH riund or a HVAPFSDS sabot penetrator.
Not.
So what is the best in your opinion and why?
Then you must mean maximum range....
If it was an RPG projectile, I doubt it was the usual PG-7VL shaped charge grenade. The Abrams has faced them for years, they're a known quantity, and the tankers involved can be reasonably expected to have been very familiar with the effects of the RPG rounds on tanks.
The improved PG-7VR dual-charge rocket used for first detonating reactive armor, then driving the second charge's blast through the armor is possible, especially if the first charge had been disabled or combined with the second, as unneeded since no reactive armor was present of the Abrams.
And there's another, real scary possibility: what if someone has taken the principle of the hypervelocity LOSAT round and applied it to an unguided HVAP kinetic energy round for the RPG7 launcher. Especially if used to drive a saboted penetrator, such a round could be really bad news for Abrams tankers.
-archy-/-
Not.
So what is the best in your opinion and why?
The M1A2 SEP certainly comes to mind. So does the Merkava Mark 4
But if you look at the location of the hit (center mass), that is indicative of a stand off shot. Operators are trained to aim for center mass. A close in shot from an RPG would probably go for a mobility kill (take out the engine, or rear sprocket) instead of going for the well protected crew compartment.
The firm that closely follows armor development recently said that the latest German Leopard was the best tank in the world at the training course- but that the Abrams was superior in battle.
Which would you rahter have?
They used to do it by hand in the old days, lost lots of hands that way, now they put one of these on a long pole and shoot a hole in.
No, minimum range. ATGMs, particularly SACLOS (semiautomatic command line-of-sight) ones, require a MINIMUM distance from firing until the missile is "captured" by the gunner's sight and actually starts guiding on the target. Too close, and any hit is just plain dumb luck.
1. Just because you WANT to hit a certain point doesn't mean you actually WILL hit that point.
2. Like I said, there wasn't 400 meters available for missile run-out.
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