Bulletproof?

[Darth Wong]

Assuming it is super conductive, all that takes away is the ability of the DU to further sharpen its self as it penetrates, and the flesh behind wont be quite as burned.

Precisely how does the DU penetrator "sharpen itself as it penetrates?" I'll admit I'm not an expert on specialized ordnance, but I don't see how a physical impactor will sharpen itself while plunging through steel.

I always envisioned those things as corrosion-enhanced KE penetrators, due to the heated liquid jet.

You still have a quite sharp mass of DU and steel hitting a small area at mach five that doesnt reley on being hot to penetrate significant amounts of armor.

Right, but if the target plate is harder than the DU penetrator, it will still tend to mushroom and lower the shear stress. That is the big "if". Normally, hitting it with a liquid jet will make it soft, and overwhelm any surface hardness treatments. A thermally superconductive piece of armour would eliminate this effect, and remain at full hardness for the moment of impact.

[Enlightenment]

This tells us precisely dick. Is it cold-rolled? Or is it hot-rolled? Is it annealed afterwards? Or precipitation heat-treated? Or is martensitic? Is it AISI 1020? Or AISI 4340?

RHA = MIL-A-12560

[Sea Skimmer]

Assuming it is super conductive, all that takes away is the ability of the DU to further sharpen its self as it penetrates, and the flesh behind wont be quite as burned.

Precisely how does the DU penetrator "sharpen itself as it penetrates?" I'll admit I'm not an expert on specialized ordnance, but I don't see how a physical impactor will sharpen itself while plunging through steel.

I always envisioned those things as corrosion-enhanced KE penetrators, due to the heated liquid jet.

You still have a quite sharp mass of DU and steel hitting a small area at mach five that doesnt reley on being hot to penetrate significant amounts of armor.

Right, but if the target plate is harder than the DU penetrator, it will still tend to mushroom and lower the shear stress. That is the big "if". Normally, hitting it with a liquid jet will make it soft, and overwhelm any surface hardness treatments. A thermally superconductive piece of armour would eliminate this effect, and remain at full hardness for the moment of impact.

As it passes through the outer layers of armor the point of the DU core gets stretched out and becomes sharper in the process. However it has to heat up quite a bit for this to happen. This is at least how I understand it, the exact process and timeframe was explained to me long ago on tanknet

Kinetic penatraitor such as the GAU-8's rounds or APFSDS are not liquid jets, that’s HEAT. They remain solid throughout the entire process, through they may as in the case of the DU become hot enough to deforms while still penetrating.

If they dont, the solid rod will actually lodge inside of the armor. The normal way of repairing this is simply to cut and sand down the back to be flush with the tank armor and then paint it over.

[Darth Wong]

As it passes through the outer layers of armor the point of the DU core gets stretched out and becomes sharper in the process. However it has to heat up quite a bit for this to happen. This is at least how I understand it, the exact process and timeframe was explained to me long ago on tanknet

Ah, so it has to do with geometry. OK.

Kinetic penatraitor such as the GAU-8's rounds or APFSDS are not liquid jets, that's HEAT. They remain solid throughout the entire process, through they may as in the case of the DU become hot enough to deforms while still penetrating.

If they dont, the solid rod will actually lodge inside of the armor. The normal way of repairing this is simply to cut and sand down the back to be flush with the tank armor and then paint it over.

Well, first things first: a thermally superconductive armour plate would rapidly cool the penetrator so that it loses its ductility and becomes harder/more brittle. This will increase the likelihood that the penetrator shatters rather than re-forming itself as it moves inward. Also, the original point about hardness remains: if the armour is much harder than the penetrator, the penetrator's KE will become deformation energy in the penetrator itself rather than the armour.

I checked up that MIL-A-12560 spec mentioned earlier, and it's pretty good, although not remarkable: 800-1000 MPa yield, 20-40J Charpy, 10-15% elongation, 280-430 HB hardness (note that tool steels such as H-13 can hit 1400 MPa yield and 450 HB while still retaining 13% elongation). If we compare this to SW structural materials (see the "Size Matters" page on my site) in which yield strengths in excess of 150-200GPa are required simply to keep ships from buckling under their own acceleration, we're talking about a 100x strength difference, so it's not unreasonable to have 1/8" of their armour handling something that would blast through a 2 inch thick RHA.

[Sea Skimmer]

As it passes through the outer layers of armor the point of the DU core gets stretched out and becomes sharper in the process. However it has to heat up quite a bit for this to happen. This is at least how I understand it, the exact process and timeframe was explained to me long ago on tanknet

Ah, so it has to do with geometry. OK.

Kinetic penatraitor such as the GAU-8's rounds or APFSDS are not liquid jets, that's HEAT. They remain solid throughout the entire process, through they may as in the case of the DU become hot enough to deforms while still penetrating.

If they dont, the solid rod will actually lodge inside of the armor. The normal way of repairing this is simply to cut and sand down the back to be flush with the tank armor and then paint it over.

Well, first things first: a thermally superconductive armour plate would rapidly cool the penetrator so that it loses its ductility and becomes harder/more brittle. This will increase the likelihood that the penetrator shatters rather than re-forming itself as it moves inward. Also, the original point about hardness remains: if the armour is much harder than the penetrator, the penetrator's KE will become deformation energy in the penetrator itself rather than the armour.

I checked up that MIL-A-12560 spec mentioned earlier, and it's pretty good, although not remarkable: 800-1000 MPa yield, 20-40J Charpy, 10-15% elongation, 280-430 HB hardness (note that tool steels such as H-13 can hit 1400 MPa yield and 450 HB while still retaining 13% elongation). If we compare this to SW structural materials (see the "Size Matters" page on my site) in which yield strengths in excess of 150-200GPa are required simply to keep ships from buckling under their own acceleration, we're talking about a 100x strength difference, so it's not unreasonable to have 1/8" of their armour handling something that would blast through a 2 inch thick RHA.

Indeed such would be quite possibul. However the question then arises as to if the material the Empire uses for its ship hulls is super conductive as well.

Indeed such would be highly effective. However the question then arises as to if the material the Empire uses for its ship hulls is super conductive as well.

Guess the A-10 is going to have to call for some Navy laser armed F-35's to deal percision death to the Stormtroopers.

[Patrick Ogaard]

The Acclamators apparently have armor with superconducting properties, at least according to the AOTC ICS. The two-page spread of the Acclamator includes a little pointer to several smudges on the hull, with the note: "Enemy fusion rockets barely score the super-dispersive neutronium-impregnated hull cladding" As far as I can tell, that seems strong indication of superconducting properties.

The ground vehicle AT-TE cross section has a similar note appended: " Highly conductive outer armor spreads heat of enemy fire to minimize penetration"

As far as I can tell, the trick would seem to be to overload the dispersive capacity of the material. Basically, a Star Wars energy weapon attacking armor would have to be able to pump in more energy into the targeted armor than the armor can transport off into the surrounding armor. With sufficient sustained energy input, the armor shell as a whole could break down. Otherwise, a sufficiently powerful energy input should allow a portion of the weapon's energy to poke a hole through the overloaded armor, with predictable results.

It squares neatly with the lack of effectiveness of the snowspeeder laser cannon against the massive slabs of AT-AT armor.

[Master of Ossus]

ISD hulls appear to be designed to stave off energy in the form of heat and radiation. This leads me to believe that they are amazingly conductive. If, indeed, they are enriched with tiny spheres of neutronium, then they would be superconductive.

[Guest]

Damn the godawful use of neutronium. Stupid EU writers. Anyways would'nt hard armor be brittle? I know you could make a composite with something more soft and less brittle, but isn't there a limit? Or could you make a good armor by making many alternating thin layers of hard/soft materials?

[oberon]

Hey man, weapons don't penetrate armor based on force and pressure! Give it up Wong, your boys are toast

[Patrick Ogaard]

Damn the godawful use of neutronium. Stupid EU writers. Anyways would'nt hard armor be brittle? I know you could make a composite with something more soft and less brittle, but isn't there a limit? Or could you make a good armor by making many alternating thin layers of hard/soft materials?

If the word neutronium makes you uncomfortable, mentally substitute the term "superdense matter" for any occurrences of neutronium an you should be fine.

The idea is not to make the armor of neutronium but rather to embed tiny pellets of superdense matter in a matrix of more conventional armor materials. The idea is to impart general radiation resistance and superconductivity to the armor material.

Hard armor does tend to be brittle. That's why steel armor plates usually have a hardened surface layer backed by a softer, thicker layer of steel that provides the necessary "give" to the armor. Modern tank armors include all manner of additions to the complex alloy steel itself, such as embedded rods of even harder metals, layers of ceramic materials, laminated layers of different steels, and even armor panels of depleted uranium encased in steel.

[GrandMasterTerwynn]

Are we talking about the same Stormtroopers who die when Ewoks hit them with rocks or when glancing blaster fire from Rebel fleet boys throws them to their deaths?

I think the Stormies wear paper armour, they would surely die like ants in any type of attack or defense. The Emperor just likes seeing bodies, his or theirs.

Your assertions do not a fact make. Stormtrooper armor is ridiculously good at stopping KE weapons. That does not mean that the stormtroopers are invulnerable to such weapons, in fact the wearer is much MORE vulnerable to such weapons than the armor itself.

This seems to be the case. In ROTJ, the Ewoks used repeated blunt-force trauma to kill stormtroopers, rather than penetrating blows. Note the helmets they seem to be using as bongos at the end of the movie. Presumably these came from dead stormtroopers. The helmets themselves are perfectly intact, but their wearers died from repeated KE transfers (read being hit repeatedly in the head with heavy rocks.)

[Isolder74]

Are we talking about the same Stormtroopers who die when Ewoks hit them with rocks or when glancing blaster fire from Rebel fleet boys throws them to their deaths?

I think the Stormies wear paper armour, they would surely die like ants in any type of attack or defense. The Emperor just likes seeing bodies, his or theirs.

Your assertions do not a fact make. Stormtrooper armor is ridiculously good at stopping KE weapons. That does not mean that the stormtroopers are invulnerable to such weapons, in fact the wearer is much MORE vulnerable to such weapons than the armor itself.

This seems to be the case. In ROTJ, the Ewoks used repeated blunt-force trauma to kill stormtroopers, rather than penetrating blows. Note the helmets they seem to be using as bongos at the end of the movie. Presumably these came from dead stormtroopers. The helmets themselves are perfectly intact, but their wearers died from repeated KE transfers (read being hit repeatedly in the head with heavy rocks.)

yes one of the trade off in using solid armour if you hit it hard enough you can still kill the man underneath even if the armour itself is undamaged.

[Master of Ossus]

Note that we have never once seen stormtrooper armor fail against KE weapons. In the EU we have never seen it fail. What we have seen is stormies get killed by concussive force, which is doubtless what would happen if they were hit by a Vulcan cannon, or similar, even if the armor itself survived.

[Mr. Mister]

So would the concussive force from small-arms fire be enough to kill, even though it couldn't penetrate the armor? How much does the concussive carry-through depend on where you get hit? As I understand it, the same amount of concussive force that can kill when applied to the head may do little more than cause really bad bruising when applied to the thigh or buttocks. But does the armor give the same protection to head and thigh? Are the helmet and breastplate equally protective? Yeah, the joints are obvious soft-spots, but what about the hard white stuff?

[Darth Wong]

This seems to be the case. In ROTJ, the Ewoks used repeated blunt-force trauma to kill stormtroopers, rather than penetrating blows. Note the helmets they seem to be using as bongos at the end of the movie. Presumably these came from dead stormtroopers. The helmets themselves are perfectly intact, but their wearers died from repeated KE transfers (read being hit repeatedly in the head with heavy rocks.)

Minor nit: the stormtroopers in question were probably knocked unconscious and then taken prisoner, rather than being killed outright. If you hit a helmeted man with a big rock, you can knock him unconscious with the concussion (unless it's huge) but he'll live.

[Darth Wong]

So would the concussive force from small-arms fire be enough to kill, even though it couldn't penetrate the armor?

If the shooter can survive the recoil of the weapon, the target can survive the impact, given sufficiently rigid body armour and good internal padding.

How much does the concussive carry-through depend on where you get hit? As I understand it, the same amount of concussive force that can kill when applied to the head may do little more than cause really bad bruising when applied to the thigh or buttocks.

That's because your brain can't survive the sudden acceleration. The human brain is essentially a blob floating in liquid.

But does the armor give the same protection to head and thigh? Are the helmet and breastplate equally protective? Yeah, the joints are obvious soft-spots, but what about the hard white stuff?

The white hard stuff appears to be made out of an extremely strong material, given the EU descriptions. While rigidity and brittleness tend to go hand in hand, it is possible to make an extremely rigid material which still has excellent toughness if the yield stress is extremely high. Given the fact that SW shipbuilding materials seem to be stupendously strong (100x modern-day armour plate), it is quite feasible to make a material which is many times harder than anything we have, while still maintaining sufficient ductility for good impact toughness.

Mind you, I suppose I should point out that such strong materials are not realistic, but the Empire does have the known ability to build these monster-sized ships with very high sublight acceleration, so it's canon and therefore we must simply accept that such materials must exist in SW.

[Master of Ossus]

So would the concussive force from small-arms fire be enough to kill, even though it couldn't penetrate the armor? How much does the concussive carry-through depend on where you get hit? As I understand it, the same amount of concussive force that can kill when applied to the head may do little more than cause really bad bruising when applied to the thigh or buttocks. But does the armor give the same protection to head and thigh? Are the helmet and breastplate equally protective? Yeah, the joints are obvious soft-spots, but what about the hard white stuff?

Not our small arms. Even .50 caliber rounds (the largest ones commonly used) really don't have enough force, except at extremely close range, to do anything more than knock a person off their feet. Even at close range, it would be virtually impossible to knock him out completely. The hard white stuff appears to be about equally protective everywhere, but obviously some parts of the body are more vulnerable than others. It is highly probably that a large caliber hit to the face would snap someone's neck. Obviously this is not a danger if they are hit in the chest. Further, some parts of the armor provide a vastly superior dispersion ability of the force. A hit in the thigh that would cause serious bruising over the entire area may only cause minor bruising to the chest (that would be a HUGE hit). Similarly, the same shot may break bones if it hits an area of the hand, or even forearm, due to the lower surface area and therefore the smaller ability to disperse the impact over a wide area.

[Mr. Mister]

Huh. I wasn't even thinking about surface area when I brought up the thigh. I was just thinking that muscle and fat tissue aren't brittle, while bone is, and the thighbone (femur, right?) is way deeper than most any other bone in your body.

[Master of Ossus]

I see. I thought you were talking about bruising. I don't think that a bullet has enough force to break a femur, if the impact is spread out and cushioned like that.

[hvb]

In the above there seems to be some confusion about how much more powerfull a 30mm DU round is compared with the 10 lbs spear at the given speeds. (Yes I know the conversation has been a bit 'sidetracked' since)

According to http://www.trek-wars.info/swwpower.html, the E-11 does 5e4 to 5e5 joule (minimum - maximum interpretation respectively)

E = ½mv^2 therefore stormtrooper armor can withstand (EU: non-canon):

10lbs spear at 500mph => 2,27e5 joule (~½ of an E-11)

The initial question in the post (and using info from the link to the weapon stats): 30mm GAU-8: .66 kg DU at 1067m/s => 3,76e5 joule (~½ of E-11)

So the 30mm does not carry much more kinetic energy then the spear!

We also need to address the question of how big a surface area is affected by each attack. I would guess that the surface area of a blaster bolt is smaller then the contact area of the spearpoint (at its penetration of a few mm at most), so my conservative estimate becomes that they have, roughly, the same contact area.

Since we thus know that stormtrooper armor can withstand 2,27e5 J, to an area this size, with little to no damage, and that 5e5 J will penetrate it (ANH etc., and superconductivity or not), the energy penetrating a set of stormtrooper armor from an E-11 shot is reduced by at least 45%, and that is assuming that the spear was within 1% of the energy needed to breach the armor, so 45% is a rather conservative estimate!

As we see a stormtrooper get hit by Lea in ANH, and scream before he falls to his death in the shaft, this seems in good correlation with the movie: stormtrooper armor reduces an E-11 hit to the torso to a survivable injury, at least in some cases.


As to the 12.7mm (.50 HMG) round discussion I will just add (completely without supporting evidence whatsoever ) that there today exists armor to protect soldiers from 12.7mm rounds, but this is used only by snipers/security in fixed locations due to the mass, and it only protects the front of the torso.
A helmet is not available for the specific reason that the force of the .50 is big enough to snap the soldiers neck anyway so a helmet would be a waisted effort.

I am of course in the above, for the first time, (& in my first post ) use the old, spam inviting, 'I don't have the link WITH me' excuse. If any of you would be so kind as to search the arms/armour pages on the web, I'm sure you will find it (I found it surfing once, then never saw it again) then drop a link to it somewhere below. Please.

[hvb]

I should add to the 45% reduction above that it also assumes the maximum yield of 5e5 J for the E-11 shot, so it is very much a lowest estimate.
This brackets the protection given by the stormtrooper armor to a very narrow range, provided we can assume that 'energy is just energy' and any special effects from a given weapon will be stopped by the armor if the energy is below this level (and that all weapons affect a like sized area ).

If we assume that the reduction is not greater then 60%, then the E-11 has a yield of at least 3,76e5 J, i.e. at least the same as the GAU-8 DU round. So if a stormie runs into a moder era MBT, he should try to flank it and pump it full of holes with his trusty E-11 (if they have auto-fire settings), or better yet go high in a building and pump 4 double taps into the top armor! Same energy as an A-10 gun, so it should work just fine

[hvb]

I'm just adding to this endlessly ain't I

Incidently if you just scale the 30mm GAU-8 DU down, a 12.7mm (.50 HMG) would at the same speed of 1067m/s have an energy of 2,9e4 J, far less then the spear; likely less then Hans' DL-44 (rated at 10% of the E-11 according to the source in my first post => minimum 2,27e4 J).
So a head shot, or a hit to the armor joints, would be the only way to get rid of a stormie, even if you have a 12.7mm.

A 40mm HEDP would do some serious concussion on a contact detonation, so getting hit by one in the chest would likely be fatal to the stormie, but I am not in trauma medicine, so I don't know. Lets look at penetartion:
4,19e6 J / kg TNT, half that goes the wrong direction, the rest is focused on a small area (that same magical area again ), so at least 25 gram of TNT is needed to equal an E-11; a 40mm grenade weights over 454 gram, so it obviously carries more then this => The shape charge would penetrate better then the E-11. The Stormie is TOAST

This is the last for a while, honest.

[Connor MacLeod]

It seems the thread has gotten a bit off track:

I was wondering how reliable the assessment of stormtrooper armor being bulletproof is.

And it got me to thinking about something else: could an A-10 Thunderbolt II's GAU-8/A main gun firing PGU-14/B Depleted Uranium Incideniary shells punch through the armor of an AT-AT at any range? And if it could, what would the maximum effective range be?

Using information I found on the internet, which gave the weight of the depleted uranium core of the shell at roughly .60 pounds (which translates to roughly .27 kg mass), and the gun's muzzle velocity at 3325 ft/s (roughly 1013 m/s), I worked the muzzle kinetic energy of the round out to be 1.4x10^5 Joules. So, first off, am I messing something up? And if I'm not, is that enough kinetic energy to punch through an AT-AT's armor, at any point, when applied to an object with a .27 kg mass and a diameter of .015 meters (the entire shell is .030 meters, but I found a .015 m diameter stated for the uranium core, and that's the only part I'm using in my energy calculation.)

How would a modern-day army fare against the Imperial army, if units were committed in reasonable quantities (I'm not saying they have to be equal, just that they should be nothing silly, like the entire Imperial army against one U.S. army division, or the whole PLA against only one ISD's ground compliment)? For that matter, would something like an F-22 or a MiG-29 be any sort of threat against TIEs in atmospheric combat?

Note that he's stacking the A-10's GAU gun against an AT-AT, not a stormtrooper. The mentioning of the stormtrooper armor is incidental.

Coincidentally, both the Clonetrooper rmor and stormtrooper armors are mentioned in the AOTC VD and Trilogy VD (respectively) as having very high resistance to most SW-grade projectile weapons (given that Zam Wessel's rifle is credited with firing electromagnetically-accelerated bullets, this perhaps gives us a good idea of what they're dealing with). The AOTC VD expands on this to infer that the armor not only protects well against projectiles, but also against explosions and passing through deflector shields (the kinds that would incinerate/vaporize an unarmored human).

IIRC the Trilogy VD also credits stormtrooper armor with being layered, one of the layers being an anti-laser mesh (some form of superconducting material I suspect.) - the armor is also given "heat sinks" IIRC, which further reinforces the superconducting nature of the armor.

As for AT ATs.. no idea. We know AT-TE's, LAAT's, and Acclamators have super-dispersive/superconducting hulls - the AT-AT probably does too. How it fares against projectiles is anyone's guess. The closest comparison I could think of would be a proton torpedo from Rogue Squadron that punched through the hull of a Juggernaut tank (in many ways supposedly comparable to AT-ATs) before detonating. No idea how fast the missile was traveling - given that LAAT gunship rockets are hypersonic (and that ships are supersonic) we can probably infer a speed comparable to that bullet, with probably greater mass.

I'll have to check other osurecs to be sure, though.

[Failed Glory]

Are we talking about the same Stormtroopers who die when Ewoks hit them with rocks or when glancing blaster fire from Rebel fleet boys throws them to their deaths?

I think the Stormies wear paper armour, they would surely die like ants in any type of attack or defense. The Emperor just likes seeing bodies, his or theirs.

Your assertions do not a fact make. Stormtrooper armor is ridiculously good at stopping KE weapons. That does not mean that the stormtroopers are invulnerable to such weapons, in fact the wearer is much MORE vulnerable to such weapons than the armor itself.

I never said the armour wasn't great at absorbing energy, I just mean that it's obviously useless in protecting the wearer from any type of death, KE, PE, EE, CE, whatever e you do, that stormtrooper seems to die.

You never saw a Stormtrooper with a blast mark on his armour, but so what, he was still dead from the blaster fire he caught in the chest.

[Sea Skimmer]

I'm just adding to this endlessly ain't I

Incidently if you just scale the 30mm GAU-8 DU down, a 12.7mm (.50 HMG) would at the same speed of 1067m/s have an energy of 2,9e4 J, far less then the spear; likely less then Hans' DL-44 (rated at 10% of the E-11 according to the source in my first post => minimum 2,27e4 J).
So a head shot, or a hit to the armor joints, would be the only way to get rid of a stormie, even if you have a 12.7mm.

A 40mm HEDP would do some serious concussion on a contact detonation, so getting hit by one in the chest would likely be fatal to the stormie, but I am not in trauma medicine, so I don't know. Lets look at penetartion:
4,19e6 J / kg TNT, half that goes the wrong direction, the rest is focused on a small area (that same magical area again ), so at least 25 gram of TNT is needed to equal an E-11; a 40mm grenade weights over 454 gram, so it obviously carries more then this => The shape charge would penetrate better then the E-11. The Stormie is TOAST

This is the last for a while, honest.

Modern weapons don't scale linearly. For example the KPV's 14.5mm round has about twice the muzzle energy of a 12.7mm round.

A four inch shell weights about 32 pounds, five inch 50-65.