|
Cyrano4747 posted:There is actually a fair bit of naval-gazing about why this is so that has taken place within the scientific and mathematical communities. I'm not 100% dialed into it, so I won't attempt a summary, but you'd probably do well to at least familiarize yourself with the arguments and conversations spawned by Wigner's "Unreasonable Effectiveness of Mathematics in the Sciences." As I recall a bunch of the counter-arguments are from mathematicians who actually point out that humans create and select mathematics to fit a situation, which perhaps says more about the mathematics in question than the underlying physics (it's almost always physics used as an example in these) they are seeking to describe. Well, chosing math badly fitting to the underlying physics would be stupid, anyway. I have to go with Wigner here. quote:
What the hell would a "natural" division in this context even be? A direct message from god? Our mind connecting with Kether itself and downloading pure, incomprehensible truth from deep within the air which can not be grasped? Mathematics and logic are philosophical tools to allow a fallable human mind to make the attempt to comprehend things that can by their very nature not be comprehended. Everything we do is artificial, we just can do our best to at least try for some kind of sensible structure. That's why lifeforms in biology nowadays are grouped on base of their genetical affinities, instead of shell colors and -patterns like the scientists of the 19th century preferred. But at this point I think we should shelf this meta-discussion for another, more philosophy-oriented thread. We're only very indirectly linked with military history here. 
|
#
?
Aug 17, 2014 23:37
|
|
|
|
| # ? May 28, 2024 22:36 |
|
|
PittTheElder posted:These are the things I find rather surprising, probably an effect of modern media. I knew tanks were primarily used in anti-infantry ops, but I assumed there would also have existed a good HE round for the 76mm or 17lb guns. Although I suppose you'd then have to retool your factories to make adequate supplies of shells of both sizes, and move supplies of both, etc., which would be a hassle. The 76 mm HE shell was just not as good as the 75 mm, but the 17-pdr had an abysmal HE shell. Yes, making new shells is a hassle, and a reason why some armies are unwilling to move up from a certain caliber once they have a bunch of guns in it. PittTheElder posted:Which brings me to my next question: when a tank gets hit, what exactly is it that knocks it out, assuming the engine isn't hit? Shell fragments and spall cooking off your ammunition is an obvious risk, but if your rounds are wet racked or outside the crew compartment, how much danger is the crew in from overpressure or spalling? Is a significant amount of heart actually transferring into the crew compartment? Curious about both WW2 era tanks and modern ones, if people happen to know. What gets your rounds to cook off isn't spalling it's fire. If your fuel tank gets hit, your tank will almost certainly catch fire. In that case, you want to get the gently caress out, because once the fire gets to the ammunition, that tank is going to fly into pieces. Well designed ammo racks will have the rounds go pop one by one, but you still don't want to be around when that happens. Spalling might also kill one or two of your crewmen, depending on what compartment it goes into, but you might still be able to return fire. What really gets you is if the AP-HE shell detonates inside your tank, then you all or most of your crew will die. I haven't read anyone write about heat, I don't think that's enough to kill you, or even that dangerous compared to all the other things that happen.
|
|
#
?
Aug 17, 2014 23:44
|
|
|
What is it that's causing all the T-72 and such in Syria to explode in such a dramatic fashion after taking RPG hits? It must be the ammo cooking off, but it all happens in a few seconds, and I'd be amazed if there was enough time for a fuel fire to get going. And that should be with just a copper jet penetrating the fighting compartment, not any explosives.
|
|
#
?
Aug 17, 2014 23:50
|
|
|
PittTheElder posted:Which brings me to my next question: when a tank gets hit, what exactly is it that knocks it out, assuming the engine isn't hit? Shell fragments and spall cooking off your ammunition is an obvious risk, but if your rounds are wet racked or outside the crew compartment, how much danger is the crew in from overpressure or spalling? Is a significant amount of heart actually transferring into the crew compartment? Curious about both WW2 era tanks and modern ones, if people happen to know. Well spalling is literally bits of steel flaking off, so if you have interior spalling in a tank from a shell impact that's basically shrapnel being sent flying inside your crew compartment, so that would be a pretty big danger to the crew. There's lots of parts of a tank that could be damaged and not make it totally incapable of operating, but more or less ineffective for combat - the turret ring could be jammed, the gun itself could be damaged, the tracks and wheels could be disabled...and once any of those happen, most crews probably would not want to stick around in a combat situation, so either they pull the tank back, or maybe just outright bail. And don't forget that tanks also have fuel tanks, as well, which can start fires or even outright explode. I believe Ensign Expendable's blog actually had a post on the particular fuel levels inside a fuel tank that would create an optimal fuel/air mix for catastrophic explosions.
|
|
#
?
Aug 17, 2014 23:57
|
|
|
PittTheElder posted:What is it that's causing all the T-72 and such in Syria to explode in such a dramatic fashion after taking RPG hits? It must be the ammo cooking off, but it all happens in a few seconds, and I'd be amazed if there was enough time for a fuel fire to get going. And that should be with just a copper jet penetrating the fighting compartment, not any explosives. The autoloader in the T-72 requires loading trays that have no particular protection, which causes ammunition to blow up all the time. Combined with the middling protecion of the T-72M and M1s that the Syrians have, that's what makes them blow up so much.
|
|
#
?
Aug 18, 2014 00:05
|
|
|
Phanatic posted:This is still basically true today. The Abrams and other modern MBTs are ridiculously effective against HEAT warheads from the front, but cheap, man-portable weapons can still penetrate large areas of them, and the protection they offer comes at the cost of making them only air-portable in a technical sense and unable to make it across a whole lot of bridges. This is also the reason why tankers have practised snorkeling ever since WW2. Well, partly because enemies may have blown up all bridges, and partly to force the enemy to keep guessing on where your tanks might cross a particular river. But also because none of the available bridges would support the weight of your vehicle and you don't want to wait for combat engineers to build a new bridge for you. https://www.youtube.com/watch?v=y-QWQsDNsRs https://www.youtube.com/watch?v=He9KXalXnv8 Ensign Expendable posted:What gets your rounds to cook off isn't spalling it's fire. If your fuel tank gets hit, your tank will almost certainly catch fire. In that case, you want to get the gently caress out, because once the fire gets to the ammunition, that tank is going to fly into pieces. Well designed ammo racks will have the rounds go pop one by one, but you still don't want to be around when that happens. No one would wait for that. The engine catching fire is not some insta-death event like the ammo cooking off is. Fuel on fire still leaves time for the crew to exit (they may not even immediately notice it but it will get intolerable due to smoke before it gets really hot) and at any rate once the fire spreads the TNT will fizzle and sizzle in fire harmlessly compared to the violent explosion resulting from a penetrating kinetic shot or hollow charge hitting the ammo. Back to the question, it should be plenty of uncomfortable to have your tank's armour penetrated. You may get physically disabled by fragments, systems may get disabled, it may start fires, just the hit alone may nauseate you and you will become aware that you are being targetted by some motherfucker who can pierce your armour. Assuming that you have other plans for your life, having your impenetrable vehicle penetrated is bad news.
|
|
#
?
Aug 18, 2014 00:24
|
|
|
Libluini posted:What the hell would a "natural" division in this context even be? I think there's a bit of a linguistic breakdown here. By "not a "natural" division" I was saying that these divisions weren't based in any property unavoidably inherent to the fields themselves. That doesn't imply the existence of such a division, just acknowledges that any division we choose to make is going to be a philosophical construct open to debate and revision. Think of the division drawn in legal theory between malum in se and malum prohibitum as a kinda-parallel. Although in truth now that I think about it I might have to step back on that equivocation, because the initial division between empiricism and criticism might actually be defensible as an "in and of itself" distinction. . . But yes, I think we're the only ones interested in this at this point. If you want to take it to the general history thread in that might be a better place for it, as it as the question that sparked this all was (as I recall) one of how history related to the sciences. I'd also be fine with just letting it drop as well.
|
|
#
?
Aug 18, 2014 01:20
|
|
|
Ensign Expendable posted:The 76 mm HE shell was just not as good as the 75 mm, but the 17-pdr had an abysmal HE shell. Yes, making new shells is a hassle, and a reason why some armies are unwilling to move up from a certain caliber once they have a bunch of guns in it. To add onto that, the 17-pdr (a 76.2mm gun) and the 76mm get their additional penetrating power by shooting the shell at a higher velocity than the old 75mm. To reach that higher velocity, they accelerated the shell faster, which means more pressure on the shell. This requires a larger and stronger steel case, resulting in less room for high explosives. In particular, the 75mm HE shell had about 1.5 lbs of explosive inside, but both the 76mm and 17-pdr shell had less than 1 lbs of explosive in them.
|
|
#
?
Aug 18, 2014 01:30
|
|
|
Panzeh posted:The autoloader in the T-72 requires loading trays that have no particular protection, which causes ammunition to blow up all the time. Combined with the middling protecion of the T-72M and M1s that the Syrians have, that's what makes them blow up so much. To be more precise, the ammo storage in a T-72 is oriented in a big ring in the lower half of the tank. This presents an abnormally large area for John Q. RPG if he wants to hit something that'll make a big impression. The tank isn't actually a total death-trap, but the Syrians like camping lone tanks in isolated intersections surrounded by buildings, which is a puzzling tactic. RPG-7s don't penetrate the front armour of the T-72, or that of most other tanks.
|
|
#
?
Aug 18, 2014 01:31
|
|
|
vintagepurple posted:In general it's always seemed to me that being packed shoulder-to-shoulder like that would result in lots of wounded and dead piling up really close to eachother, which would be a lot more tactically problematic than when the casualties are dispersed like in later wars. That's pretty much how it worked. you could tell where men were advancing/retreating under fire by the trail of wounded and dead as well you could tell where the lines stood and slugged it out. Sometimes units would send out a small detachment in advance to clear out the area a bit, but mostly any advance over contested field by troops prior means you were going to be stepping over the wounded and dead on your way not to mention demoralizing greener troops.
|
|
#
?
Aug 18, 2014 01:52
|
|
|
Cyrano4747 posted:It's also really, really obviously aimed at the 14-24 year old crowd. They layer in modern music in places in a way that I honestly found obnoxious but which someone fifteen years younger - or maybe just with less of a stick up their rear end - would probably find pretty cool. feedmegin posted:Uhhh. If you mean a branch at the machine code level, yes, every program you use does and it doesn't depend on the chip type. Bit hard to have useful programs without them.
|
|
#
?
Aug 18, 2014 01:53
|
|
|
Hogge Wild posted:Why did America make tank destroyers? US tank doctrine, as I've read in the past, was tanks advance and support infantry. Tank destroyers fight tanks. Obviously reality doesn't work like the field manual says it should On the tank explosion topic. While fuel is the favorite boogy man for people to bring up when it comes to Shermans, it was more often just shrapnel and whatnot kicking off an explosion. German AP rounds did have an explosive packed inside. Pretty much everyone's tanks ran on gas, the Shermans are the only ones really noted for fire issues though because the ammo had little protection. Once they started adding extra plate and wet stored it, the explosion/fire issues dropped considerably. SocketWrench fucked around with this message at 03:16 on Aug 18, 2014 |
|
#
?
Aug 18, 2014 01:56
|
|
|
Speaking of cold war tanks, how was the parallel development and deployment of tanks during the cold war between NATO and the Warsaw Pact/USSR? The impression I got, particularly from Red Army is that the Soviets gradually settled into a quantity > quality paradigm to fight with their doctrine of deep operations of having many tanks to attack many places along the front to exploit weaknesses in the enemy line (because their tanks can't be everywhere); while NATO seems to have eventually trended towards 'quality' of having larger, more heavily armored tanks.
|
|
#
?
Aug 18, 2014 01:57
|
|
|
Nenonen posted:No one would wait for that. The engine catching fire is not some insta-death event like the ammo cooking off is. Fuel on fire still leaves time for the crew to exit (they may not even immediately notice it but it will get intolerable due to smoke before it gets really hot) and at any rate once the fire spreads the TNT will fizzle and sizzle in fire harmlessly compared to the violent explosion resulting from a penetrating kinetic shot or hollow charge hitting the ammo. There are a bunch of stories of Soviet heroes gloriously fighting in a burning tank until the ammo goes off. My favourite one is the guy that rammed a train in this condition.
|
|
#
?
Aug 18, 2014 02:19
|
|
|
Raenir Salazar posted:Speaking of cold war tanks, how was the parallel development and deployment of tanks during the cold war between NATO and the Warsaw Pact/USSR? The impression I got, particularly from Red Army is that the Soviets gradually settled into a quantity > quality paradigm to fight with their doctrine of deep operations of having many tanks to attack many places along the front to exploit weaknesses in the enemy line (because their tanks can't be everywhere); while NATO seems to have eventually trended towards 'quality' of having larger, more heavily armored tanks. The problem with talking about tanks in generalities like this is that you kind of gloss over the specifics. On both the NATO and WP sides of the curtain, there were modern whizz-bang tanks, ww2-era relics, and everything in between. There is, however a convergence of organizations on both sides from WW2 that gives you armor-motorized infantry teams as the basic front line organization, with varying mixes of tanks and motorized infantry, no one went on foot. The USSR had a massive army, at least in theory, but the forces deployed in Germany were not that much more numerous than what NATO had deployed there. Of course, in Germany you also had the cream of the Soviet army there, the T-80s, T-64s, etc. What really gave the Warsaw Pact their scary numbers were the district forces, which had anything from T-34-85s to T-72s. The big difference here is that the district troops were kept active in a way the National Guard, for example, were really not. The Soviets were also far more willing to keep older AFVs in use and modernized their T-55s and T-62s quite heavily. The 70s were a bad time in NATO tank design history, because the MBT/Kpz-70 was a big bust, way too ahead of its time for its own good, but some of it got made into what were eventually the Leopard 2 and M1 Abrams, which is what's traditionally thought of when we think of NATO tanks(neither the M60A3 nor the Leo 1A4/5 was not a great match for the later model T-64s, T-72s, or T-80s). That all being said, technical differences aren't the be-all and end-all, and the level of training and readiness would probably have determined the outcome more than technical differences. The different eras of tank design are really interesting in how they reflect prevailing thought of the day. For example, the Leopard 1 and AMX-30 were designed in an era where people thought ATGMs would make tanks obsolete, so armor wasn't really considered important in these designs.
|
|
#
?
Aug 18, 2014 02:25
|
|
|
SocketWrench posted:US tank doctrine, as I've read in the past, was tanks advance and support infantry. Tank destroyers fight tanks. Obviously reality doesn't work like the field manual says it should US tank doctrine was more that tanks fight what it takes to support the infantry and this includes tanks, while tank destroyers are there as a reserve in case of massed armored attack. There was a conception of Blitzkrieg as this really tank-based massed armored attack in the States, so they thought that they'd need forces to deal with tanks and tanks alone. That led to the weird tanks and tanks alone design of TDs, which were designed to be mobile in getting to positions to deal with enemy tanks, and weren't really fitted out to deal with supporting forces. This is not actually what German armored doctrine looked like. Regarding the Sherman ammunition, the ammunition was in the sponsons behind ~40 mm of armor, and in later versions was placed behind applique armor. The Panther had it behind ~55 mm of armor. Once the Sherman had the appliques (external plates were 25.4mm thick, and there were apparently inner plates), it had thicker armor over the ammunition rack. In later models it was moved to wet storage on the bottom of the hull, where it was basically the best stored ammo of any tank of the war, but even before then the applique armor was common enough the Panther had considerably worse protection over the racks.
|
|
#
?
Aug 18, 2014 05:36
|
|
|
xthetenth posted:US tank doctrine was more that tanks fight what it takes to support the infantry and this includes tanks, while tank destroyers are there as a reserve in case of massed armored attack. There was a conception of Blitzkrieg as this really tank-based massed armored attack in the States, so they thought that they'd need forces to deal with tanks and tanks alone. That led to the weird tanks and tanks alone design of TDs, which were designed to be mobile in getting to positions to deal with enemy tanks, and weren't really fitted out to deal with supporting forces. This is not actually what German armored doctrine looked like.  As seen in the diagram above, the big problem with Sherman ammo stowage wasn't necessarily that it was poorly protected (Though it was in the early models), but that it was everywhere. The tank was filled to the brim with 75mm shells and .30/.50 caliber machine-gun ammunition, so whenever a Sherman took a penetrating hit from any angle there was a good chance an ammunition box would find itself in the way of the shell. Moving the main gun ammunition to the bottom of the hull in "Wet Racks"* helped to reduce the rate of ammunition fires significantly, from the percentage of up to 80% of Shermans burning after suffering a penetrating hit to only 15%. wdarkk posted:Wouldn't a breakthrough tank have been pretty useful for the hedgerow areas? Granted it wouldn't be as useful once you left. The problem with fighting through the hedgerows was that Normandy was just flat-out hostile terrain for armored vehicles, both on the German and American sides. Tanks were only able to effectively move down roads (Which could be mined), and given the many bends and turns in the road could very easily be ambushed by anti-tank guns or anti-tank infantry. Going through the hedgerows themselves was an option, but a dangerous one, as it risked exposing the exceptionally thin bottom armor of the tank to enemy infantry and anti-tank guns. To get through them, American engineers and tankers adopted a number of tactics, including one novel solution wherein a tank would be equipped with huge steel prods that would be driven straight into a problamatic hedgerow, creating holes that would be filled with explosives used to blow the whole thing apart. Later on, American engineers began fastening huge steel forks made from discarded beach obstacles to the fronts of their tanks, allowing the Shermans to simply push through the hederows straight-on as opposed to having to drive over them. Of course, by that time it was already July, and after Operation Cobra their usefulness became moot. However, another obstacle remained in the future, which the Americans were clearly aware of: The German Siegfried Line, the heavily-fortified border between Germany and France. Recognizing the need for vehicles to go through and destroy the heavy German defenses, the Army authorized the creation of a thickly-armored variant of the Sherman, numbered M4A3E2 and nicknamed the "Jumbo".  Compared to the normal Sherman, the Jumbo was a monster. Featuring four inches of armor on the front plate (The original Sherman had 2) and 7 inches of armor on the turret front, the Jumbo could take hits from Panthers, Tigers, and all but the heaviest German towed anti-tank guns and keep on trucking. Not surprisingly, as soon as they were made available they became incredibly popular and were in exceptionally high demand, but the Army had underestimated how many they would need and only 250 were ever built. Originally equipped with 75mm guns, many were retrofitted with 76mm guns and were placed at the front of American armored attacks to absorb the shots the other, less well-armored tanks couldn't take. Of course, given the low production run of the Jumbos they were somewhat rare, but that didn't stop American engineers from trying to make their own. As the American army fought through France and Germany various Shermans were "upgraded" with whatever extra armor they could get their hands on, from sandbags (Which Patton explicitly banned in the Third Army, citing their ineffectiveness and concerns that the weight would prematurely wear out the transmission), spare steel plates, and, in some cases, concrete. The culmination of these upgrade jobs was probably the famous T26 "Super Pershing", which was a Pershing tank fresh from the States that had been upgraded with a longer, higher-velocity 90mm gun. Of course this wasn't enough for American ingenuity, and the engineers of the 3rd Armored Division decided to upgrade it further by welding additional armor plates from an abandoned Panther to the front, making it one of the most heavily armed and armored tanks in Europe for its brief existence. *For those who don't know, "Wet" ammunition racks are specialized ammunition stowage in which each shell is immersed in water or antifreeze in individual compartments within the ammo box. By separating the shells and placing them in a nonflammable liquid, it helps to prevent shrapnel from detonating a shell within the rack and prevents the explosion from setting off the rest of the ammo if a shell is penetrated. First used in the 76mm-armed variant of the M4A1 which debuted in Operation Cobra, they were later used in every variant of the M4A3. Acebuckeye13 fucked around with this message at 14:48 on Aug 18, 2014 |
|
#
?
Aug 18, 2014 14:44
|
|
|
Slavvy posted:I thought the abrams/challenger were basically impenetrable to shoulder mounted weapons. Didn't a few abrams break down/get disabled in Iraq and have RPG's just ping off them until they were recovered? Or is this just a matter of new technology vs 30 year old technology? From the front, where the fancy composite Chobham armor is, they're basically impenetrable, but that's also why they weigh 70 tons and much of the tank is still protected by plain old RHA steel. Modern tandem-warhead RPG rounds can penetrate something like three-quarters of a meter of that. There was one case in Iraq where the penetrator went through the side of the tank, through the crew's compartment, and penetrated into the armor on the other side of the tank, leaving a smear of copper liner across one of the crew's armor vest. The Abrams is the first tank where "crew survivability" was the #1 design priority. "Transportability" was the lowest priority. So basically it's the exact inverse of the Sherman.
|
|
#
?
Aug 18, 2014 15:04
|
|
|
Phanatic posted:From the front, where the fancy composite Chobham armor is, they're basically impenetrable, but that's also why they weigh 70 tons and much of the tank is still protected by plain old RHA steel. Modern tandem-warhead RPG rounds can penetrate something like three-quarters of a meter of that. There was one case in Iraq where the penetrator went through the side of the tank, through the crew's compartment, and penetrated into the armor on the other side of the tank, leaving a smear of copper liner across one of the crew's armor vest. Just about all of the visible armor on an M1 is the composite stuff, and all models fielded now have DU plating integrated everywhere on top of the composite...there isn't much steel in the construction outside of the chassis. Also the only model that gets near 70 tons is the A2 with the TUSK stuff strapped on.
|
|
#
?
Aug 18, 2014 15:26
|
|
|
What happens to Abrams when it gets hit by an anti-tank missile? How good are the anti-missile defenses on modern tanks?
|
|
#
?
Aug 18, 2014 15:45
|
|
|
Hogge Wild posted:What happens to Abrams when it gets hit by an anti-tank missile? Chobham armor is extremely resistant to the HEAT warheads used on anti-tank missiles, and the Abrams maximum armor is often reckoned as equivalent to something like 1300-1600mm of RHA (rolled homogeneous armor). Later model Abrams with the additional depleted uranium would obviously be even tougher. By way of comparison RPG-type weapons top out at around 750mm RHA penetration. The latest Russian ATGMs have warheads that will defeat 1000-1200mm RHA. Hits by either class of weapon to the glacis or turret of an Abrams would probably fail to inflict serious damage. The missile would hit, fail to penetrate, and the Abrams would keep rolling. Hits to the turret have the potential to damage sensitive optics, electronic equipment, or even the gun, but that can be repaired. Hits from those weapons to the sides or rear where the armor is thinner are more dangerous and could result in the tank being disabled or destroyed. Like most tanks, the Abrams would probably be destroyed outright by a top-attack missile like the Javelin, which launches in a high arc to descend vertically and strike the weak top armor. So far it hasn't encountered an enemy with access to those. quote:How good are the anti-missile defenses on modern tanks? Are you asking about their armor, or about active anti-missile defenses? Composite armor like chobham and reactive armor such as that used on most Russian tanks are both very good at defeating conventional HEAT warheads, although reactive armor can be beaten by tandem charge warheads. Active protection systems are pretty new. The Russian Arena system uses a radar on the turret to detecting incoming projectiles, then launches an explosive charge that detonates into a cone of shrapnel that intercepts the projectile. These apparently work pretty well but they have some disadvantages, mainly that you can't use them if friendly infantry are nearby because they're likely to get caught in the detonations.
|
|
#
?
Aug 18, 2014 16:40
|
|
|
Yeah, I was asking about active defenses.
|
|
#
?
Aug 18, 2014 16:56
|
|
|
EvanSchenck posted:Hits from those weapons to the sides or rear where the armor is thinner are more dangerous and could result in the tank being disabled or destroyed. Like most tanks, the Abrams would probably be destroyed outright by a top-attack missile like the Javelin, which launches in a high arc to descend vertically and strike the weak top armor. So far it hasn't encountered an enemy with access to those. It's going to be a bad day for western armies when Russia and China start selling their own top-attack missiles. Currently the best missiles and RPGs in the Russia & friends' kit rely on the brute force of a big rear end tandem warhead, like on RPG-29 or 9M123 Khrizantema. It wouldn't be weight economical to cover the top of a tank's turret and hull with enough armour so the solution has to be some type of active defense system. Some of the suggested solutions include electric "force fields" that would "scorch" the missile's jet when it comes to contact with the vehicle and it's just  Missile test videos are also awesome to watch https://www.youtube.com/watch?v=lIVtB-8fQ7E Btw. is that a SU-100 tank destroyer at 1:17 mark? Because it's a bit of an overkill if so https://www.youtube.com/watch?v=zWy_-zW0NNo this video is very confusing in other respects too, not the least due to the 1980s music, narrator and overall quality contrasted with state of art gizmo
|
|
#
?
Aug 18, 2014 17:24
|
|
|
How far can the jet from a HEAT warhead travel in air? Like, I know spaced armour is a thing, but hypothetically if you didn't care about visibility, couldn't you put a steel plate on stilts like a metre or two above the top if a tank and hope that couple metre gap of air dissipates the jet from a top attack warhead?
|
|
#
?
Aug 18, 2014 17:33
|
|
|
That's why tandem warheads were invented. Plus, all that poo poo would make the tank tougher to transport and drive.
|
|
#
?
Aug 18, 2014 17:54
|
|
|
Mr Luxury Yacht posted:How far can the jet from a HEAT warhead travel in air? It's not really a jet. What's going on is you're using the force of the explosive warhead to shape and propel a penetrating slug of copper. At the pressures involved the distinction between "solid" and "liquid" pretty much disappears; the metal liner of the warhead doesn't have *time* to melt and vaporize into a jet or a plasma or anything, and it doesn't burn or melt through the armor. The armor deforms plastically and yields, it's more like pushing a screwdriver through an empty beer can. The penetrator could travel quite a ways through air, since you're talking about a lump of metal that you've accelerated to Mach 25. But the geometry of the warhead is intended to focus all that force on a small area of the target, and HEAT penetration is extremely sensitive to standoff distance; if the warhead detonates too close to the target the liner doesn't have time to collapse into the smallest frontal area before it encounters the armor, and if the warhead detonates too close away the liner will already have collapsed and begun to disperse again. In either case the larger area of the armor it's pushing against means that penetration falls off fast. So while the penetrator could travel some large distance after only a little distance it's not going to be much use at penetrating. You've seen the cage armor around Strykers and other LAVs? Part of the utility of that is it can cause incoming rounds to detonate early, while they're too far away for optimum penetration (The other is that if the nose fuse misses the slats of the gage and the side of the warhead hits a slat it'll crush the side of the cone and short out the electrical path between the fuse and the detonator at the base and the round will be a total dud but that only works against certain weapons, I think the newer RPG warheads have corrected that design issue). quote:Like, I know spaced armour is a thing, but hypothetically if you didn't care about visibility, couldn't you put a steel plate on stilts like a metre or two above the top if a tank and hope that couple metre gap of air dissipates the jet from a top attack warhead? Yes. But then I could do what's already done against ERA and the like, use a tandem warhead where the first warhead removes your steel plate and then the second one detonates at the proper standoff distance. Or I don't use a HEAT warhead for top attack, I use an EFP (explosively-forged projectile) instead. Similar construction but different principle of formation, and penetration is not greatly affected by standoff distance. The downside is that where a HEAT warhead can penetrate something like 6 or 7 times the charge diameter in thickness, an EFP might be able to penetrate about the same as the charge diameter. bewbies posted:Just about all of the visible armor on an M1 is the composite stuff, and all models fielded now have DU plating integrated everywhere on top of the composite...there isn't much steel in the construction outside of the chassis. Also the only model that gets near 70 tons is the A2 with the TUSK stuff strapped on. The side skirts and engine deck armor are still basically just RHA, no?
|
|
#
?
Aug 18, 2014 17:57
|
|
|
The armor thickness and quality (as in advanced/composite vs. RHA) also goes down as you move back along the sides. The front third/half will be more protected than the next bit, and so on.
|
|
#
?
Aug 18, 2014 18:11
|
|
|
Mr Luxury Yacht posted:How far can the jet from a HEAT warhead travel in air? Some vehicles use a system like this, the Stryker comes to mind where they have a mesh armor extended out from the hull to defeat RPG attacks and the like much like the Schürzen used on German WWII tanks.
|
|
#
?
Aug 18, 2014 19:12
|
|
|
Phanatic posted:The side skirts and engine deck armor are still basically just RHA, no? Everything armored is composite/DU. Steel encases the composite/DU and most of the structure/chassis is steel all of the protective elements are composite/DU. There might have been steel armor on the original M1 though, that I don't really know anything about.
|
|
#
?
Aug 18, 2014 19:17
|
|
|
SocketWrench posted:Some vehicles use a system like this, the Stryker comes to mind where they have a mesh armor extended out from the hull to defeat RPG attacks and the like much like the Schürzen used on German WWII tanks. The slat armour cage on Stryker is designed to mangle the detonator so that the shell doesn't detonate in the first place. Which is desirable since the vehicle itself is so lightly armoured, even with extra stand off range it doesn't amount to much. Fun fact, German Schürzen was designed to counter Soviet anti-tank rifles.
|
|
#
?
Aug 18, 2014 19:34
|
|
|
Hogge Wild posted:What happens to Abrams when it gets hit by an anti-tank missile? The answer to the first is, if it is a modern heavy multistage missile or a top attack missile, it will blow up. If it is anything lighter, it will not do a whole lot unless it hits a very vulnerable area. To the second, I would say in general the answer is not particularly good. The first generation of active systems have essentially already been outmatched by very simple decoy systems. The next generation of systems (at least for the US) are not really even attempting to counter the highest end ATGMs, but rather things like heavy RPGs. Of course none of this gets anywhere near defeating things like long range precision artillery that is now accurate enough to effectively target single tanks. I've argued this in here before, but all this stuff leads me to think that the era of relying on armor as your first choice in protection is rapidly coming to a close.
|
|
#
?
Aug 18, 2014 19:52
|
|
|
Books and movies have led me to believe that we should be living in an age where active point defence supersedes actual armour and I am sorely disappointed by the reality.
|
|
#
?
Aug 18, 2014 20:05
|
|
|
So, this weekend I met a guy who also does Napoleonic reenactment (he invited me to Waterloo next year, it's the anniversary and it's gonna own). He and his bros portray the Black Brunswickers--all black, death's head on their shakoes, etc, and he said a tourist told him once "I didn't know they also had the SS in the Middle Ages." Which is not as bad as the time a tourist came across a pair of guys heating a tub of water to have a bath, dipped her fingers in the tub, and said "It feels just like actual water!" The only time something like that happened to me is when I handed a pike to some guy and he staggered a little, and said "I thought they were plastic." It's also very difficult to keep them from smoking next to containers of black powder.
|
|
#
?
Aug 19, 2014 09:47
|
|
|
Unfortunately the Nazis perverted quite a few things that the lay person just doesn't get. Best reenactment moment I ever witnessed was while working artillery. Some guy asked why we put powder in the cannon instead of just a cannonball. I wanted to say something sarcastic like "Well we like to gussy up our cannonballs to make them presentable" but the colonel responded faster than I could. Best moment I heard of was a civil war reenactment where the guys were waiting to get going. One Yankee turned his hat around backwards and crept close to the crowd with his rifle like he was hunting, looks up, places a finger to his lips and says "Shhhh, be vewy vewy quiet. I'm hunting webels, huhuhuhuhuhuhuh"
|
|
#
?
Aug 19, 2014 10:18
|
|
|
HEY GAL posted:Tourists at re-enactments. From when I did ACW re-enactments with my best friend, I've seen more than a few tourists comment on how the mannequins (us) were so realistic. Nobody seems to mind when Jesus comes by and moves the casualties to the shade, though.
|
|
#
?
Aug 19, 2014 10:37
|
|
|
HEY GAL posted:"I didn't know they also had the SS in the Middle Ages." That is spectacularly stupid. Years in tech support tell that it can get alot worse. These people are allowed to operate cars.
|
|
#
?
Aug 19, 2014 10:54
|
|
|
PittTheElder posted:Which brings me to my next question: when a tank gets hit, what exactly is it that knocks it out, assuming the engine isn't hit? Shell fragments and spall cooking off your ammunition is an obvious risk, but if your rounds are wet racked or outside the crew compartment, how much danger is the crew in from overpressure or spalling? Is a significant amount of heart actually transferring into the crew compartment? Curious about both WW2 era tanks and modern ones, if people happen to know. I've linked this before, but in case anyone missed it, this might be relevant to the discussion (enable captions to see my shoddy English translation): https://www.youtube.com/watch?v=MiWCpIJ5dBw
|
|
#
?
Aug 19, 2014 11:07
|
|
|
JaucheCharly posted:That is spectacularly stupid. Years in tech support tell that it can get alot worse. These people are allowed to operate cars. And BREED!
|
|
#
?
Aug 19, 2014 12:19
|
|
HEY GAL posted:So, this weekend I met a guy who also does Napoleonic reenactment (he invited me to Waterloo next year, it's the anniversary and it's gonna own). He and his bros portray the Black Brunswickers--all black, death's head on their shakoes, etc, and he said a tourist told him once "I didn't know they also had the SS in the Middle Ages."  "Dammit, I bet the pirate guys don't have to put up with this!" "Which one of you Johnny Depp?" "All of us." (The correct reply).I'd love to read more odd things seen/heard in reinacment now.
|
|
|
#
?
Aug 19, 2014 14:38
|
|
|
|
| # ? May 28, 2024 22:36 |
|
|
I shall oblige! Remember my friend who is into pretending to be a viking? For extra money during college he used to work in Dublinia over the summers with some of the other guys. One year he had a bunch of American Christians turn up with bibles and try to convert them. Apparently the environment was not enough of a giveaway. They reacted about as well as you'd expect vikings to.
|
|
#
?
Aug 19, 2014 15:11
|
|