The Macabees
03-12-2005, 08:13
[Copyring on Images: More likely than not they were drawn by Mekugi.]
[Disclaimer: This is subject to be updated, frequently. If you want your armour to be added on to this, just request it and I'll evaluate it.]
Preface
The idea behind this guide was to alleviate some of the problems people were having in designing tanks, and then get rid of some of the misconceptions with new armour technology, and even some misunderstanding, while some others are even exagerating. So, it can be said that I'm attempting to establish the authoritive guide on armour and the designing of armour. With that said perhaps I should break up this essay into chunks here in the preface, perhaps briefly outlining exactly what I will be talking about. Before I actually dwelve into that, however, this guide does borrow lightly from Clan Smoke Jaguar's older guide, Some Things You Should Know About Tanks (http://forums2.jolt.co.uk/showthread.php?t=288671[/url), which is extremely well done within itself, if only a bit outdated and a bit vague when it comes to specific information on certain aspects of the tank.
Nonetheless, this avoid having this thread branded as a basic reiteration of the older guide I should really clear up on what this guide attempts to establish. In the most general terminology this guide is here to expand on what CSJ already laid down in his own article. It is to say, it's an expansion with a bit of a better developed basis, although it's no better than his. In fact, the perceptive reader should most likely open both and read them both if he/she truly wants to get a full understanding on armour, technology and design. In terms of armour this guide should provide specific values for real life and NationStates specific armour, while it should also expand on how exactly certain armour types work. This guide should also prove valuable in the designing of a specific round, especially if you're working with armour piercing fin stabalized descarding sabots. Finally, it should specify on other aspects as well, including main armament, secondary armament, sensor systems, extraneous systems including shortstop, and finally, pricing and procurement. All in all, this should be a celebrated expansion to CSJ's guide.
For some order of sequence I'll be beginning with the armour, providing with a general explenation of armour on tank, and then going into specifics on certain types of armour, including ceramic composites and reactive armours. Then I'll move into the area of the main gun and tank rounds in existance and I'll provide certain information which should prove invaluable for the designing of newer tank guns and better tank rounds. Following the main gun I'll go into what I see as a rising pit of extraneous machinery, the engine, and to for the sake of context I'll then explain sensor systems and defensive systems on tanks and why some systems are just not worth putting on individual pieces of armour. Continuing, I should dabble into weight and total ground pressure and finally into pricing. To end it all I'll describe methods of defeating modern armour, anit-tank vehicles and a brief overview of what awaits in the future.
To end this, I suggest you criticisize, appraise, or do whatever you want to do with this thread. Hopefully, this proves somewhat valuable to other NationStates Role Players. In terms of credibilty the information here was painstakingly researched and there should be rather low possiblities of inaccuracies, although any corrections are very welcomed. With that said, thank you for reading.
Glossary
APFSDS: Armor Piercing, Fin Stabilized, Discarding Sabot; a type of anti-tank rounds that defeat an armored target by means of kinetic energy of a subcaliber projectile placed inside of a sheath, or 'sabot', that is discarded in flight. Russian APFSDS rounds have a designation 3BM[number].
APS: Active Protection System; a system that automatically intercepts threats that attack the protected object in the immediate vicinity of the object. Essentially the APS is a super-close-in system of "anti-missile defense" that creates an "active" zone of protection at a safe distance around the objects.
ATGM: Anti-Tank Guided Missile
CE: Chemical Energy
EOCMDAS: Electro-Optical Counter-Measures Defensive Aids Suite; a system that interferes with the operation of guided munitions and FCS, degrading their effectiveness
ERA: Explosive Reactive Armor; an applique armor that consists of a HE layer between two metal slabs. When a HEAT round strikes a ERA package, HE layer detonates inducing a spin of metal slabs which causes HEAT jet to collapse or lose penetrating power. Modern Russian ERA is also effective against APFSDS rounds.
FCS: Fire and control system.a complex of targeting, rangefinding, fire solution computation, and sensor equipment that enhances the fire accuracy, especially at long ranges.
HBT: Heavy Battle Tank.
HE: High Explosive
HEAT: High Explosive Anti-Tank; a type of anti-tank rounds that defeat an armored target by means of a hyper-velocity jet that is formed when a charge consisting of a concave metal hemisphere or cone (known as a liner) backed by a high explosive detonates. Russian HEAT projectiles have a designation 3BK[number].
HEF: High Explosive Fragmentation; a type of rounds that contains a HE charge together with preformed hitting elements or a controlled fragmentation layer, increasing its anti-personel effectiveness. Russian tank-carried HEF projectiles have a designation 3OF[number].
KE: Kinetic Energy; most likely referring to penetrators - most likely the APFSDS round or anti-tank guided missiles that work on similar concepts.
LBT: Light Battle Tank.
MBT: Main Battle Tank.
NBC: Nuclear, Biological, Chemical; the use of these types of weapons on a battlefield, or tanks equipment designed to protect the crew from the effects of these weapons.
RHA: Rolled Homogeneous Armor; a process of armor manufacturing that ensures its uniformity and enhances resistance to penetration. Often used in the same sense as RHAe.
RHAe: Rolled Homogeneous Armor Equivalent; an equivalent RHA thickness of a given armor package against a given type of threats in terms of penetration resistance. Modern armor packages may be several times more efficient against certain threats than RHA of the same thickness.
Armour
As far as I've witnessed armour and value has been the area of greatest misconception, including the eventual RHAe values of said armour. For example, I've seen tanks of pure chobham claim values that exceed one thousand five hundred millimeters which would be, simply said, preposterous, although technically possible. Regardless, this should clear a few up on different types of armour, how they work, and what exact rating they get. This should also compare different sources and different points of view on what exact role they fit into and how effective they are. First, perhaps I should explain the concept of rolled homogenous armour equivalent [RHAe]. RHAe, most of the time referred to as RHA on NationStates since the two are technically interchangeable, referres to the protection in terms of actual steel thickness. For example, 400mm RHAe would imply that the protection of said armour is the equivalent to 400mm of actual steel. This doesn't imply that the armour is actually 400mm thick, which is the purpose of RHAe - it is to say, a 50mm plate of chobham could actually render around 125mm versus kinetic energy penetrators.
There have been certain developements in tank armour since the Second World War which some can refer to as the 'awakening' of the tank as a truly powerful weapon, although technically the 'awakening' had existed since the early 1930s in the French and Russian militaries. But that is besides the point. Early armour, including armour during the Second World War was made principally of hardened steel, which even today remains a viable force with certain design features that make it stronger, but in general newer armour composites and other designs have replaced steel on a wide basis because of better ratings.
Chobham: Chobham was designed by the British and although the exact composition remains relatively unknown there are certain theories, and a list of possible ingredients. In the most general terms, however, it's ceramic between two steel plates woven around a titanium matrix [most commonly], with depleted uranium rods or modules allowing for somewhat more rigidity and better resistance. When defeating high explosive anti-tank warheads chobham works similar to a reactive armour by having the ceramic plate collapse on impact creating a mass of dust which slows the jet of molten flame when it breaks through the layer of steel. Again kinetic energy, which British chobham, or Dorchester armour, has the best rating of all armours, chobham mostly works by applying density and electro-magnetic force against incoming rounds. Evidently, it works quite well.
I really couldn't give an accurate ratio on chobham, and I've seen claims as high as 1:5 [real thickness to rolled homogenous armour equivalent], but personally I see this as too high and if the rumours are true then you might as well believe that the Indian Arjun tank has the best armour rating of all main battle tanks. Therefore, until I can research a bit more I strongly suggest you stick with the good ratio of 1:2.5, and if you're using a more advance [namely your own] version of chobham then I would suggest 1:3 - all of these of which are versus KE. When it comes to defending against HEAT I would suggest a ratio of 1:4.2 telling from the mass of the armour with the ratio of 1:2.5 against KE rounds.
Cermet: Cermet is even more secretive than chobham armour and I would suspect that it works in a similar fashion. In a recent pdf I found an article on non-uranium cermet variations which seem to imply that there are variations of cermet with depleted uranium. Nonetheless, cermet in its simplistic form is a different ceramic armour and so that would mean that cermet works along the same principles of chobham. The prototype LeClerc released in the early 1980s was said to have a ratio of 1:2, with roughly the same armoured mass as the Chieftan, meaning that LeClerc main battle tank has an armoured mass of four hundred millimeters with a rolled homogenous armour value of eight hundred.
Explosive Reactive Armour: Originally ERA was designed to counter HEAT warheads and it was invented in the 1960s by Norwegian engineer Dr. Manfred Held who designed a pack of explosives between two steel plates, which to this day remains known as ERA, despite certain advances, including insulation between bricks and such. The idea is similar, but more drastic, to that of chobham. In effect, a round would hit the steel and the explosion would counter act the HEAT warhead by breaking up the molten jet. Those primarilly known to counter HEAT are known today as 'light ERA'. Since the advances in sabot technology ERA has been modified into a 'heavy ERA' highlighted by Kontakt-5, the most advance type of ERA to date. Unfortunately ERA still doesn't reap what chobham does as Kontakt-5 is rated at three hundred millimeters versus KE, and in effect, ERA bricks are heavy.
However, these optimum reaps are specifically for 60 degree angle sloping. So obviously the ratings decrease depending on where the bricks are placed, including the near verticle rear armour and the slightly sloped side armour. Sixty degrees remains true for almost all explicitely explosive reactive armours including the next, SLERA.
On the negative note, there have been reports that heavy ERA also does damage to the vehicle itself although Kiev.ru doesn't claim anything. Nonetheless, it should be taken into mind. A very easy way of solving this a tad would be to insulate the rear of the brick as well as the area between bricks that prevent neighboring bricks from setting each other off. It should work relatively well, although it will add weight, obviously.
Self-Limiting Explosive Reactive Armour: In all actuality SLERA is a dumbed down version of ERA, so there's really no reason to believe that SLERA would render better than ERA against either KE or CE [HEAT]. In fact, maximum ratings I would suggest for SLERA remain at 200mm vs. KE and about 500mm vs. CE. Regardless, SLERA does have its advantanges, including ample protection for infantry fighting vehicles while it's relatively safer than ERA when infantry are sorrounding it. But with all other technolodies in armour I really don't see the advantage of using SLERA, as it's inneffective for most of NS grade weaponry, including anti-tank guided missiles, and it is still rather heavy.
Non-Energetic Reactive Armour and Non-Explosive Reactive Armour: These are NERA and NxRA respectively. NERA, unfortunately, has insubstantial claims against KE, with its rating against CE 400mm RHAe maximum, and even that's a stretch. It's counterpart, NxRA, the ultimate infantry friendly Russian armour scheme has about 150mm vs. KE RHAe and 400mm vs. CE RHAe. The difference between the two seems to be that NxRA is a slightly more volatile reactive armour than NERA, despite the two names. Personally, I wouldn't suggest it for use on an armour vehicle, especially NxRA which I see a lot, since there's still a slight reaction, which will disrupt covering layers of armour unfortunately.
Modular Expandable Armour System: MEXAS is used widely by the Germans and a published paper gives very good ratings for the armour. Unfortunately, attempts to establish credibility of high ratings versus KE failed and it seems that the protection versus KE is rather insubstantial. In terms of effectivity versus CE it seems completely the opposite. The paper claims that at 15 degrees MEXAS is just as effective versus CE as ERA. In fact, it claims that at 7mm of actual thickness it has a value of 250mm, or 1:36. The system seems to work similar as to NxRA but with better results, including a bulging chemical reaction which seems to break up the molten jet coming from a heat warhead. A much safer, and much more conventional claim, however, remains at around 1:20, and just like NxRA, MEXAS absolutely cannot be put underneath other layers of armour because it will disrupt and crack the above layers. But, on a main battle tank, what's the use of having a layer of MEXAS first?
Enhanced Appliqué Armor Kit: EAAK is a French design used on several newer APCs and is wholy an appliqué armour, meaning it can be added by means of putting slabs on it on rails if your tank includes them to handle ERA add-ons, which most do if the ERA is not already included on the tank. When it comes to protection versus CE, which is all it really protects against, the ratio is 1:10 at 45 degrees. What advantages does this hold over MEXAS? Well, for one, it's modular, meaning it's cheaper. Second, it can be applied and taken off at will, and if damaged can be re-applied. In other words it's logistics friendly. Third, it's most likely lighter as well.
Captive Explosive Reactive Armour: CERA was invented by Mekugi and first released to the IADF for investigation. CERA has proved to be a more successful version of SLERA. It works through hexagonal bricks covered with a film of charged metal. Within the hexagon is an explosive propelled by a piston, and so when the round hits the piston sets off the charge and pushed it through the hexagon at ungodly velocities. The latest version, third generation CERA, offers a redesigned rim, increasing gas pressure, and ironically, also increasing safety. It offers 25mm versus KE and 700mm to 1400mm [theoritical] vs. CE.
http://img.photobucket.com/albums/v203/jay3135/Hardware/ceraa.png
http://img.photobucket.com/albums/v203/jay3135/Hardware/cerab.png
So, there you have it. Technically you could include reactive armour, insane levels of ceramic armour and modular armour, but please don't. Realistically, a tank with weight levels underneath 110 tons should have .7 meters or less of actual thickness of the armour. The Abrams, at 68.7 tons, has 384mm of actual thickness in the armour according to the RHAe ratios, while the LeClerc has 400mm. Although armour is not all when it comes to weight, as opposed to the design of certain components and relatively volume in the tank, it is a big part and so designers should be extremely careful when designing the armour on their tanks.
In terms of how much should be slapped on the side and rear., well, the best I can offer you is the following. The glacis armour should have a real thickness roughly 60 to 70% of that of the turret armour. The side armour should have roughly 50% the turret armour while the rear armour should, at most, have 30% of the turret armour. The lower frontal armour should have around 65% of the turret armour ratings.
The Main Gun
The principle armament of the main battle tank will always remain the main gun as long as main battle tanks remain main battle tanks. In the real world there are four main bore sizes including, 105mm and 120mm [the United States], 122mm [some Europeans] and 125mm [Warsaw Pact]. Speaking through generalities, the bigger the bore the longer the range and the more penetration achieved, and in the same way, the longer the gun the same remains true. Unfortunately, this isn't always true. There's a certain threshold limit where the mass of the round is maximized when put into context with the velocity. Warsaw Pact and even modern Russian sabot rounds are known for their innacuracy and their lack of power when lined up against the American 'silver bullet'. This can be attributed to the fact that although the American round is lighter it has a greater velocity, so it achieves more force. Although I can't tell you the exact measurement of mass of the Russian round let's take 7.6kg at 1361m/s against 9kg at 1020m/s^2. So, using a basic force equation [F=ma] you get 10342N[ewtons] and 9180, respectively. Although this doesn't mean that the heavier the worse, a tank designer should really take into consideration the mass of the round and the velocity it achieves and compare this against other permutations. Although it is a bit of work, and to some rather pointless, the round really does offer an advantage in the battlefield.
When it comes to conventional guns there are two principal versions, the smooth bore and the rifled bore. The rifled bore gun, equipped on the Challenger II, increases the lethal range of the round, and it remains the same even on small arms. A rifled bore barrel on a rifle will have a higher lethal range than a smoothbore; an example of a smoothbore small arm is a common shotgun. Rifled bore guns also have the ability of firing HESH rounds, which disputedly smooth bores either can't, or can't so well. Probably the largest issue is that under wartime conditions a rifle bore gun would most likely have to be replaced every 600 or so rounds, which is considerably less than a smooth bore gun. There are also claims that a smoothbore rifle gun has greater accuracy firing APFSDS, as opposed to the rifle bore, and the smooth bore, of course, can fire ATGMs.
Newer advances in gun technology are lead by the electro-thermal chemical gun. Basically, the ETC gun replaces the standard propellant with a surge of electricity that fires a plasma which in turns sets off a chemical propellant. The result is a greater initial, and thus final, velocity for the round. In terms of results Rhinemetal claims a complete 100% increase in the effectivity of the conventional Abrams 120mm round by 2017, although 2020 is a more rounded and more accurate date. Nonetheless, through NationStates perceptions ETC is an early post-modern technology design so you should have no problem using it. However, be wary of the bore in use with the weight of the tank. A tank that weighs somewhere around 70 to 80 tons should have no problem being equipped with a 120mm ETC. To upgun it to a 135mm I really suggest a weight of at least 85 tons, while a 140mm ETC should only be used on a tank of 90 tons and up.
Other upcoming designs include electro-magnetic rifling. There are two types of rifling which you should be aware of, coil and rail. The coil and rail guns work on similar principle although in the coil gun, which is scheduled to be released as a working gun by 2030 [although, again, through etiquette, a common mainstream PMT attribute] and works through a semi or superconductive material woven in the shape of a coil which rifles the gun [as opposed to being a smooth or rifled bore]. In effect, the shell spins in the direction of the electricity running through the coils. There have been grievances that there is a cap in the length of a possible coil gun, which has its merits, and is probably true. The problem is, when the coil rifling gets too long there are threats that the round will actually slow in the rotations meaning the velocity it leaves the barrel at is actually rather slow as compared to a standard gun, or an ETC gun.
Rail guns, on the other hand, use two parallel rails, again with semi or superconducters, although obviously the latter is the better choice and a series of magnets. Using Lorentz' Force and Gauss' Law the round should technically never touch the rails and using superconducters there's no resistance against the electricity, meaning that the only problem with rail guns is the repulsion between the rails which are different charges. Apparently, the U.S. Navy has solved it, detailed in a pdf I read a whilea go which introduces a titanium alloy as the new superconducter in use with the navy and apparently one of the options for the DDX variant with the rail gun. However, there's also a length cap on the rail gun.
Coil guns get less power and are more believable when use on a MBT, and furthermore offer less questions on maintenance and the such although the rifling should probably be replaced after every one hundred or so rounds. It takes a 600 volt battery to power a 120mm ETC gun, so logically it should take around 900 volts to power both an ETC gun and a coil gun, and with increased bore perhaps up to 1000 volts, which is over three times the amount of electricity supplied to European households. But, unlike some more conventional thinkers, I really don't think there are major obstacles prohibiting the early introduction of coil guns into NationStates armour.
Another technique of increasing both the penetration and the range is to use a magnum round. Now, I really can't specify if the magnum round could work in a pure rail gun, but it should be able to do just fine in electro-magnetic rifling since EM rifling on tanks is a bit of a deviation on what a coil gun truly entails. Regardless, magnum rounds have always been used to achieve high velocities, and coined the term high velocity projectile [HVP] guns. The topic was begun on this very thread on the second page and a series of inquiries enlightened me on the true nature of high velocity projectiles, although a few of the earlier things I knew stay true. The Israeli HVP is a stub gun, meaning it has rather short calibre length for its bore size, much like early German tanks did, but this doesn't necessarilly mean that the gun has to stay a stub. Most of the following information is based on what Strathdonia told me, but in effect, a longer barrel, and wider barrel as well, would increase volume required for the propellant to burn properly. In other words, the more time the round has for the propellant to properly ignite the more powerful the round, understandably. Unfortunately, not all is a bed of roses when it comes to using magnum rounds on a tank gun. Barrel wear is absolutely horrendous, dropping the roundabout rating of one thousand rounds per barrel to a mere six hundred rounds per barrel. If you're using an electro-thermal chemical gun with electromagnetic rifling, the wear on the rifling should increase respectively, meaning you would gain even more logistical issues - replacing the barrel, say, every five hundred rounds, or a 50% drop in logistical effectivity. Now, using the example of Hindustani tanks [not real life India, mind you], they don't expect their Sheridan upgrades to really survive that long, so a HPV gun really isn't an issue to them when it comes to logistics - they'll probaby have to replace the whole tank, period.
When it comes to the range of guns a maximum range will always stay withing five thousand to seven thousand meters, like some claims give. In fact, a Tiger was reported knocking out a T-34 at six thousand meters. These claims are luck; for any gun system the optimum maximum range would be at under three thousand meters, with full penetration at under eight hundred meters. Believe it or not, your round loses a lot of energy the farther it goes.
There are a multitude of type of rounds, but they all classify under two principal genres. That is CE and KE. KE stands for kinetic energy and denotes a round that relies on pure momentum, force, and density for penetration. In other words, the round does not rely on an explosive. CE stans for chemical energy, or something which uses an explosive, since explosives are chemically composed. CEs range from HEAT [High Explosive Anti-Tank] to HE [High Explosive] warheads. For tank to tank warfare, KEs on standard get better penetration figures, while CEs are better for man portable weapons since they're lighter and produce far lower recoil [slower muzzle velocity necessary]. Tanks normally carry both, one for tank to tank warfare, and one for anti-infantry warfare. The ratio is up to you and the type of combat you expect.
General Formulas:
Velocity(at range r) = Vmuzzle / (1 + k*r*D^2 / M)
k = pi / 8 * airdensity *; or just use .305
D = sabot diamter
M = mass of the round
r = range
Vr [velocity at the range the round is hitting]
Vmuzzle
mpV2/d3=C(t/d)n
mp = mass of projectile in kg
d = diameter of projectile in mm
V = velocity of projectile at impact in m/s
t = thickness of armor perforated in mm
C = 'constant' that has a varying value, increases as L:d ratio increases [suggest value is 11]
n = 'constant' that has a varying value, generally between 1 & 2, decreases as L:d ratio increases [suggest value 1.33]
Secondary Armament
There's not much to say about secondary armaments. The nature of secondary armaments has seemed to change throughout the years, and while the Germans during the Second World War seemed to focus on machineguns, modern tanks have included a host of other weapons. In general the tank has a coaxial machinegun which is normally mounted right beside the main gun since it follows exactly where the turret points at. These normally measure 7.62mm [NATO round]. Sometimes there's a top gun, like on the M1A2 Abrams which can double as an anti-aircraft gun against helicopters that range from 7.62mm to 12.7mm [NATO]. Some tanks include mortars and even grenade launchers for light suppression and smoke generation for tactical situations. Some tanks even include self-invented systems like Mekugi's SSDs.
http://img526.imageshack.us/img526/2315/ssd6qj.png
The only thing I can think about right now is the firing mechanism of machine guns. The Germans designed it so that it would be a pulley system which fired the machine gun. Others have developed their own systems - I strongly suggest you consider the German method; I've always heard only positive arguments towards it.
When it comes to adding ATGM and SAM launchers, it's feasible. The question is, is it worth mountaing on an MBT? The price should drive up considerably, and it would be just as worth it to mount it on a seperate, cheaper, lighter vehicle, would it not? Regardless, in the end, the tank is yours and prices should be explained a bit better somewhere below.
Engines
When it comes to engines there are two principal types of engines widely used and considered 'conventional' on NationStates. These include the standard turbine/piston engine used by Real Life armour and the newer, less understood, quasiturbine engine. The latter, although truly a future technology [on NS, PMT], is considered a conceivable attribute on a tank and is largely permitted by most NSers. There are a few things to know about each one however, first starting with the conventional engine.
When it comes to the conventional engine the most important aspect is the type of fuel in use. There are three main variants of fuel: Gasoline, Diesel, and Biodiesel. Gasoline was used and is still used on Abrams tanks, although the Army and the Marines are planning to replace all gasoline engines with diesel engines after an entire tank division had to stop and wait for fuel in Operation Desert Storm, allowing an entire concentration of Iraqi soldiers to escape the encirclement during the opening days of the operation. It is to say, gasoline is a relatively bad way to go. Gasoline renders less torque, which is extremely important on a tank, and expends faster. Diesel achieves greater torque, expends slower, but suffers from an increased cost because of the refinement process. Biodiesel expands on the advantages of diesel but is also relatively more expensive, although it is a cleaner fuel. When it comes to conventional engines diesel is the most widely used, with biodiesel coming a close second.
There are few problems with the quasiturbine engine apart from the fact that it has never been tested before on an actual vehicle, heavy or light. The biggest problem that can be seen today is the fact that the engine, now wrought out of ironcast, has a tendency to expand while in use because of the heat. Ergo, it would also have poor ratings against fatigue, creep and resistance. Nevertheless, with modern superalloys, especially those used on aircraft engines and even alloys used in bridging, the problem should be slightly alleviated. Indeed, the best alloy to look for is the one that is accustomed to expansion, and therefore has more resistance to it. When all is taken into mind a quasiturbine really is not a bad choice. In terms of fuel you have the same line up; make a decision for yourself.
Sensors, Defenses and Cost Effectiveness
Now, here is where the tricky part is. In terms of sensors all keep it relatively the same; surface search radar, lidar and ladar, with good ol' fashion infra-red seekers and rangefinders. So, it's not really the sensor suits were tanks start to deviate from the original purpose of the tank, it's the defense mechanisms. For example, let's take shortstop. Most tanks on NS use shortstop. For what? The purpose of shortstop is to set off the fuse of incoming artillery shells before they hit their intended height, and thus rendering them harmless. Unfortunately, shortstop is an expensive system, but it covers a wide area. In all reality shortstop was meant to be used on inexpensive reconnaissance vehicles, like the Humvee, not on tanks. In fact, putting a shortstop electronics suit on every tank capitalizes on how not cost effective that tank is - and in fact, shortstop should increase the price of each tank by a good two million USD.
I won't get into every sensor and defense suit there is, but I think you get the picture. In other words, when you're designing your tank take each system, research it, and evaluate it. The task at hand is to create a cost effective tank - not a vehicle that has so much on it that if it gets knocked out you go bankrupt. You should always look for better ways of employing something. Could you not employ shortstop on a smaller, cheaper, vehicle that can travel with brigades of armour? Even squad level cars? Would not that be cheaper than to employ it on each individual tank? It's that level of thinking which will achieve you a better tank.
In short, what makes a tank good is how much it gets per shot; is the tank worth building? For example, you can take a 27 million dollar tank, which [i]does exist on NS, and compare it to the Abrams, which costs maximum 6 million. In essense, to get its cost effective worth it would take the first tank five kills. Although the Abrams is not state of the art when compared to other tanks on NationStates, a round in the rear at the hands of the conventional 120mm gun would most likely penetrate any tank on NationStates to date. The most likely case is that five Abrams could very well take on that 27 million tank, despite its shortstop, advance armour composite and bigger gun. So, the nation that fields the first tank would go bankrupt, while the nation that fielded the cheaper tank would get off at a more cost effective war with cheaper technology. So, when you're putting in your super advance surface to air missile, think to yourself; do I really need this?
Anti-Tank Systems
As tanks get more expensive anti-tank systems also get more expensive. By all means and purposes the stereotypical anti-tank vehicle, which is turretless, is outdated and obsolete. Nonetheless, there are still types of warheads that will render pretty well against armour including larger HEAT, tandem warheads, LOSATs and shoulder fired fire and forget anti-tank missiles that work similar to the LOSAT [the Javeline].
HEAT has met it's match when it comes to armour, but against certain armours like ERA and chobham the wider the HEAT projectile the better effect it has. Naturally, there's a cap, but HEAT has not been totally phased out and it will be a while before it is. HEAT is still a viable option, especially for a small nation that can't afford any of the more expensive ordnance.
In terms of missiles LOSATs mounted on cheap and light reconnaissance vehicles have actually proved quite capable of engaging and defeating modern battle tanks. In fact, LOSATs offer a cost effective method at destroying a sixteen million dollar piece of equipment at the cost of around two million USD. So, main battle tanks still do not rule the battlefield, and most likely never will. I won't get much into anti-tank weapons here because they belong in another discussion or thread, but MBTs are not an end all, be all weapon. Combined arms young grasshopper!
Conclusions
When putting the tank together you should look less to modern application and more towards your application. In effect, model the tank to serve your military best, and to do this you should analyze your own battles and your own strategy. In fact, there is no 'perfect balance'. To all which meets their needs, as Marx one said. Although I am no Communist within the context of tanks, and without including the context of the statement, it makes sense. Your focus could be firepower, your focus could be velocity; it all depends on how you fight in your own army. For example, the Soviet Union focused on cheap but effective tanks, and in the end they fielded up to tens of thousands of their tanks, despite quite obvious disadvantages, although when the T-62 came out it did sent some NATO experts jumping around. Regardless, I reiterate, the tank should be crafted around the needs of your nation; not the other guy's nation. You know best what you need.
This guide is subject to expand and change. However, good luck with future tank designs!
[Disclaimer: This is subject to be updated, frequently. If you want your armour to be added on to this, just request it and I'll evaluate it.]
Preface
The idea behind this guide was to alleviate some of the problems people were having in designing tanks, and then get rid of some of the misconceptions with new armour technology, and even some misunderstanding, while some others are even exagerating. So, it can be said that I'm attempting to establish the authoritive guide on armour and the designing of armour. With that said perhaps I should break up this essay into chunks here in the preface, perhaps briefly outlining exactly what I will be talking about. Before I actually dwelve into that, however, this guide does borrow lightly from Clan Smoke Jaguar's older guide, Some Things You Should Know About Tanks (http://forums2.jolt.co.uk/showthread.php?t=288671[/url), which is extremely well done within itself, if only a bit outdated and a bit vague when it comes to specific information on certain aspects of the tank.
Nonetheless, this avoid having this thread branded as a basic reiteration of the older guide I should really clear up on what this guide attempts to establish. In the most general terminology this guide is here to expand on what CSJ already laid down in his own article. It is to say, it's an expansion with a bit of a better developed basis, although it's no better than his. In fact, the perceptive reader should most likely open both and read them both if he/she truly wants to get a full understanding on armour, technology and design. In terms of armour this guide should provide specific values for real life and NationStates specific armour, while it should also expand on how exactly certain armour types work. This guide should also prove valuable in the designing of a specific round, especially if you're working with armour piercing fin stabalized descarding sabots. Finally, it should specify on other aspects as well, including main armament, secondary armament, sensor systems, extraneous systems including shortstop, and finally, pricing and procurement. All in all, this should be a celebrated expansion to CSJ's guide.
For some order of sequence I'll be beginning with the armour, providing with a general explenation of armour on tank, and then going into specifics on certain types of armour, including ceramic composites and reactive armours. Then I'll move into the area of the main gun and tank rounds in existance and I'll provide certain information which should prove invaluable for the designing of newer tank guns and better tank rounds. Following the main gun I'll go into what I see as a rising pit of extraneous machinery, the engine, and to for the sake of context I'll then explain sensor systems and defensive systems on tanks and why some systems are just not worth putting on individual pieces of armour. Continuing, I should dabble into weight and total ground pressure and finally into pricing. To end it all I'll describe methods of defeating modern armour, anit-tank vehicles and a brief overview of what awaits in the future.
To end this, I suggest you criticisize, appraise, or do whatever you want to do with this thread. Hopefully, this proves somewhat valuable to other NationStates Role Players. In terms of credibilty the information here was painstakingly researched and there should be rather low possiblities of inaccuracies, although any corrections are very welcomed. With that said, thank you for reading.
Glossary
APFSDS: Armor Piercing, Fin Stabilized, Discarding Sabot; a type of anti-tank rounds that defeat an armored target by means of kinetic energy of a subcaliber projectile placed inside of a sheath, or 'sabot', that is discarded in flight. Russian APFSDS rounds have a designation 3BM[number].
APS: Active Protection System; a system that automatically intercepts threats that attack the protected object in the immediate vicinity of the object. Essentially the APS is a super-close-in system of "anti-missile defense" that creates an "active" zone of protection at a safe distance around the objects.
ATGM: Anti-Tank Guided Missile
CE: Chemical Energy
EOCMDAS: Electro-Optical Counter-Measures Defensive Aids Suite; a system that interferes with the operation of guided munitions and FCS, degrading their effectiveness
ERA: Explosive Reactive Armor; an applique armor that consists of a HE layer between two metal slabs. When a HEAT round strikes a ERA package, HE layer detonates inducing a spin of metal slabs which causes HEAT jet to collapse or lose penetrating power. Modern Russian ERA is also effective against APFSDS rounds.
FCS: Fire and control system.a complex of targeting, rangefinding, fire solution computation, and sensor equipment that enhances the fire accuracy, especially at long ranges.
HBT: Heavy Battle Tank.
HE: High Explosive
HEAT: High Explosive Anti-Tank; a type of anti-tank rounds that defeat an armored target by means of a hyper-velocity jet that is formed when a charge consisting of a concave metal hemisphere or cone (known as a liner) backed by a high explosive detonates. Russian HEAT projectiles have a designation 3BK[number].
HEF: High Explosive Fragmentation; a type of rounds that contains a HE charge together with preformed hitting elements or a controlled fragmentation layer, increasing its anti-personel effectiveness. Russian tank-carried HEF projectiles have a designation 3OF[number].
KE: Kinetic Energy; most likely referring to penetrators - most likely the APFSDS round or anti-tank guided missiles that work on similar concepts.
LBT: Light Battle Tank.
MBT: Main Battle Tank.
NBC: Nuclear, Biological, Chemical; the use of these types of weapons on a battlefield, or tanks equipment designed to protect the crew from the effects of these weapons.
RHA: Rolled Homogeneous Armor; a process of armor manufacturing that ensures its uniformity and enhances resistance to penetration. Often used in the same sense as RHAe.
RHAe: Rolled Homogeneous Armor Equivalent; an equivalent RHA thickness of a given armor package against a given type of threats in terms of penetration resistance. Modern armor packages may be several times more efficient against certain threats than RHA of the same thickness.
Armour
As far as I've witnessed armour and value has been the area of greatest misconception, including the eventual RHAe values of said armour. For example, I've seen tanks of pure chobham claim values that exceed one thousand five hundred millimeters which would be, simply said, preposterous, although technically possible. Regardless, this should clear a few up on different types of armour, how they work, and what exact rating they get. This should also compare different sources and different points of view on what exact role they fit into and how effective they are. First, perhaps I should explain the concept of rolled homogenous armour equivalent [RHAe]. RHAe, most of the time referred to as RHA on NationStates since the two are technically interchangeable, referres to the protection in terms of actual steel thickness. For example, 400mm RHAe would imply that the protection of said armour is the equivalent to 400mm of actual steel. This doesn't imply that the armour is actually 400mm thick, which is the purpose of RHAe - it is to say, a 50mm plate of chobham could actually render around 125mm versus kinetic energy penetrators.
There have been certain developements in tank armour since the Second World War which some can refer to as the 'awakening' of the tank as a truly powerful weapon, although technically the 'awakening' had existed since the early 1930s in the French and Russian militaries. But that is besides the point. Early armour, including armour during the Second World War was made principally of hardened steel, which even today remains a viable force with certain design features that make it stronger, but in general newer armour composites and other designs have replaced steel on a wide basis because of better ratings.
Chobham: Chobham was designed by the British and although the exact composition remains relatively unknown there are certain theories, and a list of possible ingredients. In the most general terms, however, it's ceramic between two steel plates woven around a titanium matrix [most commonly], with depleted uranium rods or modules allowing for somewhat more rigidity and better resistance. When defeating high explosive anti-tank warheads chobham works similar to a reactive armour by having the ceramic plate collapse on impact creating a mass of dust which slows the jet of molten flame when it breaks through the layer of steel. Again kinetic energy, which British chobham, or Dorchester armour, has the best rating of all armours, chobham mostly works by applying density and electro-magnetic force against incoming rounds. Evidently, it works quite well.
I really couldn't give an accurate ratio on chobham, and I've seen claims as high as 1:5 [real thickness to rolled homogenous armour equivalent], but personally I see this as too high and if the rumours are true then you might as well believe that the Indian Arjun tank has the best armour rating of all main battle tanks. Therefore, until I can research a bit more I strongly suggest you stick with the good ratio of 1:2.5, and if you're using a more advance [namely your own] version of chobham then I would suggest 1:3 - all of these of which are versus KE. When it comes to defending against HEAT I would suggest a ratio of 1:4.2 telling from the mass of the armour with the ratio of 1:2.5 against KE rounds.
Cermet: Cermet is even more secretive than chobham armour and I would suspect that it works in a similar fashion. In a recent pdf I found an article on non-uranium cermet variations which seem to imply that there are variations of cermet with depleted uranium. Nonetheless, cermet in its simplistic form is a different ceramic armour and so that would mean that cermet works along the same principles of chobham. The prototype LeClerc released in the early 1980s was said to have a ratio of 1:2, with roughly the same armoured mass as the Chieftan, meaning that LeClerc main battle tank has an armoured mass of four hundred millimeters with a rolled homogenous armour value of eight hundred.
Explosive Reactive Armour: Originally ERA was designed to counter HEAT warheads and it was invented in the 1960s by Norwegian engineer Dr. Manfred Held who designed a pack of explosives between two steel plates, which to this day remains known as ERA, despite certain advances, including insulation between bricks and such. The idea is similar, but more drastic, to that of chobham. In effect, a round would hit the steel and the explosion would counter act the HEAT warhead by breaking up the molten jet. Those primarilly known to counter HEAT are known today as 'light ERA'. Since the advances in sabot technology ERA has been modified into a 'heavy ERA' highlighted by Kontakt-5, the most advance type of ERA to date. Unfortunately ERA still doesn't reap what chobham does as Kontakt-5 is rated at three hundred millimeters versus KE, and in effect, ERA bricks are heavy.
However, these optimum reaps are specifically for 60 degree angle sloping. So obviously the ratings decrease depending on where the bricks are placed, including the near verticle rear armour and the slightly sloped side armour. Sixty degrees remains true for almost all explicitely explosive reactive armours including the next, SLERA.
On the negative note, there have been reports that heavy ERA also does damage to the vehicle itself although Kiev.ru doesn't claim anything. Nonetheless, it should be taken into mind. A very easy way of solving this a tad would be to insulate the rear of the brick as well as the area between bricks that prevent neighboring bricks from setting each other off. It should work relatively well, although it will add weight, obviously.
Self-Limiting Explosive Reactive Armour: In all actuality SLERA is a dumbed down version of ERA, so there's really no reason to believe that SLERA would render better than ERA against either KE or CE [HEAT]. In fact, maximum ratings I would suggest for SLERA remain at 200mm vs. KE and about 500mm vs. CE. Regardless, SLERA does have its advantanges, including ample protection for infantry fighting vehicles while it's relatively safer than ERA when infantry are sorrounding it. But with all other technolodies in armour I really don't see the advantage of using SLERA, as it's inneffective for most of NS grade weaponry, including anti-tank guided missiles, and it is still rather heavy.
Non-Energetic Reactive Armour and Non-Explosive Reactive Armour: These are NERA and NxRA respectively. NERA, unfortunately, has insubstantial claims against KE, with its rating against CE 400mm RHAe maximum, and even that's a stretch. It's counterpart, NxRA, the ultimate infantry friendly Russian armour scheme has about 150mm vs. KE RHAe and 400mm vs. CE RHAe. The difference between the two seems to be that NxRA is a slightly more volatile reactive armour than NERA, despite the two names. Personally, I wouldn't suggest it for use on an armour vehicle, especially NxRA which I see a lot, since there's still a slight reaction, which will disrupt covering layers of armour unfortunately.
Modular Expandable Armour System: MEXAS is used widely by the Germans and a published paper gives very good ratings for the armour. Unfortunately, attempts to establish credibility of high ratings versus KE failed and it seems that the protection versus KE is rather insubstantial. In terms of effectivity versus CE it seems completely the opposite. The paper claims that at 15 degrees MEXAS is just as effective versus CE as ERA. In fact, it claims that at 7mm of actual thickness it has a value of 250mm, or 1:36. The system seems to work similar as to NxRA but with better results, including a bulging chemical reaction which seems to break up the molten jet coming from a heat warhead. A much safer, and much more conventional claim, however, remains at around 1:20, and just like NxRA, MEXAS absolutely cannot be put underneath other layers of armour because it will disrupt and crack the above layers. But, on a main battle tank, what's the use of having a layer of MEXAS first?
Enhanced Appliqué Armor Kit: EAAK is a French design used on several newer APCs and is wholy an appliqué armour, meaning it can be added by means of putting slabs on it on rails if your tank includes them to handle ERA add-ons, which most do if the ERA is not already included on the tank. When it comes to protection versus CE, which is all it really protects against, the ratio is 1:10 at 45 degrees. What advantages does this hold over MEXAS? Well, for one, it's modular, meaning it's cheaper. Second, it can be applied and taken off at will, and if damaged can be re-applied. In other words it's logistics friendly. Third, it's most likely lighter as well.
Captive Explosive Reactive Armour: CERA was invented by Mekugi and first released to the IADF for investigation. CERA has proved to be a more successful version of SLERA. It works through hexagonal bricks covered with a film of charged metal. Within the hexagon is an explosive propelled by a piston, and so when the round hits the piston sets off the charge and pushed it through the hexagon at ungodly velocities. The latest version, third generation CERA, offers a redesigned rim, increasing gas pressure, and ironically, also increasing safety. It offers 25mm versus KE and 700mm to 1400mm [theoritical] vs. CE.
http://img.photobucket.com/albums/v203/jay3135/Hardware/ceraa.png
http://img.photobucket.com/albums/v203/jay3135/Hardware/cerab.png
So, there you have it. Technically you could include reactive armour, insane levels of ceramic armour and modular armour, but please don't. Realistically, a tank with weight levels underneath 110 tons should have .7 meters or less of actual thickness of the armour. The Abrams, at 68.7 tons, has 384mm of actual thickness in the armour according to the RHAe ratios, while the LeClerc has 400mm. Although armour is not all when it comes to weight, as opposed to the design of certain components and relatively volume in the tank, it is a big part and so designers should be extremely careful when designing the armour on their tanks.
In terms of how much should be slapped on the side and rear., well, the best I can offer you is the following. The glacis armour should have a real thickness roughly 60 to 70% of that of the turret armour. The side armour should have roughly 50% the turret armour while the rear armour should, at most, have 30% of the turret armour. The lower frontal armour should have around 65% of the turret armour ratings.
The Main Gun
The principle armament of the main battle tank will always remain the main gun as long as main battle tanks remain main battle tanks. In the real world there are four main bore sizes including, 105mm and 120mm [the United States], 122mm [some Europeans] and 125mm [Warsaw Pact]. Speaking through generalities, the bigger the bore the longer the range and the more penetration achieved, and in the same way, the longer the gun the same remains true. Unfortunately, this isn't always true. There's a certain threshold limit where the mass of the round is maximized when put into context with the velocity. Warsaw Pact and even modern Russian sabot rounds are known for their innacuracy and their lack of power when lined up against the American 'silver bullet'. This can be attributed to the fact that although the American round is lighter it has a greater velocity, so it achieves more force. Although I can't tell you the exact measurement of mass of the Russian round let's take 7.6kg at 1361m/s against 9kg at 1020m/s^2. So, using a basic force equation [F=ma] you get 10342N[ewtons] and 9180, respectively. Although this doesn't mean that the heavier the worse, a tank designer should really take into consideration the mass of the round and the velocity it achieves and compare this against other permutations. Although it is a bit of work, and to some rather pointless, the round really does offer an advantage in the battlefield.
When it comes to conventional guns there are two principal versions, the smooth bore and the rifled bore. The rifled bore gun, equipped on the Challenger II, increases the lethal range of the round, and it remains the same even on small arms. A rifled bore barrel on a rifle will have a higher lethal range than a smoothbore; an example of a smoothbore small arm is a common shotgun. Rifled bore guns also have the ability of firing HESH rounds, which disputedly smooth bores either can't, or can't so well. Probably the largest issue is that under wartime conditions a rifle bore gun would most likely have to be replaced every 600 or so rounds, which is considerably less than a smooth bore gun. There are also claims that a smoothbore rifle gun has greater accuracy firing APFSDS, as opposed to the rifle bore, and the smooth bore, of course, can fire ATGMs.
Newer advances in gun technology are lead by the electro-thermal chemical gun. Basically, the ETC gun replaces the standard propellant with a surge of electricity that fires a plasma which in turns sets off a chemical propellant. The result is a greater initial, and thus final, velocity for the round. In terms of results Rhinemetal claims a complete 100% increase in the effectivity of the conventional Abrams 120mm round by 2017, although 2020 is a more rounded and more accurate date. Nonetheless, through NationStates perceptions ETC is an early post-modern technology design so you should have no problem using it. However, be wary of the bore in use with the weight of the tank. A tank that weighs somewhere around 70 to 80 tons should have no problem being equipped with a 120mm ETC. To upgun it to a 135mm I really suggest a weight of at least 85 tons, while a 140mm ETC should only be used on a tank of 90 tons and up.
Other upcoming designs include electro-magnetic rifling. There are two types of rifling which you should be aware of, coil and rail. The coil and rail guns work on similar principle although in the coil gun, which is scheduled to be released as a working gun by 2030 [although, again, through etiquette, a common mainstream PMT attribute] and works through a semi or superconductive material woven in the shape of a coil which rifles the gun [as opposed to being a smooth or rifled bore]. In effect, the shell spins in the direction of the electricity running through the coils. There have been grievances that there is a cap in the length of a possible coil gun, which has its merits, and is probably true. The problem is, when the coil rifling gets too long there are threats that the round will actually slow in the rotations meaning the velocity it leaves the barrel at is actually rather slow as compared to a standard gun, or an ETC gun.
Rail guns, on the other hand, use two parallel rails, again with semi or superconducters, although obviously the latter is the better choice and a series of magnets. Using Lorentz' Force and Gauss' Law the round should technically never touch the rails and using superconducters there's no resistance against the electricity, meaning that the only problem with rail guns is the repulsion between the rails which are different charges. Apparently, the U.S. Navy has solved it, detailed in a pdf I read a whilea go which introduces a titanium alloy as the new superconducter in use with the navy and apparently one of the options for the DDX variant with the rail gun. However, there's also a length cap on the rail gun.
Coil guns get less power and are more believable when use on a MBT, and furthermore offer less questions on maintenance and the such although the rifling should probably be replaced after every one hundred or so rounds. It takes a 600 volt battery to power a 120mm ETC gun, so logically it should take around 900 volts to power both an ETC gun and a coil gun, and with increased bore perhaps up to 1000 volts, which is over three times the amount of electricity supplied to European households. But, unlike some more conventional thinkers, I really don't think there are major obstacles prohibiting the early introduction of coil guns into NationStates armour.
Another technique of increasing both the penetration and the range is to use a magnum round. Now, I really can't specify if the magnum round could work in a pure rail gun, but it should be able to do just fine in electro-magnetic rifling since EM rifling on tanks is a bit of a deviation on what a coil gun truly entails. Regardless, magnum rounds have always been used to achieve high velocities, and coined the term high velocity projectile [HVP] guns. The topic was begun on this very thread on the second page and a series of inquiries enlightened me on the true nature of high velocity projectiles, although a few of the earlier things I knew stay true. The Israeli HVP is a stub gun, meaning it has rather short calibre length for its bore size, much like early German tanks did, but this doesn't necessarilly mean that the gun has to stay a stub. Most of the following information is based on what Strathdonia told me, but in effect, a longer barrel, and wider barrel as well, would increase volume required for the propellant to burn properly. In other words, the more time the round has for the propellant to properly ignite the more powerful the round, understandably. Unfortunately, not all is a bed of roses when it comes to using magnum rounds on a tank gun. Barrel wear is absolutely horrendous, dropping the roundabout rating of one thousand rounds per barrel to a mere six hundred rounds per barrel. If you're using an electro-thermal chemical gun with electromagnetic rifling, the wear on the rifling should increase respectively, meaning you would gain even more logistical issues - replacing the barrel, say, every five hundred rounds, or a 50% drop in logistical effectivity. Now, using the example of Hindustani tanks [not real life India, mind you], they don't expect their Sheridan upgrades to really survive that long, so a HPV gun really isn't an issue to them when it comes to logistics - they'll probaby have to replace the whole tank, period.
When it comes to the range of guns a maximum range will always stay withing five thousand to seven thousand meters, like some claims give. In fact, a Tiger was reported knocking out a T-34 at six thousand meters. These claims are luck; for any gun system the optimum maximum range would be at under three thousand meters, with full penetration at under eight hundred meters. Believe it or not, your round loses a lot of energy the farther it goes.
There are a multitude of type of rounds, but they all classify under two principal genres. That is CE and KE. KE stands for kinetic energy and denotes a round that relies on pure momentum, force, and density for penetration. In other words, the round does not rely on an explosive. CE stans for chemical energy, or something which uses an explosive, since explosives are chemically composed. CEs range from HEAT [High Explosive Anti-Tank] to HE [High Explosive] warheads. For tank to tank warfare, KEs on standard get better penetration figures, while CEs are better for man portable weapons since they're lighter and produce far lower recoil [slower muzzle velocity necessary]. Tanks normally carry both, one for tank to tank warfare, and one for anti-infantry warfare. The ratio is up to you and the type of combat you expect.
General Formulas:
Velocity(at range r) = Vmuzzle / (1 + k*r*D^2 / M)
k = pi / 8 * airdensity *; or just use .305
D = sabot diamter
M = mass of the round
r = range
Vr [velocity at the range the round is hitting]
Vmuzzle
mpV2/d3=C(t/d)n
mp = mass of projectile in kg
d = diameter of projectile in mm
V = velocity of projectile at impact in m/s
t = thickness of armor perforated in mm
C = 'constant' that has a varying value, increases as L:d ratio increases [suggest value is 11]
n = 'constant' that has a varying value, generally between 1 & 2, decreases as L:d ratio increases [suggest value 1.33]
Secondary Armament
There's not much to say about secondary armaments. The nature of secondary armaments has seemed to change throughout the years, and while the Germans during the Second World War seemed to focus on machineguns, modern tanks have included a host of other weapons. In general the tank has a coaxial machinegun which is normally mounted right beside the main gun since it follows exactly where the turret points at. These normally measure 7.62mm [NATO round]. Sometimes there's a top gun, like on the M1A2 Abrams which can double as an anti-aircraft gun against helicopters that range from 7.62mm to 12.7mm [NATO]. Some tanks include mortars and even grenade launchers for light suppression and smoke generation for tactical situations. Some tanks even include self-invented systems like Mekugi's SSDs.
http://img526.imageshack.us/img526/2315/ssd6qj.png
The only thing I can think about right now is the firing mechanism of machine guns. The Germans designed it so that it would be a pulley system which fired the machine gun. Others have developed their own systems - I strongly suggest you consider the German method; I've always heard only positive arguments towards it.
When it comes to adding ATGM and SAM launchers, it's feasible. The question is, is it worth mountaing on an MBT? The price should drive up considerably, and it would be just as worth it to mount it on a seperate, cheaper, lighter vehicle, would it not? Regardless, in the end, the tank is yours and prices should be explained a bit better somewhere below.
Engines
When it comes to engines there are two principal types of engines widely used and considered 'conventional' on NationStates. These include the standard turbine/piston engine used by Real Life armour and the newer, less understood, quasiturbine engine. The latter, although truly a future technology [on NS, PMT], is considered a conceivable attribute on a tank and is largely permitted by most NSers. There are a few things to know about each one however, first starting with the conventional engine.
When it comes to the conventional engine the most important aspect is the type of fuel in use. There are three main variants of fuel: Gasoline, Diesel, and Biodiesel. Gasoline was used and is still used on Abrams tanks, although the Army and the Marines are planning to replace all gasoline engines with diesel engines after an entire tank division had to stop and wait for fuel in Operation Desert Storm, allowing an entire concentration of Iraqi soldiers to escape the encirclement during the opening days of the operation. It is to say, gasoline is a relatively bad way to go. Gasoline renders less torque, which is extremely important on a tank, and expends faster. Diesel achieves greater torque, expends slower, but suffers from an increased cost because of the refinement process. Biodiesel expands on the advantages of diesel but is also relatively more expensive, although it is a cleaner fuel. When it comes to conventional engines diesel is the most widely used, with biodiesel coming a close second.
There are few problems with the quasiturbine engine apart from the fact that it has never been tested before on an actual vehicle, heavy or light. The biggest problem that can be seen today is the fact that the engine, now wrought out of ironcast, has a tendency to expand while in use because of the heat. Ergo, it would also have poor ratings against fatigue, creep and resistance. Nevertheless, with modern superalloys, especially those used on aircraft engines and even alloys used in bridging, the problem should be slightly alleviated. Indeed, the best alloy to look for is the one that is accustomed to expansion, and therefore has more resistance to it. When all is taken into mind a quasiturbine really is not a bad choice. In terms of fuel you have the same line up; make a decision for yourself.
Sensors, Defenses and Cost Effectiveness
Now, here is where the tricky part is. In terms of sensors all keep it relatively the same; surface search radar, lidar and ladar, with good ol' fashion infra-red seekers and rangefinders. So, it's not really the sensor suits were tanks start to deviate from the original purpose of the tank, it's the defense mechanisms. For example, let's take shortstop. Most tanks on NS use shortstop. For what? The purpose of shortstop is to set off the fuse of incoming artillery shells before they hit their intended height, and thus rendering them harmless. Unfortunately, shortstop is an expensive system, but it covers a wide area. In all reality shortstop was meant to be used on inexpensive reconnaissance vehicles, like the Humvee, not on tanks. In fact, putting a shortstop electronics suit on every tank capitalizes on how not cost effective that tank is - and in fact, shortstop should increase the price of each tank by a good two million USD.
I won't get into every sensor and defense suit there is, but I think you get the picture. In other words, when you're designing your tank take each system, research it, and evaluate it. The task at hand is to create a cost effective tank - not a vehicle that has so much on it that if it gets knocked out you go bankrupt. You should always look for better ways of employing something. Could you not employ shortstop on a smaller, cheaper, vehicle that can travel with brigades of armour? Even squad level cars? Would not that be cheaper than to employ it on each individual tank? It's that level of thinking which will achieve you a better tank.
In short, what makes a tank good is how much it gets per shot; is the tank worth building? For example, you can take a 27 million dollar tank, which [i]does exist on NS, and compare it to the Abrams, which costs maximum 6 million. In essense, to get its cost effective worth it would take the first tank five kills. Although the Abrams is not state of the art when compared to other tanks on NationStates, a round in the rear at the hands of the conventional 120mm gun would most likely penetrate any tank on NationStates to date. The most likely case is that five Abrams could very well take on that 27 million tank, despite its shortstop, advance armour composite and bigger gun. So, the nation that fields the first tank would go bankrupt, while the nation that fielded the cheaper tank would get off at a more cost effective war with cheaper technology. So, when you're putting in your super advance surface to air missile, think to yourself; do I really need this?
Anti-Tank Systems
As tanks get more expensive anti-tank systems also get more expensive. By all means and purposes the stereotypical anti-tank vehicle, which is turretless, is outdated and obsolete. Nonetheless, there are still types of warheads that will render pretty well against armour including larger HEAT, tandem warheads, LOSATs and shoulder fired fire and forget anti-tank missiles that work similar to the LOSAT [the Javeline].
HEAT has met it's match when it comes to armour, but against certain armours like ERA and chobham the wider the HEAT projectile the better effect it has. Naturally, there's a cap, but HEAT has not been totally phased out and it will be a while before it is. HEAT is still a viable option, especially for a small nation that can't afford any of the more expensive ordnance.
In terms of missiles LOSATs mounted on cheap and light reconnaissance vehicles have actually proved quite capable of engaging and defeating modern battle tanks. In fact, LOSATs offer a cost effective method at destroying a sixteen million dollar piece of equipment at the cost of around two million USD. So, main battle tanks still do not rule the battlefield, and most likely never will. I won't get much into anti-tank weapons here because they belong in another discussion or thread, but MBTs are not an end all, be all weapon. Combined arms young grasshopper!
Conclusions
When putting the tank together you should look less to modern application and more towards your application. In effect, model the tank to serve your military best, and to do this you should analyze your own battles and your own strategy. In fact, there is no 'perfect balance'. To all which meets their needs, as Marx one said. Although I am no Communist within the context of tanks, and without including the context of the statement, it makes sense. Your focus could be firepower, your focus could be velocity; it all depends on how you fight in your own army. For example, the Soviet Union focused on cheap but effective tanks, and in the end they fielded up to tens of thousands of their tanks, despite quite obvious disadvantages, although when the T-62 came out it did sent some NATO experts jumping around. Regardless, I reiterate, the tank should be crafted around the needs of your nation; not the other guy's nation. You know best what you need.
This guide is subject to expand and change. However, good luck with future tank designs!