Some notes on B-tech Weapons capabilitys (and Armor protection)

[Nebfer]

With a few recent threads on B-tech weapons I thought it might be a good idea for me to put up my 2 cents on this subject.
Now I do not clam to be 100% correct on this, but I have done more than one debate on B-tech, and much of the info I have used on this comes from the rules and fluff. Now Battletech is a very hard universe to get any idea on what it can do, and at times contradictory. Nor is it a universe that showcases it's technology very much, focusing more on people than technology. As such it dose not have teloporters, nanotech, advanced AIs and the like.

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Turn length
1: A regular B-tech turn is 10 seconds long, but the firing phase only takes place during a fraction of that time, after all the range calculation is based on where the units end up and not where they start from. This also applys to Capital scale's minute long turns. 
2: Rule sets such as the old dueling rules reduced each turn to 2.5 seconds, and allowed a weapon to be fired every turn if the player wanted to (with a resulting monumental heat spike), thus further indicating that B-tech weapons fire takes place in less than a full 10 second turn.

Armor composition
1: B-tech armor is a composite  comprising two main layers, the first is a Super hard steel alloy, the second is Cubic boron nitride (CBN) reinforced by diamond mono-filament, a third layer made from honey combed titanium acts as a structural support.
2: Ferro-Fibrous reinforces the steel layer with diamond mono-filament (a real trick)
3: due to the known armor mass on B-tech units and the large surface area mechs have, the armor would be at best about an inch thick, more likely less.

Energy Resistance capability's
1: The Fluff commonly mentions that the armor is routinely melted by a laser or particle cannon hit, with a few references to vaporization.
2: Assuming the armor is a 50 / 50 mix of Steel and CBN with a single point (62.5kg) of armor having roughly 30kg of each, and assuming the armor is melted.
3: The Steel layer would take about 28 megajoules to melt, the CBN layer would take about 170 megajoules for a combined total of just under 200 megajoules to melt one point of armor.
4: If one wanted to vaporize a single point of armor then the energy required would be roughly 450 megajoules or so. Though not all of the armor has to be vaporized or even melted (i.e. falling off) which would reduced the energy required.
5: As such a small laser would range from 100 megajoules to 1.5 gigajoules in power or more, depending on the values you use, but a full melt number would result in a small laser having 600 megajoules. And a Clan Heavy Large Laser would range from 530 Megajoules to 7.2 gigajoules with the full melting numbers being 3.2 gigajoules.

Kinetic Energy Resistance
1: Autocannons are not typically used to get an idea of Ke Resistance due to largely unknown variables (how much mass is the propellant charge, how many rounds in a single shot, etc...), As such Gauss Rifles are preferred here.
2: Gauss Rifles are stated to fire hypersonic rounds (their are some quotes suggesting lower but I have found a lot more quotes supporting the higher speeds, never mind the rules...). Hypersonic is any velocity faster than Mach 5 (to about Mach 10ish) or 1,710m/s (~5,600fps). Though their not likely to be right at the hypersonic line but quite a bit faster than that. Particularly when using the ranges provided with capital scale a Gauss Rifle has a minimum MV of 6km/s (and a range of 360km -in space), though I'm not to fond of using these values, their a bit wacky, though they at the lest suggest that B-tech weapons have a very high MV. 
3: Let's assume than a Gauss rifle has a MV of 2,200m/s (~mach 6.5, comfortably in the hypersonic range), as such a regular Gauss Rifle would have a Ke of 300 megajoules or roughly 20 megajoules per damage point. When scaled a heavy Gauss Rifle slug at 250kg (vs 125kg of the "regular Gauss") would have a MV of 2,000m/s and a Ke of some 500 megajoules.
4: 300 Megajoules (Mj) is roughly equivalent to a 16 inch battleships gun (like the ones on the North Carolina and South Dakota class's -which produced ~300 Mj at the muzzle) and 500 Mj is considerably more than the 18.1 inch guns on the Yamato (~440Mj).
5: Considering that B-tech armor is less than an inch thick and is perfectly capable of stopping multiple Gauss Impacts B-tech armor is quite impressive in this area (considering that current day tanks would be reduced to scrap when hit by a 16 inch naval shell). As such I find it unlikely that a real life Ke tank round is going to be all that effective on mech armor (also note than most real life tank rounds produce less than 9Mj of Ke).
6: While Autocannons are not typically used in such calculations they do fire hypervelocity shells (IIRC velocity's above 2km/s), though for the most part references to these speeds are uncommon, with the more generic term "high speed streams" being more often used. Also like wise capital scale ranges require very high velocity's to acheave.
7: As such even a weak weapon such a the AC-2 is quite powerful, being some five times more powerful (if not more) than most current tank guns.

Weakness
1: B-tech Armor seems to be weaker to burst fire weapons like Machineguns, hence why autocannons where created, as single shot weapons had to resort to firing really big rounds in order to start damaging the armor
2: B-tech Armor also is weaker to high mass and low velocity impacts than to high velocity and low mass impacts, such as melee attacks and falling damage.

Range
1: Total Warfare Mentions that the "relitvly low" ranges are due to game play purposes, and not truly indicative of the universe (even then they still like to use them in fluff...).
2: Tactical ops introduces the Line of sight rules which allows many weapons to have ranges out to the units line of sight (which on a flat plain would be roughly out to the horizon or some 15km distant)
3: Tactical ops also introduces "Rifle" cannons, primitive weapons introduced and developed in the centuries before the autocannon was introduced in 2250, and is smiler to weapons we would use today (the "light rifle cannon" even has a smiler weight to current tank guns). One can use these weapons in-game range to get an idea of how much the ranges have been reduced for game play (basically, by roughly a factor of six to 14, depending on which B-tech weapon you use and the what real life range you use (i.e. three to five kilometers is typical for real life tanks)).
4: Strategic ops allows mechs and other units to be used in space, though they can only fire at units in their own hex, giving them a range of 9 to 18km (depending on the POV of where the mech is in the hex).

Infantry Weapons.
Well B-tech weapons are powerful and the armor equally as tough but how dose this apply to infantry weapons?
Their is some evidence for Infantry weapons being quite powerful in their own right. For example the fluff describes the Zeus Heavy Rifle as a 12.7mm weapon firing a 45 gram slug at hypersonic velocity's, thats at lest 65 kilojoules (more than three times the power of a 50 cal BMG round). Other Examples include a Laser pistol that has a yield of 100 kilojoules per shot (or 20g of TNT), Laser Rifles exploding heads, Tsunami Gauss Rifles with 1.5Mj of Ke, the well known Magshot delivering over 500 kilojoules of Ke and so on. Oh and their is some mention of "Nuclear" hand grenades...

And for thoughs who wounder what calibers B-tech autocannons are, well here's a list of Calibers that I have found.

In short from the fluff your typical Autocannon seems to be...
AC-2s = 30mm, with notable exceptions
AC-5s = 40 to 80mm guns, with notable exceptions
AC-10s = 80 to 100mm guns, with notable exceptions
AC-20s = 100 to 120mm guns, with notable exceptions

And Here's the "full" list of what I have been able to find, though it's not complete and it's some times contradictory.

SarLon AC-2 =30mm (TRO 3026) -Warrior VTOL
Mydron Model D AC-2 =30mm (Threads of ambition) -Jagermech
Whirlwind-L AC-2 =30mm (Threads of ambition) -Blackjack
Mydron Model D-rf Ultra AC-2 =20mm (Imminent Crisis) -Jagermech III

Armstrong J-11 AC-5 =80mm (Decision at thunder rift) Shadow Hawk
GM Whirlwind AC-5 =120mm (Decision at thunder rift) Marauder (in killing fields it's a 50mm...)
Armstrong Autocannon/5 AC-5 = 50mm (Double blind) Clint
General Motors Nova-5 Ultra AC-5 =50mm (Binding Force) Cataphract (note in Illusions of victory the same type of mech is said to have a 40mm UAC-5)
Imperator Ultra AC-5 = 80mm (Storms of fate) Vulcan 5S & Daikyu (same guns)
RAC-5 (type unknown -either a Mydron RC or Tornado) = 80mm (end game) Jagermech 7F
Pontiac "Light" AC-5 =40mm (Illusions of victory) Striker (mech)
Mydron Snakekiller LAC-5 =60mm (Battlecorps fluff on the Shadow hawk)
Mydron Model RC RAC-5 =50mm (several DA books) -Legionnaire (Note a number of other DA era RACs-5s are also listed as being 50mm)
Armstrong AC-5 = 105mm (TRo3075)  -Merkava tank (NO RELATION TO THE REAL LIFE TANK OF THIS NAME!)
Unknown AC-5 = 110mm  (Birth of a King scenario) -Mackie 5S

Luxor D-Series AC-10 =80mm (Ghost of Winter) Centurion 9A (though I have seen other references to 30mm or 70mm...)
Federated Autocannon/10  AC-10 =100mm  (Double blind) Enforcer
Merdron Excell UAC-10 =80mm (Patriots and tyrants) Enforcer III, Dragon fire (both have the same type of gun) & Cataphract (Illusions of victory)
Imperator Code Red LBX-10 =100mm (Flashpoint) Challenger X MBTs (the same gun on the Emperor is listed as a 80mm in Illusions of victory)
KaliYama AC-10 =80mm (Illusions of victory) Orion

Armstrong Autocannon/20 AC-20 =120mm (binding force) Von Luckner
Pontiac 100 AC-20 = 100mm (Heir to the dragon) Victor
Deathgiver AC-20 = 100mm (Heir to the dragon) Atlas
Chemjet AC-20 =185mm (TRO 3026) Demolisher
Crusher SH AC-20 =150mm (TRO 3026) Hetzer
Defiance Thunder Ultra AC-20 =120mm (Patriots and Tyrants) Blitzkrieg
Defiance Disintegrator LBX-20 =120mm (Patriots and Tyrants) Barghest

Clan tanks TRO 3060
LBX-5 AC type COVR-X: 40mm (Zorya)
LBX-10 AC Type KOV: 75mm or 150mm (same gun on Mars & Ishtar but different caliber...)
Ultra AC-2 type 25: 50mm (Mithras)
Ultra AC-5 type 31: 40mm (Heuy)
Ultra AC-10 type 9: 75mm (Istar & Ku)

Invading Clans Sorcebook
Caldron born Alt A: UAC-20 = 203m
Caldron born Alt C: UAC-2 = 25mm
Caldron born Primary: LBX-5 = 75mm

Unknown Ultra AC-2 =30mm (Patriots and tyrants) Daishi
Type-20 Ultra AC-20: = 200mm (Battlecorps) Fire Scorpion 3

[HAARP]

Interesting read and I am impressed by the volume of knowledge compressed into this thread.

But what's the point? It is obvious that Battletech is written by so many authors, split into so many games, minigames, novels, source books, adaptations. Loopholes and different systems can't be avoided.
And that some values just plainly don't make sense (armor absorbing thousands of megajoules of energy, weapon ranges, etc.) for the sake of gameplay has always been known. Of course, seeing real numbers here is interesting nonetheless. +karma.

[(TLL)KitLightning]

Nice reference list

I'll take a pair of Chemjet' for my Demolisher

[(TLL)Sky_walker]

Most impressive!
Thank You granted!

[Nebfer]

Interesting read and I am impressed by the volume of knowledge compressed into this thread.

But what's the point? It is obvious that Battletech is written by so many authors, split into so many games, minigames, novels, source books, adaptations. Loopholes and different systems can't be avoided.
And that some values just plainly don't make sense (armor absorbing thousands of megajoules of energy, weapon ranges, etc.) for the sake of gameplay has always been known. Of course, seeing real numbers here is interesting nonetheless. +karma.

The point is well to show just how strong B-tech weapons and armor is.

Well one thing to note is your never gonna get a good workable system to explain how B-tech armor works, theirs just a lot of oddity's to make one system work very well. The numbers required to melt armor is high but that's what is required, though one could argue that only part of the armor is melted with the rest being removed along with it or rendered useless, that could drop the numbers a fair amount to about half or so. And then theirs Capital scale damage, and it's armor...


Though in many areas Battletech is little different than say Starwars, Warhammer 40k or even Startrek, to name a few. All of them have strong weapons, with the ones I named well their capital weapons are way stronger than B-techs (gigaton levels in some of them).

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Edit:
Well here's some fluff on MGs being 20mm or larger, as it comes up some times.

    And then Evan stumbled backward as the Ranger’s machine guns opened up, slamming twenty-millimeter
    caseless into the ConstructionMech’s bulky frame.

    There, a cadet-crewed Schmitt probed forward, found a Triarii infantry position exposed
    and hammered twenty-mil rounds into their position.

The Di Schmitt has two ballistic weapons a pair of Mydron Tornado RAC-5s and a pair of Scattergun Machineguns. The RAC-5s are described earlier in the book as being 50mm, leaving these 20mm weapons as the Machineguns.

    Some I can see. A whole lot I can’t. Gun trucks with machine
    guns and grenade launchers... ...His gun truck bounced over brush and rocks as it shot forward, three more swinging out in rough
    echelon as they zigged and zagged behind him. Gunners hung on to their 20mm Gatling guns attached to
    the roll bars on the enemy side of the trucks.

    Armament:
    3 Holly SRM 6
    4 Holly SRM 4
    2 22mm Gatling Guns

The TRO entry lists the 22mm Gatling Guns as Machineguns.

    The 20mm Gatling gun is a time-proven weapon, giving the Scorpion good defensive firepower with plenty of punch.  Though some users of the tank have tried 30 mm machine guns, the Gatling gun's high rate of fire makes larger shells unnecessary.

In short B-tech MGs are in the same caliber range as Autocannon 2s and often rotary, though MGs are optimized for anti-Infantry duty not anti-Armory, though how the MG manages to deal smiler damage as a AC-2 with 1/4th the shot mass, is one of the oddity's in the system, though the fluff often mentions that MGs are not all that effective on mechs any way, so perhaps the game has buffed the MGs ability's...

[~SJ~ Atlessa]

In short B-tech MGs are in the same caliber range as Autocannon 2s and often rotary, though MGs are optimized for anti-armor duty not anti-infantry, though how the MG manages to deal smiler damage as a AC-2 with 1/4th the shot mass, is one of the oddity's in the system, though the fluff often mentions that MGs are not all that effective on mechs any way, so perhaps the game has buffed the MGs ability's...

Simple: you don't have one MG, you have an array of three to four of them, leading to effectively more lead flung towards the enemy

[Nebfer]

In short B-tech MGs are in the same caliber range as Autocannon 2s and often rotary, though MGs are optimized for anti-armor duty not anti-infantry, though how the MG manages to deal smiler damage as a AC-2 with 1/4th the shot mass, is one of the oddity's in the system, though the fluff often mentions that MGs are not all that effective on mechs any way, so perhaps the game has buffed the MGs ability's...

Simple: you don't have one MG, you have an array of three to four of them, leading to effectively more lead flung towards the enemy

hehe

However that's not the problem, an AC-2 dose 2 damage and uses 22kg worth of ammo, a MG dose 2 damage and uses only 5kg of ammo. A MG Array would do 4x2 damage and use 20kg of ammo.

[(TLL) Heretic]

*Applause*

Put it this way, any time I hear the usual asinine "21st Century is better than 30the Century because.X, Y & bloody Z" arguments I now have a post to refer them too.

Thanks Nebfer.

PS. IIRC that Shadow Hawks AC5 is 90mm (Decision at Thunder Rift), and in the same book the twin Machine Guns on the Hover tank (GEV?) that Grayson uses to dispatch his first 'mech is listed as 20mm...The Marauders AC10 is described as 120mm (IIRC, in the 1st 3 GDL books it gets a couple of mentions).  I'm re-reading the GDL books at the moment (on a nostalgic 3025 kick and those 3 are amongst my favourites), I finished Mercs Star last week, finishing Price of Glory right now, and might just stop there...before things become heartbreaking  .....I'll probably move on the Warrior series next and avoid the pain.

[Nebfer]

No I'm pretty sure it was 80mm for the shadow hawk, though I do not recall a caliber being stated for the "GEV" tanks Machinegun, other than it fired at 1,500 RPM, though a battlemech could scan a man to find out what kind of warhead his missile launcher has, Grayson tells the Locust to do that to see that he as not bluffing, he was not and the locust pilot has a fear of flames...

And a Marauder has a AC-5, which I listed.

I just noticed some notes I had, I forgot to add a few, and they do come from Price of Glory, the Riflemen's AC-5 is 80mm, and the Wolverine's AC-5 is a 60mm, which is odd as it's a GM-Whirlwind, the same gun on the Marauder. Also the Centurion in this book has a 80mm AC-10, in the previous book it's listed as a 30mm...   luckily in Ghost of Winter it's listed as 80mm.

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Some more thoughts on B-tech armors kinetic resistance.
As I said earlier, at best the armor is an inch thick. A 13m tall Atlas (I'm not 100% on it's height but it's between 12 and 14m tall) only has 19.5 tons of armor (the max any mech can carry out side of heavy armor), and a mechs surface area is easily between 200 and 400 square meters.

When you get to the point when like 10-25mm or so of armor can stop the Kinetic Energy equivalent of a 16 inch battleships round and do it more than once (Some B-tech tanks can take up to seven Gauss Rounds to their front hulls and not go internal), and that a 16 inch naval round can already penetrate 36 inchs of steel (the same as current tank weapons). It gets kinda hard to justify a ~8 megajoule impacter (i.e. 120mm M829A3) going clean through a mechs armor, even though it technically may be a better penetrator. Particularly when the same battleships shell hitting a current day tank would reduce it to scrap.

In real life tanks are most often knocked out by a shell making a small hole in the armor and hitting something vital on the inside, a critical hit, so to speak. In battletech a Mech or a tank are more often knocked out after the armor has been "removed" and the internal hull has be wrecked. In other words B-tech resorts to reducing the unit to scrap.

[~SJ~ Atlessa]

In short B-tech MGs are in the same caliber range as Autocannon 2s and often rotary, though MGs are optimized for anti-armor duty not anti-infantry, though how the MG manages to deal smiler damage as a AC-2 with 1/4th the shot mass, is one of the oddity's in the system, though the fluff often mentions that MGs are not all that effective on mechs any way, so perhaps the game has buffed the MGs ability's...

Simple: you don't have one MG, you have an array of three to four of them, leading to effectively more lead flung towards the enemy

hehe

However that's not the problem, an AC-2 dose 2 damage and uses 22kg worth of ammo, a MG dose 2 damage and uses only 5kg of ammo. A MG Array would do 4x2 damage and use 20kg of ammo.

Maybe the fact that ACs fire explosive shells can explain the difference?

As in: BT armor is more resistant to explosive shells than to simple AP slugs (up to a certain caliber at least)

[Nebfer]

Well here's a few notes on artillery, and just how big are they.

At 30 metric tons the Long tom is not that far off from historical guns of it's size.
Sense a Long tom uses 200 kilograms per shot a Long tom is easily in the 9 to 10 inch range (228 to 254mm). As 203mm guns fired ~105kg (land based it's 90kgs naval it's ~120kgs) shells, so 203mm guns are a bit to light.

The M1 240mm (9.45in) Super Heavy Howitzer of WW2 (and Korea) fame, was a massive 29.35 metric tons and fired 160kg shells.
The German 24cm H39 siege howitzer was 27 metric tons and fired a smiler shell. -Just add ~40kg for propellant and theirs your 200kg shot.

For "Snipers" it's 100kg shot puts it the range of 170mm guns like the 17cm K18, M107 SPH and the 180mm S-23. The weight is not to far off as well at 20 tons (the K18 is 17 tons (interestingly it's travel weight was 23 metric tons), the M107 is a SPH so no real numbers on the gun weight, but the soviet S-23 was 21 metric tons.)

This leaves the Thumper, at 50kgs per round and 15 metric tons in weight. It's shell weight is close to 130mm but guns of that size are half the weight.

Arrow 4s are well short range tactical missiles. Though I have not found any real good analogs in a smiler weight range.

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Missiles.
Missiles are a bit hard to get a Idea of how powerful they are, so I can only give some basics, in the second book of the warriors of Kerensky series, Victor and crew are in a wolf dragoons meeting hall, when they find a 3kg block of explosives under the table, well they describe the explosives as capable of demolishing the entire level of the building they where in. On page eight of the old house Laio book it mentions nuclear hand grenades (this is also mentioned in Jihad Terra book), though no info if these weapons are still around however. If B-tech can make "hand grenade" sized "nukes", I wonder what they could do with regular explosives (multiple "nuke grenades" where described as destroying three city blocks, in the Laio book).
Also IIRC their are a few times when Elemental's get hit by some LRMs or SRMs and they go flying, dead or not...

An LRM is a 8.33kg "semi-guided" missile, likely optical guided (if LRMs are not guided then why don't they have a -1 to hit like MRMs and Rockets, which attribute the -1 due to the lack of guidance systems), though its a limited guidance package at best in any case (after all LRMs are cheap very cheap, at only 250 C-bills per round (less than 1,300 USD)). At 8.33kg a LRM is 1.6kg heavier than a 105mm RPG-29 round (6.7kg) or 1.2kg heavier than the MILAN 3 missile (7.1kg). SRMs are 10kg, and like LRMs are "semi-guided", at 10kgs their 1.8kgs less than a Javelin Anti-tank missile (which is 11.8kg, thats the missile, the other gear adds more weight).

MRMs are 4.166kg in weight which are comparable in weight to LAWs and other "RPGs", and are effectively dumb fire rounds, due to a lack of built in guidance systems. And Clan ATMs are 16.66kg (on the lighter end of the heavier "man" portable ATGMs like the TOW).

In essence a SRM 6 is firing a half a dozen Javelin analogs in a volley, a LRM 20 is firing 20 RPG-29 or MILAN analogs and MRM 40s are firing 40 LAWs at a time.

[~SJ~KorbinWimmer]

In essence a SRM 6 is firing a half a dozen Javelin analogs in a volley, a LRM 20 is firing 20 RPG-29 or MILAN analogs and MRM 40s are firing 40 LAWs at a time.

Awesome job, great read.

[Nebfer]

Stealth

Battletech as a wide array of Stealth Technology's available.

Battlemech Stealth Armor
Invented in 3063 by the Capellan Confederation in an attempt to mimic the old Starleage Null sig armor. It is in it self a adaptation of Ferro-fibrous Armor, that is also a complex array of heat baffles, radar and Electromagnetic absorbent materials, though to be trully effective it requires an Active ECM component in the Guardian ECM pod (which is a broad spectrum device, covering a wide range of EM types). In the early 3070s Vehicles & Aircraft started to get their own counter part to mech Stealth armor (in the current RPG it works on IR and EM based sensors, and the GECM works on the EM side of things).

On a side note, Aerospace fighters with Stealth Armor do not get any stealth modifiers if the unit is expending thrust, This is due to the fact that their is no real stealth in space as it's almost impossible to hide the Exhaust from a Fusion torch (and Battletech drives are very very powerful). However in space if the unit is costing you do get the benefits of Stealth armor, even if you are firing large amounts of energy weapons (and all the heat they produce...) which provides an interesting thought but I'll come back to that later. Atmospheric operations get the full benefits of Stealth armor though.

Null Sig Armor (Starleage created in 2630 and went extent in 2790)
This is the Starleage counter part to the "modern" Capellan Stealth armor, it's a bit more advanced as it dose not require a GECM pod to be effective. This armor works with the Chameleon Light Polarization Shield (CLPS).

Chameleon Light Polarization Shield (Starleage created in 2630 and went extent in 2790)
This Armor is a Optical based Stealth System, in fact current B-tech mimetic armors are a bit more advanced than this device. The CLPS is a Series of Computers and cameras tied into a special pigment that allow it to shift colors based on the terrain the mech is found in. While it dose not make the mech truly invisible it dose reduce it's outlines at range.

Void Sig Armor (introduced in the 3070s by the Word of Blake)
This is a "upgrade" of sorts to the older Null Sig and Chameleon LPS system, It's basically a full up mech scale Mimetic Armor making the mech almost invisible to optical systems, and with the "required" ECM gear almost invisible to IR and Electromagnetic based sensors as well. However the faster the unit goes the less effective the mimetic armor is. And at speeds above 54kph it hardly works at all.

Battle Armor Stealth Armors
Stealth Armor
Comes in a few configurations of different strength and ability's (as well as weight and cost). Like Mech Armor It works on IR and EM based suppression techniques. However unlike Mech Scale Stealth armor, Battle Armor stealth also includes some optical based stealthing.

BA Mimetic Armor, this actually comes in two flavors on is Armor based and the other is a add on package not tied to the armor, both work the same, by using a series of cameras, computers and special pigments to change the color of the units "skin" thus blending in with the back ground, but like with it's larger scale counter part(s) the faster the unit goes the less effect it has.  The add on package is not quite as good as the Full up Mimetic armor but it dose work with regular BA Stealth Armor (though the full up Mimetic dose have some EM and IR stealth ability's -but not on the same level as the other kinds). 

Also Regular Infantry can get IR, EM and Optical based Stealth suits (and in any combination), though these are more often seen in spec ops forces than line infantry.

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Now for that interesting though I mentioned earlier.

B-tech it seems has Decent IR stealthing even on basic units, after all a battlemech standing still at rest has a smiler IR reading as a infantry platoon of some 30 guys, B-tech Stealth armor also seems to ignore the effects of weapons heat, even in space, though with the drive lit up the stealth in space dose not work (considering just how much energy b-tech energy weapons use...)
And the fact that when B-tech dose use IR missile they only work on units that are over heating.

[HAARP]

Very good summary and interesting thoughts.

[~SJ~ Wolf]

A great read. Thanks for sharing this with us.