What works? How are ships and vehicles armed?

[TamsinP]

@Spinward Flow
No. Really, no. We were only pointing out that armour as a percentage of hull leads to the bizarre effect where (using the example of a spherical vessel) 17 cm of armour on a 10 dTon fighter affords the same protection as 360 cm on a 100,000 dTon battleship. That was in response to this comment:

imho ... the REAL problem lies in 10 cm of armor on a small ship being equal to 10 meters of armor on a giant ship for ARMOR FACTOR and thus negating penetration. [some hyperbole, but sadly, not much]. THAT was the simplification that went 1 step too far and broke verisimilitude.

I actually agree with you on the point that it would be nigh on impossible to derive a formula which takes into account both tonnage and configuration to give a consistent thickness for each factor of armour; at best a rough approximation can be attained. At least, that is what I assume you are arguing.

MegaTraveller does make an effort towards accounting for configuration and hull size in determining the mass of armour. MgT2e has armour volume modifiers for configuration and also for craft under 100 dTons (but not for very large ships); it also has a system of Hull Points, modified by hull type (light, standard, reinforced) and you can add Armoured Bulkheads to reduce the effect of critical hits on components they are added to.

As for the argument of armour being only an external shell, versus a mix of internal and external...

Well, that takes us back to 17 cm thickness of armour distributed throughout a spherical 10 dTon fighter being just as protective as 360 cm thickness of armour distributed throughout a spherical 100,000 dTon battleship.

 

[Rupert]

Are later versions of Traveller written for different systems retroactively "binding" on earlier systems?
The fact that many of the same authors worked on both is "nice to know" (for historical reasons), but is not germane to what is written for how LBB5.80 works and why.

Kind of like how later versions of D&D have Feats ... but the first editions of D&D did not.
The first versions of D&D used the THAC0 system ... which was (fortunately) later revised into the DC system.
Yes, the later versions "grew out of the former" ... but you can't just backport everything 1:1 and expect nothing to go wrong when it comes to reconciling everything involved.

This thread wasn't 'CT only', so other rules are relevant to the general discussion. Also, I think when rules aren't clear, looking elsewhere for authorial intent can be useful, or at least interesting.

If the authors meant for armour to be largely internal, we would expect later rules for the same setting by them to reflect that. We don't see that.

LBB5.80, p18:
Meson Guns create high energy mesons and direct them at targets. Mesons have short lives, which can be prolonged to precise durations by accelerating them to relativistic speeds. If the point of decay is manipulated to occur inside the target ship, the result is high energy explosions and radiation damage. Because of the nature of the meson, it can pass through armor and matter without resistance.

That passage is why internal armour should affect a meson gun hit - you get 'explosions' and a 'relatively' small point source of radiation (that configuration is a form of protection supports this). Thus heavy interior armour would serve to restrict the damage to those compartments that the hit decayed in. Hence, if armour is, or includes, massive interior bulkheads, it should give some mitigation of meson gun hits. That it provides none at all while sheer bulk provides some protection from really big hits suggests that the author's saw armour as being a shell.

The 'small compartments, heavy bulkheads' model explains armour being a percentage of volume and scaling with volume not surface area, and is quite an interesting idea, but it's not consistent with other parts of the rules, and I don't think it was the author's intent.

 

[Rupert]

@Spinward Flow
No. Really, no. We were only pointing out that armour as a percentage of hull leads to the bizarre effect where (using the example of a spherical vessel) 17 cm of armour on a 10 dTon fighter affords the same protection as 360 cm on a 100,000 dTon battleship. That was in response to this comment:


I actually agree with you on the point that it would be nigh on impossible to derive a formula which takes into account both tonnage and configuration to give a consistent thickness for each factor of armour; at best a rough approximation can be attained. At least, that is what I assume you are arguing.

MegaTraveller does make an effort towards accounting for configuration and hull size in determining the mass of armour. MgT2e has armour volume modifiers for configuration and also for craft under 100 dTons (but not for very large ships); it also has a system of Hull Points, modified by hull type (light, standard, reinforced) and you can add Armoured Bulkheads to reduce the effect of critical hits on components they are added to.

As for the argument of armour being only an external shell, versus a mix of internal and external...

Well, that takes us back to 17 cm thickness of armour distributed throughout a spherical 10 dTon fighter being just as protective as 360 cm thickness of armour distributed throughout a spherical 100,000 dTon battleship.

TNE and GT use surface area when calculating armour mass, and thus allow for size and configuration, at least in general terms.

 

[Spinward Flow]

The 'small compartments, heavy bulkheads' model explains armour being a percentage of volume and scaling with volume not surface area, and is quite an interesting idea, but it's not consistent with other parts of the rules, and I don't think it was the author's intent.

To be excessively fair to the original authors (and the conditions they were writing in), they were probably thinking more in terms of quick and dirty/simple game mechanics that worked for the construction and combat systems, rather than gaming out all of the knock on effects that would show up in deck plans. We (almost 50 years later) have the benefits of time, tools and tech manuals (not to mention, later developments) to fall back on and try to find all kinds of corollary points to try and divine Original Intent™ (as if we were reading tea leaves). I really don't believe that the original writing behind LBB5.80 goes as "deep" into all the interconnected factors as we've been enjoying talking about in this thread.

CT did a great job of creating an open framework to be built upon and built outwards from, rather than crafting a hermetically sealed "closed" system where the only things that existed had to come from official sources.

At this point, the answer to the question of armor thickness relative to Original Intent™ is almost a moot point, partially because it wasn't truly relevant to how starships got detailed in CT. That makes the answer to the question a kind of "nice to know" bit of Fluff Text™ but it isn't something with controlling game mechanical relevance to how combat works using USP codes for all relevant parameters.

In other words, there are opportunities for excuses in any direction you want to go with this question of "is armor factor the same at disparate tonnages" and when you boil things down to how the combat game mechanics work, the answer is substantially (but not completely/totally) yes. The difference is that smaller hulls are more prone to critical hit failures than large hulls are from the same weapon factors of incoming fire, but other than that, Surface/Radiation/Interior damage table results are pretty much "agnostic" with respect to hull size, because identical armor factors provide the same +DMs on those tables regardless of hull sizes. Make of that fact whatever you want to.

 

[mike wightman]

FF&S does it and if you want a streamlined version then there is GT:ISW.

Step 1 - determine hull surface area (both FF&S and GT:ISW give a simplified way of doing this or you could do it the hard but rewarding way)
Step 2 - allocate armour thickness to achieve desired AV
Step 3 - calculate armour volume and subtract from remaining hull internal volume.

 

[Spinward Flow]

LBB5.80, p28-29:

Armor: Hulls may be armored with strengthened exterior skins and interior bracing. Such armor is not possible on ships with dispersed structure (configuration 7). The armor factor is the type of armor used; if no armor is selected, the armor factor in the USP is zero. The armor table indicates formulae for the computation of armor tonnage and cost, based on the factor selected. For example, the formula at tech level 9 is 4+4a (a is armor factor). On a 100-ton ship with an armor factor of 3, this formula indicates that the ship must allocate 16% (4+4x3), or 16 tons. Cost is MCr.3+.1a per ton; the cost per ton is MCr.6 (.3+.1x3), or MCr9.6 (16 tons times MCr.6) total for the ship. The added value of armor on a ship may not exceed the ship's tech level.
When armor is used, the entire hull is armored. Dispersed structures cannot be armored, and have a hull armor factor of 0. Planetoids (configuration 8) have an automatic hull armor factor of 3; buffered planetoids (configuration 9) have an automatic hull armor factor of 6. Additional armor may be added to planetoids.

Hulls may be armored with strengthened exterior skins and interior bracing.



Strengthened exterior skins AND interior bracing.
So the armor applies to the exterior AND interior of craft ... rather than being an exterior only implementation.



When armor is used, the entire hull is armored.



The ENTIRE hull.
Not just the exterior ... ALL of it ... inside AND out.

 

[atpollard]

LBB5.80, p28: "Such armor is not possible on ships with dispersed structure (configuration 7)."

If every little compartment was armored internally, then THIS would NOT be true.
This IS true of a thick outer shell with minimal internal reinforcing (like the bulkhead that separates ENGINEERING from the rest of the ship in the Standard Hull sizes in LBB2).

 

[atpollard]

When armor is used, the entire hull is armored.



The ENTIRE hull.
Not just the exterior ... ALL of it ... inside AND out.

I am pretty sure that their intent was to prevent people from just armoring the ENGINEERING to protect the drives and not armoring the fuel (or any other scheme to create unequal armor for each component).

This is actually an argument for a uniform thick outer shell. Internal armored spaces would perfectly lend themselves to a different armor level for each component.

 

[Badenov]

When armor is used, the entire hull is armored.

As an amusing counterpoint to this, capital vessels in Mg1 are divided into sections based on the overall tonnage of the ship, and the armor can be allocated on a per–section basis, so you could, if you wanted to, just armor engineering. Why you would do this, I don't know. Max armor in Mg1 is proof against turreted weapons, but bays will still hurt you, if not as much as they would if you'd skipped the armor.

 

[kilemall]

I am pretty sure that their intent was to prevent people from just armoring the ENGINEERING to protect the drives and not armoring the fuel (or any other scheme to create unequal armor for each component).

Real life warships do exactly this, along with tanks and glacis vs side/top armor.

But HG is about having a standard USP in service to a line em up design QA demolition derby in TCS. Nuance is out the door in a blizzard of dice.

 

[Spinward Flow]

LBB5.80, p28: "Such armor is not possible on ships with dispersed structure (configuration 7)."

My interpretation of this point (which is more of a personal preference than explicit RAW, because it is an interpretation of the RAW) is that the Dispersed Structure (configuration: 7) is more of a "naked skeletal going in all directions" type of construction (think ISS) where stuff can just be "bolted on anywhere convenient" and it's all just "hanging out in the open" with plenty of space between bits, modules and sections. Totally unstreamlined with no "uniform enclosure" around stuff, so everything is exposed to space (rather than being swaddled in fuel, like is often done in other configurations). Makes it almost impossible to armor everything to the same standard (too many joints and crevasses between pieces) so just say that Configuration: 7 can be Armor: 0 only and call it a day.

Those features of "naked skeletal going in all directions" is then what justifies the -50% configuration modifier to hull cost, why Configuration: 7 can launch and recover ALL sub-craft in a single combat round (without needing launch tube support infrastructure) and why Configuration: 7 has the best passive defense against meson guns ... because everything is "spread out" with gaps in between, so it's really easy for a meson gun decay point to fall "outside the hull" while still being within the overall dimensional (hit box) bounds of the extremities of the construction (but there's still LOTS of empty space(s) within those boundary limits, so plenty of opportunities to miss the necessary pinpoint accuracy to hit inside something).

Examples of Configuration: 7 designs would be the aforementioned ISS (real world) ... as well as the Discovery (2001, 2010, Arthur C Clarke) and the ISV Venture Star (Avatar, Avatar 2, James Cameron).

 

[Rupert]

Real life warships do exactly this, along with tanks and glacis vs side/top armor.

Historically warships have had a huge range of armour schemes. Sometimes effectively everything in the hull was armoured. Most times do this with enough armour to matter was too heavy, so various partial schemes were used. Just what those schemes protected and how depended on what threat they were protected against. In the late 19th century gun and armour technology advanced so fast that all this was changing year to year, and ships were often effectively obsolete before they even entered service.

 

[Enoki]

With High Guard, one of the things I came up with was the "All or nothing" battleship. This was a design that had the most powerful spinal mount weapon you could get, enough power to run it and let the ship maneuver and jump at 1, and then everything else was put into armor and defense.

It turned out that anything short of another similar ship was useless attacking it. Think of it as the Traveller version of the planet destroying carrot in STOS.

The spinal mount would one-shot most smaller ships, and even against something similar could deal some damage.

 

[aramis]

Which is covered by the surface-internal-crittical pathway/

Does a spinal mount cause the firing ship to recoil?

Any PA will generate force. All the official spinals I've seen have been some form of PA... noting that the meson gun is still a particle accelerator...

Unless, of course, they're some gravitic system; even then, given that Traveller gravitics do impart inertia via T-Plates (at least in MT, TNE, T4, T5)... a gravitic accelerator probably also should impart inertia; and by that token, should be pushing on something in return.

IMTU, that's the local massive body...

 

[Badenov]

With High Guard, one of the things I came up with was the "All or nothing" battleship. This was a design that had the most powerful spinal mount weapon you could get, enough power to run it and let the ship maneuver and jump at 1, and then everything else was put into armor and defense.

It turned out that anything short of another similar ship was useless attacking it. Think of it as the Traveller version of the planet destroying carrot in STOS.

The spinal mount would one-shot most smaller ships, and even against something similar could deal some damage.

I went the other way in ship design, I gave the ship a big enough plant and M Drive to have Agility 6, pushing the to-hit number for meson spinals up to 9, making it a challenging target, if not impossible, but I went low-end on the spinals with a J. But that got the ship down to 20,000 tons, and with max armor and max nuke dampers and sufficient meson screens to ignore 100T meson bays it basically ignores anything less than spinals.

Final USP is BC-L126CJ3-E03900-009J0-0 and costs 40,264.63 MCr for comparison. I will work out how to fit a T spinal and retain the agility since that has a meaningful benefit. If I am going big, I will probably push the meson screens up to 9 so even spinals have a challenge.


So the ship class, btw, is a total guess. I don't know that there's any sort of formal guidance on what tonnage goes with what class, but I felt fast+armored+pretty heavy guns fit with a battlecruiser.

 

[Spinward Flow]

I will work out how to fit a T spinal and retain the agility since that has a meaningful benefit.

The argument has been made (and I agree with the analysis) that Meson-N is a superior option to a Meson-T (if you're working @ TL=15). It's not an obvious thing looking at the meson spinal table, but the Meson-N can be mounted into a smaller (and therefore cheaper!) hull ... which creates knock on effects of increasing the number of hulls (and thus spinal mounts) that can be fielded for an identical budget spent on military line items.

The Meson-N therefore fulfills the "quantity has a quality all of its own" promise, relative to the Meson-T option.

 

[Badenov]

With High Guard, one of the things I came up with was the "All or nothing" battleship. This was a design that had the most powerful spinal mount weapon you could get, enough power to run it and let the ship maneuver and jump at 1, and then everything else was put into armor and defense.

It turned out that anything short of another similar ship was useless attacking it. Think of it as the Traveller version of the planet destroying carrot in STOS.

The spinal mount would one-shot most smaller ships, and even against something similar could deal some damage.

So, the heavy version is 98,336.11MCr and 50,000 tons, not terrible, and USP BH-P126BJ4-E09900-009T0-0. Meson screen 9 will make the J mesons much less effective and agility is still 6, for a -5 to be hit. Sadly, I had to cut the Marine complement down to 660 (the other had nearly 800), but I wanted to cram it into 50k tons to keep it in the target size DM.

It's interesting that unlike RL battleships, HG heavily armored warships are not vulnerable to tiny torpedo boats and thus do not need a screen. Basically, there's no reason to build anything other than the big battlewagon.

 

[Badenov]

The argument has been made (and I agree with the analysis) that Meson-N is a superior option to a Meson-T (if you're working @ TL=15). It's not an obvious thing looking at the meson spinal table, but the Meson-N can be mounted into a smaller (and therefore cheaper!) hull ... which creates knock on effects of increasing the number of hulls (and thus spinal mounts) that can be fielded for an identical budget spent on military line items.

The Meson-N therefore fulfills the "quantity has a quality all of its own" promise, relative to the Meson-T option.

This seems to be the case. In fact, I can build a Meson N ship for very nearly the same cost as the original Meson J ship, though it didn't have the Meson J's ship's huge Marine complement (I pared down the J's huge Marine detatchment and it brought the cost down considerably as well as sliding down a size class to hull K, making it slightly harder to hit, and bumped the meson screen to 9). The intermediate still keeps the rating 9 meson screen and that N meson isn't bad. So for half the cost of a Meson T ship, the Meson N does seems to be the way to go. BB-L126EJ3-E09900-009N0-0

Final comparison looks like:

Code	Cost	Spinal	Roll vs MScr9	Bonus Hits	To be hit	Tonnage
BH-P126BJ4-E09900-009T0-0	98328.11​	T	5	19​	-5	50000​
BB-L126EJ3-E09900-009N0-0	41479.07​	N	7	14​	-5	20000​
BC-K126CJ3-E09900-009J0-0	31621.09​	J	9	10​	-6	14000​

 

[Rupert]

The only real downside is that the meson-N can't autocrit 50,000 ton ships, such as those that might carry it. A meson-T autocrits anything under 300,000 Tons. There's also a reduced penetration chance vs meson screens and a few hull forms. As it still gets a pile of juicy interior explosions and radiation hits, and more weapons for your credit it's probably still a better deal.

The meson-N hits a sweet spot for size/power requirements vs penetration of meson screens. The meson-J just doesn't (and can only autocrit fairly small spaceships).

By the way, I notice a lot of people's sample ships don't seem to use the trick of having a battery of each type of weapon to spread out weapon damage hits and slow down degradation of the main gun (I'm sure the gunners on the lasers and fusion guns find it a huge honour to be 'armour' for the spinal mount).

Edit: It looks like, ton-for-ton, an N-ship fleet gets ~1.33 times as many hits on a T-ship fleet as it takes. Compared to a J-ship fleet, the N-ships inflict ~1.5 times as many hits. However, once you count the autocrits from the N-ships they come out ahead (but they lag behind in killing J-ships). That implies that (if I've done the maths right) that you've got a rock-paper-scissors thing going on here.

 

[kilemall]

The only real downside is that the meson-N can't autocrit 50,000 ton ships, such as those that might carry it. A meson-T autocrits anything under 300,000 Tons. There's also a reduced penetration chance vs meson screens and a few hull forms. As it still gets a pile of juicy interior explosions and radiation hits, and more weapons for your credit it's probably still a better deal.

The meson-N hits a sweet spot for size/power requirements vs penetration of meson screens. The meson-J just doesn't (and can only autocrit fairly small spaceships).

By the way, I notice a lot of people's sample ships don't seem to use the trick of having a battery of each type of weapon to spread out weapon damage hits and slow down degradation of the main gun (I'm sure the gunners on the lasers and fusion guns find it a huge honour to be 'armour' for the spinal mount).

On that last point, my version has hit distribution with two weapon hits on the table- the more common probable one goes to the largest weapon available so spinal then bay then turret, and the other hit is surface only and goes smallest to largest.