Mesons and the ground combat picture

[McPerth]

I keep thinking that there would be too many targets as to protect them (ports, food storages, power plants, cities, etc...). The only defense against it would be political agreements (akin the Geneva convention) and the thread of retaliation (and so it goes when in the Rebellion rules are not kept...).

 

[Ulsyus]

When I mentioned the Voroshilef from BR earlier, the screen value it had was 11, vs the meson gun build appearing to max out the damage rating at 13 or so. When I had a look at TNE:FF&S, it seemed that I could push the meson screen rating up to 13 with enough power. So theoretically a DN with the maximum possible screen would be pretty impervious to deep battery fire if the vessel could take multiple hits each turn without any degradation in the screen value & hence defensive capacity.

This leads me to imagine siege ortillery BBs or DNs, with not much on them short of troops, a powerful meson gun and meson screen, with everything maximised for the reduction of planetary defences.

 

[mike wightman]

Unless you use FFS to build a bigger meson gun...

 

[Carlobrand]

Wouldn't you also have to consider other defenses the planet might have like orbitals, stations / bases on moons and that sort of thing?

I mean, if you need a meson screen why does it have to be ground based? Satellites in orbit could generate one presumably shielding the planet from space.

Oooh! That one makes me shudder. The meson screen's power consumption is based on the size of the ship it covers. It's basically 0.2 EP times the code times 15 of the ship's dTonnage. I don't even want to begin trying to calculate the dTonnage of a planet.

...Orbitals with limited maneuvering capacity would be at a large advantage in terms of weapons, protection, and power not having to have jump drives, might have only a minimal maneuver drive, and even possibly having reduced fuel aboard as they could normally be refueled more frequently.

Not having jump drives is the battlerider advantage. Minimal maneuver drives in a meson universe is suicide. If it weren't for mesons, you could haul planetoids into orbit and make dandy orbital warbases. With mesons on the scene, those are about as useful as medieval castles.

And layers. If a single screen fails 58% of the time, ten nested screens fail 0.4% of the time. Nest as much as needed, power is essentially "free".

I don't think you can nest meson screens. I don't see a specific, "There can be only one," rule in High Guard, but TCS in introducing spare systems clarifies that only one can be operational at a time. It'd make for an intriguing rule change to be able to have nested screens, but at the moment it's not allowed.

When I mentioned the Voroshilef from BR earlier, the screen value it had was 11, vs the meson gun build appearing to max out the damage rating at 13 or so. When I had a look at TNE:FF&S, it seemed that I could push the meson screen rating up to 13 with enough power. ...

Unless you use FFS to build a bigger meson gun...

I really have to get my hands on FF&S.

 

[Ulsyus]

I really have to get my hands on FF&S.

Which version? I've used the TNE edition a lot given the need for play. I have the T4 version, but as we didn't play that I didn't get around to building design spreadsheets for that one.

If you were going to pick one of them, I'd recommend T4 as it's closer to T5. Then again, we could offer or lobby to assist with testing the BCS design process...

 

[mike wightman]

The only problem with T4 FF&S is having to reformat every single formula...

 

[rancke]

I keep thinking that there would be too many targets as to protect them (ports, food storages, power plants, cities, etc...). The only defense against it would be political agreements (akin the Geneva convention) and the thread of retaliation (and so it goes when in the Rebellion rules are not kept...).

If there are still active deep meson sites on the world, any combat vessel that gets within range of the surface would be concentrating its fire on those for the brief time it survives.


Hans

 

[robject]

I don't think you can nest meson screens. I don't see a specific, "There can be only one," rule in High Guard, but TCS in introducing spare systems clarifies that only one can be operational at a time. It'd make for an intriguing rule change to be able to have nested screens, but at the moment it's not allowed.

The presence of an operating Nuclear Damper field counteracts the effects of other Nuclear Dampers. Damper fields do not overlap.

Meson Screens apply a variant of the damper principle which creates a volume within which energetic mesons cannot decay. (T5-397)

It appears as though meson screens cannot be nested. On the other hand, globes (e.g. black globes) can be nested. I've logged the issue for consideration re planetary assault.

 

[Xerxeskingofking]

If there are still active deep meson sites on the world, any combat vessel that gets within range of the surface would be concentrating its fire on those for the brief time it survives.


Hans

can you target a deep meson site? I was under the impression they were sited in such a fashion that the only way to deal with them was either to already know exactly where it is or destroy it's targeting links.

 

[robject]

can you target a deep meson site? I was under the impression they were sited in such a fashion that the only way to deal with them was either to already know exactly where it is or destroy it's targeting links.

There's probably ways to get tactical kills. Triangulation could also tell you exactly where it is -- if it makes three shots to three different targets, for example. I suspect neutralizing them would be a major consideration.

 

[epicenter00]

There's probably ways to get tactical kills. Triangulation could also tell you exactly where it is -- if it makes three shots to three different targets, for example. I suspect neutralizing them would be a major consideration.

I wonder if you really can triangulate Meson guns. Mesons do not meaningfully interact with matter until they decay which is what allows Meson guns to fire through matter. Would they leave a telltale trail upon firing?

I get the impression they wouldn't - if they left a reasonably easily-tracked firing trace, there'd be no point to deep-siting Meson guns. All that planetary crust would only protect against more conventional weapons, but any "real" navy (the thing which deep-site Meson guns are presumably intended to defend against) would have Meson guns of their own at which point, again the deep-site Meson gun would become as useful as a medieval castle.

I guess you could have Meson gun fire be trackable - but then Meson guns would adopt a kind of "shoot-and-scoot" tactic similar to modern-day mobile artillery. Large Meson guns mounted on enormous anti-grav "sleds" of some sort, zipping around networks of tunnels deep under the ground. However, unless I am seriously mistaken, canon deepsite Meson guns appear to be static installations.

 

[Carlobrand]

There's probably ways to get tactical kills. Triangulation could also tell you exactly where it is -- if it makes three shots to three different targets, for example. I suspect neutralizing them would be a major consideration.

How do you triangulate a ghost particle?

... However, unless I am seriously mistaken, canon deepsite Meson guns appear to be static installations.

Invasion Earth offers the intriguing addition of mobile planetary defense regiments - shoot-n-scooters. Since the fixed sites have a limited range for affecting ground troops (with no good reason that I can think of), they introduced a mobile unit that could move around the board (planet's surface) to cover places you might not have covered while allocating your fixed sites at the beginning of the game.

It is possible the designers were thinking of a purely missile-based PD unit for that role, but missiles aren't real effective in High Guard combat. They can scrub weapons and prompt an attacker to back off for a while for repairs, but they can't really take out any reasonably armored space target. (Which is an odd thing for a contact-fused nuclear device.) So, I harbor the fantasy that these represent vehicle-mounted meson projectors of the same power and size as light-cruiser spinal mesons. BIG vehicles, on the concept of the Schwerer Gustav or the Paris Gun, but grav-mobile.

http://en.wikipedia.org/wiki/Paris_Gun
http://en.wikipedia.org/wiki/Schwerer_Gustav

 

[Xerxeskingofking]

I wonder if you really can triangulate Meson guns. Mesons do not meaningfully interact with matter until they decay which is what allows Meson guns to fire through matter. Would they leave a telltale trail upon firing?

I get the impression they wouldn't - if they left a reasonably easily-tracked firing trace, there'd be no point to deep-siting Meson guns. All that planetary crust would only protect against more conventional weapons, but any "real" navy (the thing which deep-site Meson guns are presumably intended to defend against) would have Meson guns of their own at which point, again the deep-site Meson gun would become as useful as a medieval castle.

I guess you could have Meson gun fire be trackable - but then Meson guns would adopt a kind of "shoot-and-scoot" tactic similar to modern-day mobile artillery. Large Meson guns mounted on enormous anti-grav "sleds" of some sort, zipping around networks of tunnels deep under the ground. However, unless I am seriously mistaken, canon deepsite Meson guns appear to be static installations.

if a meson screen causes a shot to decay early, and this shot travels in a straight line, then tracking the shot back to roughly where it came form should be possible ("ok, it shot at the Dautless on a bearing of 221.3, and at us of 219.2....that should put the gun about here
")


but I don't think that you could localise it precisely enough to score a hit. whats the max range of a meson spinal? say you could locate the target to within a minute of arc (1/60th of a degree), how big a box would be looking in?

 

[Reban]

but I don't think that you could localise it precisely enough to score a hit. whats the max range of a meson spinal? say you could locate the target to within a minute of arc (1/60th of a degree), how big a box would be looking in?

And you'd need to estimate or guess the range that the shot came from to figure out what the depth of your firing point is.

But how you actually do counter battery fire is not to fire back at a single point with a single gun but to call a barrage down on the area you know the shot came from.

I think Striker describes the surface effect of a meson gun as leaving broken ground. Do that with several meson guns at a depth below the ground and you are churning up a lot of earth and causing a lot of structural damage to the deep meson site (hopefully).

I can see a role for a battery squadron of small hulls fitted with meson guns in bays or spinal mounts, part of whose job it is to conduct counter battery fire on deep meson sites once detected and localized. You can also use them for ground support or general barrage work.

 

[Xerxeskingofking]

And you'd need to estimate or guess the range that the shot came from to figure out what the depth of your firing point is.

But how you actually do counter battery fire is not to fire back at a single point with a single gun but to call a barrage down on the area you know the shot came from.

I think Striker describes the surface effect of a meson gun as leaving broken ground. Do that with several meson guns at a depth below the ground and you are churning up a lot of earth and causing a lot of structural damage to the deep meson site (hopefully).

I can see a role for a battery squadron of small hulls fitted with meson guns in bays or spinal mounts, part of whose job it is to conduct counter battery fire on deep meson sites once detected and localized. You can also use them for ground support or general barrage work.

assuming you have enough separation between you and your other triangulation points, you'd work out the depth anyway, as it'd be where the lines cross, which would be a point inside the planet.

anyway, to plug some numbers into my own question:

max range, in MgT, appears to be about 50,000 KM (or at least, they stop counting at that range).

a error of 1 MOA (1/60th a degree) in targeting gives us a box about 2.3 KM wide and deep, or roughly 12 cubic kilometres in which your deep meson site is located.

how big is a deep meson site? no idea. but lets just say it's nice and big, 100,000 D-tons, with all the support facilities, defensive meson screens, emergency power generation, ect. I did the maths, once, to work out how big 100,000 Dtons is, and the answer is actually about the size of the old Worlds Trade Centre towers.


12 km³ is 12 billion cubic meters. our 1,400,000 m³ meson gun fits something like 700 times (714 by my maths, but I'm using 14m³ to the dton as per MgT rules, which I know is rounded off somewhat compared to other editions). its got a fair amount of space to hide in.


the blast radius for the meson spinals was, what, 250m radius? that's a sphere with a volume of 65,450,000m³ (rounding up, slightly). you'd need....183 shots of that size to completely cover the possible volume.

now, in reality I accept you're going to get a hit with a lot less shots than that, since you don't need to cover the whole space, just hit the meson site. but still, it'd take squadrons firing in volleys to catch and kill each gun in a reasonable time scale, and if a planet has a dozens of even hundreds of guns.........

 

[mike wightman]

That's about a factor of 10 too high tonnage wise.

You can build a 20kt battle rider that can fly around space with the biggest spinal meson gun, why not just burry it underground rather than build a 100,000t installation?

 

[Xerxeskingofking]

That's about a factor of 10 too high tonnage wise.

You can build a 20kt battle rider that can fly around space with the biggest spinal meson gun, why not just burry it underground rather than build a 100,000t installation?

ok, so its 10 KDt. that's 85,714 that can fit into that 12 Km³ box. the target has gone form "small" to "tiny"


I just picked 100,000dton as A Nice Round Number that happened to have a memorable real world reference size.

 

[aramis]

if a meson screen causes a shot to decay early, and this shot travels in a straight line, then tracking the shot back to roughly where it came form should be possible ("ok, it shot at the Dautless on a bearing of 221.3, and at us of 219.2....that should put the gun about here
")


but I don't think that you could localise it precisely enough to score a hit. whats the max range of a meson spinal? say you could locate the target to within a minute of arc (1/60th of a degree), how big a box would be looking in?

Sine(0.1666)*range

Given a max range of 75000km (from t20), that gives a one with a radius of 21.81 km and length of 750000km. That's a volume of 37382180.514 cubic km.

 

[Carlobrand]

MegaTrav wants to use the neutral pi meson for this function. There are others types out there, but that seems to be useful for decaying into something that has a pretty lethal effect. The neutral pi meson decays into gamma rays.

Key points:

The meson gun implies the existence of a meson screen, because there needs to be a way to keep the meson in existence while it's being accelerated to relativistic speeds in the gun.

Neutral pi has a mean lifetime of 8.4×10⁻¹⁷ seconds. For it to have a range of - 750 thousand kilometers? - you've got to accelerate the puppy up pretty absurdly close to the speed of light: within something like 1x10^-33 or 1x10^-34 percent or so, my cheap calculator gets hinky in that range. The energy needed to accelerate a pi meson to that velocity is ...

...wait, that can't be right. I'm getting gigajoules to get a single pi meson up to the needed speed.

Okay, math fail. Either I'm not doing it right or we're only getting a relative handful of gamma photons at the explosion site with the power we have available. Absurdly powerful gamma photons, at energy levels that I don't even know what they'd do when they hit an atom, but only a relatively small number. Or else that relativistic business is crap and the meson beam uses an extrudable screen to deliver the mesons to the detonation site. I think I may have just killed the meson gun.

So, I'm putting that line of thought to the side for the moment.

Okay then, meson hits your screen and prematurely decays to gamma. You've got your screen, you've got a region of very high frequency gamma rays emanating from a part of it. Striker does not describe the meson blast as emanating from a single point; it's a region in which everything dies. Ergo, the mesons are not a line but more a narrow cone, with the idea that when they reach the desired range they'll turn into gamma there. Won't be all at once - there's a half-life business? So you end up with - a teardrop? - if it went off where it was supposed to. However, it doesn't. It meets the screen and decays there and you've got a disc emanating gamma outside your ship, going forward, meeting your armor, heating it up but too dispersed to do any real damage.

Now you've got to take that and calculate a bearing from it? You'd need hull sensors in the affected region, no? You've got to detect what part of the hull is encountering unusual levels of gamma, and you need to do it with enough detail that your computer can glean a bearing from that. That's - I don't see how you get a bearing from that accurate enough to tell you more than that it came from somewhere beneath you.

 

[rancke]

Oh, no no no. Meson guns don't use mesons! Because that would mean that someone who knows about the laws of physics would be able to prove that there's no way meson guns could work like they're described. Meson guns use particles discovered by Dr. Kevin Meson in 2203 AD [Not canon]. Or something like that.


Hans