Roug concept: Mobile anti ship guns, with illustration

[Condottiere]

I think the writer is going to have to clarify this.

I should point out, that largecraft and smallcraft weaponry are categorized as spaceship weapons.

If it is interpreted as permitting largecraft variants, then I'd park one of those vehicles in a smallcraft hold, and open both cargo hatches.

 

[PsiTraveller]

This is where the 1 hardpoint per 100 tons makes little sense. Why can't extra fire and forget missiles be attached to cargo racks on a ship, or towed behind in missile pods ( thanks for the idea Honor Harrington), to add throw weight to missile salvos ? Even strapping trucks to a cargo mount could increase throw weight.

It should be possible, but would lead to MAD spacecraft scenarios. Warships as nothing but missile shotguns hoping to wipe out an enemy in a single salvo. (4 D damage - armour * 100 000 missiles will destroy a Dreadnought) That leads to boring games.

Because ships cannot increase armour despite size of ship, a Dreadnought of 200 000 tons has the same damage reduction as a 100 ton warship. This makes them vulnerable to the damage multiplier of missile combat.

 

[Epicenter]

I think the writer is going to have to clarify this.

I should point out, that largecraft and smallcraft weaponry are categorized as spaceship weapons.

If it is interpreted as permitting largecraft variants, then I'd park one of those vehicles in a smallcraft hold, and open both cargo hatches.

It's been a problem in Traveller for a very long time, even before MongTrav.

I remember a new player in a MT game way back in the day asking, "Why is a civilian freighter's hull have vastly better armor than a TL14 grav tank? Why would anyone make a tank with such low armor when a civilian starship can have better armor? Why is a merchant ship's cheap "self-defense laser" so much better than a TL14 grav tank's main gun?" Even the argument, "because a tank is cheaper" and certainly "because the tank doesn't need it" sort of falls on its face - it flies in the face of logic. If you could armor something like a freighter that high, then why wouldn't you armor a tank even more?
Then:

Player: "Why don't people just use starship lasers in tanks and stuff in the Traveller Universe?"
GM: "Because that'd be like mounting a WW2 16-inch naval cannon on a tank."
Player: "If they could fit a 16-inch cannon on a tank and drive it around, everyone would. They can in Traveller. Why don't they? Are they stupid? Grav tanks don't worry about ground pressure."

There's been a hilarious disconnect between "starship weaponry" and "ground force" weaponry that's gone on for so long. I think MongTrav's attempts to unify it has finally brought it into stark contrast for people who have ignored it up to now.

I mean you could put something like that in your hold. We'll say it'd be like a Q-ship from the World War era. Perhaps we could assume it'd have inferior range (the spaceship gun technical wouldn't have the targeting sensors and precise stabilization to allow it to fire out to the full range) and it would definitely have a poor arc of fire since it's shooting from some cargo port. However, I'm sure it'd still have its uses. But otherwise, I don't see why you couldn't do it - and why this whole "hardpoint" and "spaces" abstract system struggles with these situations.

 

[Condottiere]

I have missile buses; they aren't small.

 

[steve98052]

A starship grade missile is mostly just thrusters and a low endurance power supply. You could build a pretty nasty system defense installation by just standing a bunch of them upright under a camouflage tarp, and sending the launch command when it's time to shoot something. The fire control is the complicated business, and that's the part of a starship missile rack that costs the money and requires a hardpoint. For ground based missiles, the ground has practically unlimited hardpoint; it's just a matter of spending the money to provide fire control for an entire salvo of missiles

Starship lasers aren't as good for system defense, except on airless worlds, because atmosphere interferes. The rules say one-tenth range, I think.

 

[phavoc]

Yeah, one would have hoped that the reboot of v2 MGT would have addressed some of these long-standing issues. I had high hopes that T5 was going to do the same thing.

I was wrong both times. (sigh)

 

[Infojunky]

It's been a problem in Traveller for a very long time, even before MongTrav.

I remember a new player in a MT game way back in the day asking, "Why is a civilian freighter's hull have vastly better armor than a TL14 grav tank? Why would anyone make a tank with such low armor when a civilian starship can have better armor? Why is a merchant ship's cheap "self-defense laser" so much better than a TL14 grav tank's main gun?" Even the argument, "because a tank is cheaper" and certainly "because the tank doesn't need it" sort of falls on its face - it flies in the face of logic. If you could armor something like a freighter that high, then why wouldn't you armor a tank even more?

I would like to point out the TL10 Model A Plasma gun could damage a ship in CT and MT. As could a 10 kilo shape charge in a TacMissile.

As for other assumptions under CT, I always assumed the Main gun on the Book 3 AFV could damage a Starship.... In that tank guns are in the 4 to 5 inch range similar to the common 5 inch Naval Cannon. Or historically Tanks were armed with Naval guns.

In Traveller terms the difference between Ship's weapon and ground weapons is range. Which the biggest controlling aspect is focal array size, thus a ship's laser probably has a significantly larger emitter array than a tanks, but both do the same damage.

 

[Condottiere]

In theory, you could add stages to missiles, or torpedoes, to extend the range.

 

[AnotherDilbert]

It's been a problem in Traveller for a very long time, even before MongTrav.

I remember a new player in a MT game way back in the day asking, "Why is a civilian freighter's hull have vastly better armor than a TL14 grav tank?

It has never been that way. In MT a basic commercial hull has armour 40. A Trepida or Zhodani Z-80 grav tank also has armour 40. You can easily build tanks with heavier armour.

Player: "Why don't people just use starship lasers in tanks and stuff in the Traveller Universe?"
GM: "Because that'd be like mounting a WW2 16-inch naval cannon on a tank."

You can. A spacecraft turret weapon is not a very large or heavy weapon. Current tanks use at least that heavy guns.
They tend to use a lot of power though.

 

[simonh]

IMHO the idea that standard civilian starship hulls are even comparable to tank armour is daft, given how small starship turrets are. If TL tank armour is 40 point on a MT scale I'd expect starship hulls to start at something like 10 points or so with starship weaponry scaled to match.

When it comes to missiles I agree based on what we know about modern missile systems the idea of a launcher in a turret that needs reloading seems anachronistic. Most missile systems consist of cell launchers as depicted in these illustrations. So how come starships have missile turret?

The best (actually least worst) answer to that I’ve come across is that missile turrets incorporate a linear accelerator that dramatically boosts up the launch velocity of the missile. It’s far from a perfect explanation, but I think it’s workable.

That doesn’t necessarily mean that designs like these terrestrial launchers have to follow the same logic. Starships are heavily volume constrained, so a linear accelerator for initial launch might make sense. For a ground-based launcher you might add an initial booster rocket stage to each missile to obviate the need for a reloadable launcher at the cost of significantly increased mass and volume for each missile. Also an atmosphere imposes limits on your launch velocities compared to a vacuum so what makes for sensible launch characteristics will be different.

Simon Hibbs

 

[phavoc]

The best (actually least worst) answer to that I’ve come across is that missile turrets incorporate a linear accelerator that dramatically boosts up the launch velocity of the missile. It’s far from a perfect explanation, but I think it’s workable.

That doesn’t necessarily mean that designs like these terrestrial launchers have to follow the same logic. Starships are heavily volume constrained, so a linear accelerator for initial launch might make sense. For a ground-based launcher you might add an initial booster rocket stage to each missile to obviate the need for a reloadable launcher at the cost of significantly increased mass and volume for each missile. Also an atmosphere imposes limits on your launch velocities compared to a vacuum so what makes for sensible launch characteristics will be different.

Simon Hibbs

That would make perfect sense... if the rules were like that. But they aren't. No acceleration boost from launching in a turret.

There's still good reasons to have full magazines. Cell launchers are great for rapid fire, but once you are done you have to retreat to port (or call up your fleet train) to reload. If you have missiles stored in cargo, then you might as well put them in a launcher so you at least have the option of draining your magazines in combat. Ammo in a cargo hold belongs in a supply ship.

 

[Condottiere]

It's an abstract design system, until you try to visualize it.

I think the design balance attempt between smallcraft and largecraft weapon systems doesn't really work.

What should have been done was to increase power requirements and increase the size of the ordnance, making using less energy intensive, smaller volume ordnance more attractive for smallcraft.

 

[AnotherDilbert]

IMHO the idea that standard civilian starship hulls are even comparable to tank armour is daft, given how small starship turrets are. If TL tank armour is 40 point on a MT scale I'd expect starship hulls to start at something like 10 points or so with starship weaponry scaled to match.

Armour 40 is about 10 cm of crystaliron or about 5 cm of bonded, so it is comparable to a current MBT. An MBT turret is smaller than a starship turret and has thicker armour, so it can be made.

I think canon is that starships are well armoured to withstand micro-meteors and radiation at high speed, and the unspecified rigours of jump space.

 

[steve98052]

I think canon is that starships are well armoured to withstand micro-meteors and radiation at high speed, and the unspecified rigours of jump space.

Exactly. If I did the math right, typical starship armor may be on the light side for resisting micro-meteors.

Consider a 1 mm sphere of stony material of density 2.5 -- it has a volume of 4/3 pi (0.5 mm)^3, or about 0.52 mm^3, and a mass of 1.3 mg.

Consider a ship on a trip to a gas giant that takes 24 hours at 2 G. It accelerates and decelerates for 12 hours each, 43200 seconds at 19.6 m/s^2, for a peak velocity of 847 km/s.

Suppose the 1.3 mg speck of rock hits at peak velocity. The kinetic energy of the impact is 0.5×0.0013 g×(847000 m/s)^2 = 466 MJ, comparable to 110 kg of TNT. That's enough to spoil your day.

Even if you reduce the speck by a factor of ten diameter, to 0.1 mm, the factor of 100 reduction in energy is still comparable to 0.11 kg of TNT, or a hand grenade worth of kinetic energy concentrated on a 0.1 mm circle of the hull.

Given that risk, it's probably a good idea to detour out of a system's ecliptic plane, even if it adds travel time.

 

[Condottiere]

The default armour would be half or quarter of a factor, rather than the hull not taking up volume.

 

[Infojunky]

Consider a 1 mm sphere of stony material of density 2.5 -- it has a volume of 4/3 pi (0.5 mm)^3, or about 0.52 mm^3, and a mass of 1.3 mg.

Consider a ship on a trip to a gas giant that takes 24 hours at 2 G. It accelerates and decelerates for 12 hours each, 43200 seconds at 19.6 m/s^2, for a peak velocity of 847 km/s.

Suppose the 1.3 mg speck of rock hits at peak velocity. The kinetic energy of the impact is 0.5×0.0013 g×(847000 m/s)^2 = 466 MJ, comparable to 110 kg of TNT. That's enough to spoil your day.

Even if you reduce the speck by a factor of ten diameter, to 0.1 mm, the factor of 100 reduction in energy is still comparable to 0.11 kg of TNT, or a hand grenade worth of kinetic energy concentrated on a 0.1 mm circle of the hull.

Given that risk, it's probably a good idea to detour out of a system's ecliptic plane, even if it adds travel time.

Or several thin layers of spaced armor.

 

[Condottiere]

Some kind of instant seal liquid that both plugs the hole and spreads the energy laterally.

 

[wbnc]

Boron Carbide ceramic with layers of Steel/Titanium foam. It's not that hi-tech fancy once ya reach the level you can build a jump drive

 

[Infojunky]

Boron Carbide ceramic with layers of Steel/Titanium foam. It's not that hi-tech fancy once ya reach the level you can build a jump drive

Gotta disperse that energy laterally between layers.

Sounds like a Plan....

 

[Condottiere]

In theory, you want the interior hollow drum to collapse under pressure.