• Welcome to the new COTI server. We've moved the Citizens to a new server. Please let us know in the COTI Website issue forum if you find any problems.

Nukes and the small ship universe

Carlobrand

SOC-14 1K
Marquis
Ran into an interesting dilemma while fiddling with High Guard weapons rules. It boils down to this: the big ship universe doesn't work, at least not for naval combat.

We know the problem with mesons, that's not new. The problem is nukes. I've suggested before that the basic canon turret-launched nuclear missile is equivalent to the old Davy Crockett nuclear warhead, which was a 10.75-inch diameter, ~15.7 inch long, 23 kg (depending on source) warhead with a 10.75" diameter spherical implosion device that (again, depending on source) gave from 0.006 to 0.010 kt - 6 to 10 tons TNT equivalent. Reason is simple: that's the size of contemporary nuke that does the kind of damage a High Guard nuke does. 0.005 kt in Striker produces a 76 penetration, while the 0.01 puts out 82. However, the Davy Crockett was made intentionally inefficient to reduce blast to something that could be fired from an artillery piece without putting the gun crew at risk. A fully optimized warhead of that size could reach 1 kt for the same amount of plutonium, and something 100 times more powerful is going to come away with penetration values in the 90's, possibly 100 or more. At those values, armor is pretty much irrelevant: even a fully armored buffered planetoid is going to get a crater several meters deep blown into it. It's a bit hard to argue a space force wouldn't optimize their warheads when confronted with heavily armored targets. Others, arguing from the Black Globe rules, have suggested the warhead might be even larger. This of course assumes an impact detonation, but there's no reason to assume otherwise if the HE missiles are successfully impacting with the same odds.

Missiles at that point become about as deadly as a meson spinal. For a Factor 9 missile salvo, about 1 salvo in 6 will penetrate a Factor 9 nuclear damper, and agility is not a lot of help to battleship-size targets. The game becomes about being small, agile, and numerous, the new "battleship" becomes something about the size of a destroyer, and fighters become very nasty indeed until the dampers become too big a factor and the computers become too advanced to be cost-effective for them. You end up with a "small ship" navy, with larger ships relegated to support roles where they're less likely to face attack by nuclear missiles.

Traveller dials down the nuke quite a bit in order to be able to offer big ships. Dialing them back up makes an interesting rationale for running a small ship universe.

You could "dial-a-yield" the missile, making it useful for either space combat or planetary bombardment. A very low yield nuke is better for a orbital bombardment missile because, coming down from above, it will kill most armored vehicles on impact, as well as incapacitating or killing most exposed ground troops within a football field's length or two of the target unless they're in TL 14+ combat armor or better, without as much wasted force as a larger nuke. Most grav MBTs and APCs would be designed to survive indirect nuclear attack as long as they're at least in the outer half of the primary radius and would maintain enough spacing that only 1 or 2 would be caught in the lethal inner half of any one attack, so a bigger boom does not usually accomplish much on the ground beyond civilian casualties and ravaged terrain. However, one does prefer to have adequate punch for space combat.
 
Sorry to derail your thread right away, but briefly, what is the problem with mesons?

in essence, the problem is that a large meason spinal is able to kill or cripple pretty much any large ship regardless of size, screens or armour. Games with these meson basically come down to the first spinal hit, which decides the battle.


So the most the most effective ship, based on the rules, is a cruiser sized (70,000 Dtons or so) ship armed with a large meason, and not, as canon says, big battleships that are 200,000-500,000 dtons, which are massively more expensive, but don't actually offer much better combat proformance.

the above is all based on classic travellers combat rules, and other editions give different answers due to different mechanics.
 
Mesons aren't as all powerful as that. Yes they do cripple, but between staying at long range, meson screens, and agility/hull design, they aren't so easy to hit with.

The bigger limitation of HG battleships is the one spinal weapon per hull rule, and lack of power allocation.

2-3 spinals generating that many more hit opportunities wrapped in ever cheaper defenses per spinal, plus power allocation to do whatever mix of weapon vs. maneuver vs. defense, would make the bigger ships more flexible and proportionately deadly, rather then just being a target whale/fiscal white elephant.
 
That's why you go with an "all or nothing" ship mounting a meson spinal weapon, if you are going that route. The ship mounts no other weapons to speak of and has passive defenses maxed out to try and mitigate the effect of similar weapons against it. It's more like the Star Trek doomsday machine than a Star Wars Death Star.

You mass fire these ships on a single target, say 5 + against one to ensure at least one serious penetration and crippling of the target in the first salvo. You switch targets to a new victim, and it boils down to how many all-or-nothing meson gun ships you have versus how many they have.

All active defense of this sort of ship is by smaller ones that don't mount a spinal weapon at all but act more like escorts with weapons and such to make penetrating their screening of the meson gun ships difficult.

Thus, you end up with more of a small ship universe this route too.
 
Spinal Mesons for all practical purposes, kill whatever they hit. The dark side is that they're lousy shots. But if they DO connect, the target is pretty much combat incapable.

HG is a crit centric system. Ships > 1000 tons are crit immune to everything but spinals. Without crits, you can't reduce armor. Without reducing armor, all you can do is really ding fuel and burn off weapons. These don't really "kill" the ship, but they certainly take it out of the fight. But the core of the vessel is mostly intact, and can flee to live another day.

Mesons cheat in several ways. First, the ignore armor, which means they get to roll on the meaty parts of the damage chart. Second, they're considered radiation damage, so they get 2 rolls for the price of one. Finally, they roll on the interior explosion table. That's just for a normal meson.

Spinals get lots of free crits, and crits crack the armor, and kill the ship.

Which is a reason to not ignore PA spinals. PAs are much easier to hit with. Honestly, the PA spinal is the most idiomatic of Sci Fi weapons in terms of cinematic effect. You can easily see a couple of large ships with PA spinals firing at each other. The armor and size differential may make the ships crit proof at the beginning, but the hits keep coming, and the armor starts breaking, and the then the crits start rolling up. A ship can take a couple of spinal PA hits, but it will break in time under fire. In contrast to the one hit, one kill nature of a Meson.

So, you can see a Meson spinal ship against a PA spinal ship -- it's just a matter of luck as to whether the Meson ship can land a shot on the PA spinal ship before the PA ship cracks the Meson ship like an egg.

I should run some sims to throw a meson fleet against a PA fleet. I bet the PA fleet wins out, but have to run the math. PA fleet gets more hits, early on, which can reduce the meson fleets spinals, making them even more difficult to hit with.
 
Either way, the best design is one that mounts that massive spinal weapon and nothing else. Your ship is far cheaper to build and man so you can get more of them for a set amount of cash. The passive defenses for the most part don't require crew and are relatively cheap to add.

The expensive ships are the escorts, but targeting these just gets all your big ships blow out of space. So, it becomes a slogging match between the spinal all-or-nothing ships. Without looking it up, which does better at longer range, the meson gun or particle accelerator? That would determine your choice as the longer ranged weapon could simply stand off and cream the shorter ranged one.
 
A TL15 BB with factor 15 armour is immune to PA crits, immune to all bay and turret weapon damage bar pulse laser batteries, and if it sticks to nuclear dampers only half the nukes that are fired at a BB will hit, 17% of these will penetrate the damper, and even then half of them will inflict no damage due to rolling 7+ on the 2D damage dice.

Fire 100 missile bays at a BB - requiring at least 100,000t of opponent shipping, and you can expect a grand total of 5 damage rolls on the surface explosion table and 5 on the radiation. Weapon hits and a bit of fuel, the spinal reduced by at the most 2 factors (unless the BB designer is stupid and hasn't maxed out the USP to soak hits).

Have you considered comparing the efficacy of 1900t escort class missile frigates, 19,000t missile light cruisers, and 74,000t missile heavy cruisers.

Now introduce some battlerider versions of the above so they can carry maximum armour and screens.

There are some balance issues with HG, here are a couple of house rules I have tried out to help even things up:
bay weapons do not suffer the +6DM on the damage table (and yes I would still grant the nuke bonus -6DM making them just capable of getting an interior explosion on an armour 15 ship) - note you do need to circle weapon factors that are bay weapons

I have yet to find a satisfactory fix for spinal PAs - the closest to a workable solution is the PA gets a damage table -1DM per factor above 9.
 
Without reducing armor, all you can do is really ding fuel and burn off weapons. These don't really "kill" the ship, but they certainly take it out of the fight.
Agreed, but regular hits can be repaired (or refuelled) during the battle. Only spinals can knock ships out.
 
Either way, the best design is one that mounts that massive spinal weapon and nothing else. Your ship is far cheaper to build and man so you can get more of them for a set amount of cash.
Skip the armour and the ship becomes much smaller and hence cheaper. That is even better unless the enemy has some nukes or PAs.

There is no single best ship against all opponents...
 
The armor is best so you can try and make your all-or-nothing ship last a bit longer. Armor is cheap. You don't even need much of a maneuver engine since if the enemy is in range so are you and you aren't really trying to avoid them.
 
The US 8 inch nuclear round, with a diameter of less than 8 inches, had a variable yield of between 1 and 6 kilotons, depending on the plutonium pit used for the warhead. Warhead weight was considerably less than the circa 200 pounds of the carrier shell weight. The US 155mm nuclear round was less than 6 inches in diameter, with a variable yield of between 0.1 and 1 kiloton, again depending on the plutonium pit used. Earlier rounds using a gun-type U-235 warhead were longer and heavier than the standard 95 pound HE round, with weights of about 134 pounds because of the longer shell for the gun-type assembly. Yield was about 1 kiloton.


If you are allowed a diameter of 10.75 inches, without the stress of being fired from a cannon, putting enormous G-stresses on the warhead, there should be no problem getting a yield of 5 kilotons. As the rounds mentioned were mainly designed in the 1950s, you might be able to get 10 kilotons with a more modern design, with maybe 15 kilotons if you are allowed a little bit more weight.

If you are looking at much higher yield weapons, a reasonable rule of thumb is 1 kiloton per pound of warhead weight, with very high yield weapons, say 5 or more megatons being more efficient than that. The 9,000 pound warhead of the US Titan 2 missile was rated at 9 megatons minimum, and that obviously included the weight of the re-entry vehicle and probably some decoys.
 
Meson guns and jump factor three were the Terran trump cards against the Vilani.

If, assuming Mongoose commits to jump that way, meson guns can only be spinal mounts, atomic bombs may be more attractive at the adventure class level.
 
Anyway, the thesis is flawed in that smaller ships 9 or below are vulnerable to turret and bay nuclear weapons with the automatic crit rule piling on damage in addition to their -6DM related crits.
 
Anyway, the thesis is flawed in that smaller ships 9 or below are vulnerable to turret and bay nuclear weapons with the automatic crit rule piling on damage in addition to their -6DM related crits.

I don't see the flaw here. I think if it's a question of seeing your big ship get killed and seeing your small ship get killed, it hurts less to lose the small ship. You can field close to a couple hundred DEs for the price of a dreadnought. Both can carry a damper, and it's just as effective. The two hundred DEs are harder to hit, being smaller. They can each carry a solid battery of missiles if they focus there. Lose one thousand-ton ship, you still have 199 others. Lose your 200 kiloton dreadnought, you just lost 200 kilotons of ship and all the weapons it carried. If a nuke is powerful enough to take any ship into interior explosion range - and the occasional crit - then you really don't want all your eggs in one basket.

I'd make the things more in the 1200 dTon range, so I can have a couple of turrets to turn to something besides nuking other ships, make them a bit more useful for things like taking pot shots at fleeing cutters without wrecking the cutter and its occupants, but they're still outnumbering the DN by 150 to 1, and they're cheaper to lose.

Also note, per High Guard, the automatic crit rule says, "These critical hits are reduced in number by one for each two factors of armor the target ship has; round odd numbers down." Just 10 factors of armor will prevent ships of 400 dTons and up from taking auto-crits from bay weapons. Auto-crits aren't really a factor against craft above a certain size, depending on their armor level.
 
Missiles at that point become about as deadly as a meson spinal. [...]

Traveller dials down the nuke quite a bit in order to be able to offer big ships. Dialing them back up makes an interesting rationale for running a small ship universe.
[...]

Missiles and lasers are generally "supposed" to be quite effective for space combat, and other weapons are generally "supposed" to have niche applications.

And, at the same time, Traveller has a Big Ship background, but a Small Ship focus.
 
Occurs to me that an interesting alternative is to divide the fleet into 3 groups: a screen, a line, and a reserve. Line ships can only fire mesons through their own screen and can only be targeted by mesons while their screen is intact.
 
That would only strengthen meson dominance.

With a screen meson ships can't be hit by missiles or PAs, so don't need armour. We would see ridiculous unarmoured riders with spinals, sceens and nothing more.

I see no advantage...
 
Occurs to me that an interesting alternative is to divide the fleet into 3 groups: a screen, a line, and a reserve. Line ships can only fire mesons through their own screen and can only be targeted by mesons while their screen is intact.

In naval warfare a ship unused is a ship wasted. Reserves are for land warfare.
 
Back
Top