Ground Weapons VS Starships

[Solomani666]

The Ground Forces Weaponry Against Starship Scale Targets found on page 73 of Mercenary seem somewhat ambiguous. Part of the paragraph says that the DAMAGE should be divided by 50 and the example clearly states that the DAMAGE DICE should be divided by 50.

Which seems right to you?
When tanks and troops are firing at a starship, should you...

Add the total damage dice, divide by 50, then round down...
...or...
Add the total damage, divide by 50, then round down.

 

[Jeraa]

Since it just says "damage", either one could be correct. But, with the weapon damages listed, scaling the damage points seems to make more sense.

 

[apoc527]

None of the above. The 50x modifier is insane. If I have to choose, I would say the damage, not the dice.

 

[locarno24]

I never found it much of a problem. The big thing that allows you to kill a starship is massed firepower.

High Guard:

Gaining a +4DM bonus to hit anything on the starship-scale, ground force weaponry must divide its damage by 50 before comparing it to a starship-scale target’s armour. Because a single weapon will, obviously, be unable to punch though armour it is possible for multiple weapons to all target the starship simultaneously, and the cumulative effect can inflict damage. Every additional ground weapon beyond the first can add half its damage dice to the total before dividing the total by 50 in order to calculate damage

Meaning that something like 30-odd autocannons (i.e. something like a company-strength force) firing on a single armour 6 ship should do something.

Also bear in mind that most 'civilian' ships (and even a few paramilitary ones) are essentially unarmoured.

Persuading the crew of a trader not to lift off is a lot easier than stopping an invasion-class troopship reaching its landing site.

 

[Jeraa]

Massed firepower isn't the problem. Its that, if the rule is to scale the damage dice, there is no single weapon in any of the books (except starship weapons) that can even scratch a starship. Not even a small, 10 ton, unarmored ship.

Its not stated out, put the table on page 110 of the Central Supply Catalog lists the damage of an 800mm weapon as doing 28d6 damage. Divide the damage dice by 50 and round down like the example shows, and not even this huge weapon can scratch even the smallest ship.

http://en.wikipedia.org/wiki/File:80_cm_Gustav_shell_compared_to_T-34.jpg The link is to a picture of an 800mm shell. In the background is a Russian T-34 tank. Now you tell me that shell won't even scratch a 10 ton unarmored ship...

 

[DFW]

the damage of an 800mm weapon as doing 28d6 damage. Divide the damage dice by 50 and round down like the example shows, and not even this huge weapon can scratch even the smallest ship.

It isn't about the size of the projectile but, the kinetic energy. So, get the velocity at point of impact of that shell and its mass then we can compare. Otherwise, it's meaningless.

 

[Jeraa]

Was fired from this.

High Explosive
* Weight of projectile: 4.8 t (4,800 kg)
* Muzzle velocity: 820 m/s
* Maximum range: 48 km
* Explosive mass: 700 kg
* Crater size: 30 ft (10 m) wide 30 ft (10 m) deep.

AP Shell
The main body was made of chrome-nickel steel, fitted with an aluminum alloy ballistic nose cone.
* Length of shell: 3.6 m
* Weight of projectile: 7.1 t (7,100 kg)
* Muzzle velocity: 720 m/s
* Maximum range: 38 km
* Explosive mass: 250 kg
* Penetration: In testing it was demonstrated to penetrate 7 meters of concrete at maximum elevation (beyond that available during combat) with a special charge.

 

[DFW]

Was fired from this.
AP Shell

* Weight of projectile: 7.1 t (7,100 kg)
* Muzzle velocity: 720 m/s

This gives (maximum) at muzzle, 1,840,320,000 joules of energy for that weapon.

A fast, small craft going from Earth to an outer planet has to be able to withstand at least 20,976,400,000 joules in case of micro-meteor hit. Or, ~11 times as much kinetic energy.

There ya go. It bounces of the hull of a small craft.

 

[Jeraa]

Except ships can't just ignore micro meteors, or the self-sealing armor option (page 106 of the core book) would be entirely pointless.

And encountering a micro-meteor sounds like the Collision! encounter on page 140 of the core book. So 2d6 damage.

And just noticed micrometeorites are even mentioned as a collision source on the table on page 139. And if that 800mm rounds damage was scaled by points, it would do an average of 1.96 damage to a ship. Compared to a micrometeor doing 2d6, that sounds about right.

 

[rust]

Besides, depending on the type of AP warhead, the 250 kg of explosive
could add considerably to the kinetic energy - even old fashioned TNT
would generate more than 1 Gigajoule of energy from 250 kg of the ex-
plosive.

 

[DFW]

Except ships can't just ignore micro meteors, or the self-sealing armor option (page 106 of the core book) would be entirely pointless.

No the self sealing option if in case you get holed by a weapon. People aren't self sealing so if you have micro-meteors flying through the hull of a small craft you don't have living people or working drives and what not.

Pretty obvious when you think about it.

 

[DFW]

Besides, depending on the type of AP warhead, the 250 kg of explosive
could add considerably to the kinetic energy - even old fashioned TNT
would generate more than 1 Gigajoule of energy from 250 kg of the ex-
plosive.

Of course. However, lacking the data as to type of charge (shaped or not) how much of the shell (mass) behind the charge actually gets pushed away (backwards away from the target) by the blast, etc. We can only go by kinetic energy we can calculate.

 

[Jeraa]

The self-sealing option specifically mentions micrometeroid impacts. If there is an armor option that seals those holes, a hole needs to be made in the ship first.

Pretty obvious when you think about it.

 

[apoc527]

A fast, small craft going from Earth to an outer planet has to be able to withstand at least 20,976,400,000 joules in case of micro-meteor hit. Or, ~11 times as much kinetic energy.

There ya go. It bounces of the hull of a small craft.

Ok, that is the problem with Traveller if you use this kind of reasoning. I find it highly improbable that surviving that much energy is EVER possible, let alone through some kind of hull material alone. The ship would be so heavy that it would take more power than a fusion plant can provide to ever lift off from a planet.

It's frankly just plain silly. I think I'll just go play Star Wars. At least the math in that setting is more reasonable!

 

[DFW]

Ok, that is the problem with Traveller if you use this kind of reasoning. ...

It's frankly just plain silly. I think I'll just go play Star Wars. At least the math in that setting is more reasonable!

Well, it isn't "a kind of reasoning". It is the rules of Trav as written. If you find Newtonian physics "silly" because Trav allows continuous accel travel, I guess you need to change the basics of the game.

 

[barnest2]

It's frankly just plain silly. I think I'll just go play Star Wars. At least the math in that setting is more reasonable!

Yeah, 200 gigaton secondary weapons=reasonable...

 

[DFW]

It's frankly just plain silly. I think I'll just go play Star Wars. At least the math in that setting is more reasonable!

I didn't catch that part until now. Doesn't Star Wars use basic math & basic physics? What would they use instead?

 

[apoc527]

That's my point. If Traveller is supposed to represent harder sci-fi (where Star Wars is like a raw egg), then how can we believe in DFW's position, no matter how many times he restates it?

Not only does it make no sense, but it's bad for gameplay. The only plausible explanation would be that all Traveller hulls are made out of that indestructible transparent material that is used in Ringworld and other Niven Known Space stories...but that stuff is like TL 20 (or should be).

 

[apoc527]

Ok, that is the problem with Traveller if you use this kind of reasoning. ...

It's frankly just plain silly. I think I'll just go play Star Wars. At least the math in that setting is more reasonable!

Well, it isn't "a kind of reasoning". It is the rules of Trav as written. If you find Newtonian physics "silly" because Trav allows continuous accel travel, I guess you need to change the basics of the game.

I just think your assumptions are way, way off. And clearly I'm not the only one who disagrees with you. Ultimately, your particular vision of Traveller would utterly ruin the entire game for me, so IMTU, The DFW Travel Assumptions are hereby declared invalid. Micrometeorites are detected and avoided or destroyed, not simply rammed by ships with godlike levels of toughness.

 

[barnest2]

The thing is, someone worked out in another thread that micro-meteor impacts are incredibly rare. for them to punch a hole is believable, but for the ship to be completely resistant breaks SOD.
So having them on the collision table makes sense, no?