mass drivers

[steventirey1985]

Does anyone have stats for a mass driver? What I want is something like the Centauri use against the Narn homeworld in Babylon 5. I've found several threads discussing the topic of mass drivers, but no stats.

How big would a mass driver be? How big of a rock can it hurl? How fast does the rock travel? What kind of damage can be expected? What would one cost?

The mass driver probalby can't be used against mobile targets (such as ships) but could be used against stations and for orbital bombardment. In that case, the damage could be "Plot Device", i.e. what it hits, it destroys. What would be the Area of Effect?

 

[Laryssa]

In my campaign, mass drivers are reaction engines used to move the ship around, similarly you could use a fusion torch drive as a weapon were you to get close enough.

 

[tjoneslo]

Mass Driver is a generic term, used for any artillery sized or larger magnetic linear accelerator, also know as a Gauss Gun. There have been only a few references to large scale (i.e. over 2000mm) mass drivers.

There really isn't any limit to the size of a mass driver. I've seen real life proposals to hurl 100 ton masses to the lunar surface, which means velocities over 11 miles per second. At this size we are into the duplicating strategic nuclear weapons in damage.

The limitations in Traveller would be: How large a rock do you want to hurl and how much power do you have to hurl it?

Because GURPS has a better weapons design system:
Huring a 20 ton chunk of steel requires a 1300mm barrel, this takes about 12dtons, costs Mcr30, requires 4500 (starship) EP, and does 6dx516 damage. A rock this size is between 10 and 15 tons, and does about 1/2 damage. This is in the 100 ton nuclear weapon range (i.e. very small tactical nuke). Dropping this from orbit probably doubles the damage.

I can get bigger or smaller if you would like.

 

[steventirey1985]

Just want to make sure it's not a miss-type: that does say 6dx516 damage, right? 6d what? 6d6? 6d20? Or do you actually mean d6x516 (which results in a random number between 1 and 6 x 516?)

Also, what kind of area would this effect?

As for sizes, I would really like at least 2: a small one for more precise bombardment where you don't want to much collateral damage, and a really big one for when you just don't care what gets hit and want to cause massive damage to everything.

 

[Jeff M. Hopper]

Why not just divert a small (1-10 km diameter) comet or asteroid if you want to destroy a world's biosphere?

Also, I don't see why a Repulsor battery couldn't be used to "nudge" some debris into a decaying orbit that would hit a surface installation. A possible alternative to the MMD (Massive Mass Driver).

 

[tjoneslo]

Originally posted by steventirey1985:
Just want to make sure it's not a miss-type: that does say 6dx516 damage, right? 6d what? 6d6? 6d20? Or do you actually mean d6x516 (which results in a random number between 1 and 6 x 516?)

sorry, GURPS Terminology: 6d6x516 or 3096d6.

Also, what kind of area would this effect?

According to the GURPS 3rd rules, divide damage by 4 for each 8 yards/meters, for a total of 24 yards/meters to the edge of the lethal (3d6) radius.

As for sizes, I would really like at least 2: a small one for more precise bombardment where you don't want to much collateral damage, and a really big one for when you just don't care what gets hit and want to cause massive damage to everything.

This is the small one. It has enough damage to destroy almost anything short of an armored bunker. The limit of the damage is the number of hit points in your rock.

And I got the mass of the rock wrong. In reality the rock of this size is about 6.5 tons.

I'm not sure what you'd consider large. A 64 meter EM gun, which fires a 1 million ton shell (using iron/nickel asteroids), is 6000 tons, Mcr15,000, and does 6d6x12,800 damage.

For something this size I'd use as astreroid impactor, using a 62m diameter projectile, 17 km/s impact velocity, and 8000kg/m^3 for density. This creates a crater about 2km across, and smashes buildings up to 10km away.

 

[steventirey1985]

Thanks for your help, these will do fine. With the link you provided, I got all I need. Thanks again.

 

[stofsk]

Originally posted by Jeff M. Hopper:
Why not just divert a small (1-10 km diameter) comet or asteroid if you want to destroy a world's biosphere?

Also, I don't see why a Repulsor battery couldn't be used to "nudge" some debris into a decaying orbit that would hit a surface installation. A possible alternative to the MMD (Massive Mass Driver).

Because of time. Diverting a small asteroid or comet isn't going to make it hit the planet in a speedy way, and any delay would give the planetary defenders time to react.

 

[Liam Devlin]

A small mass driver system is canon--the rock detrius ejectors of the Belt Strike LSP Mining ships used on. Using FF&S, and that the vessel was TL-12, it had a muzzle velocity of 6,000km/ second. It was capable of firing out 687kg of waste rock in a "firing". ROF was 1 shot per minute, and with a cargo hold of 400dtons, took about 4-6 hours to empty.
Configuring that to a solid shot vehicle/shell..sorry, not my bag. In the New era, some 'rump" navies have been using these MD's against recalcitrant natives on planets they wished to conquer tho..

 

[princelian]

Look to Traveller: 2300....let me think, now....

Nyotekundu Sourcebook describes the OMS Andrew Carnegie, an orbital mining station (that's what the OMS stands for) about 1.6 km long that accelerates ice mined from the rings of the gas giant and sends them toward the hotworld that needs it.

I couldn't find stats in my copy for the power of the accelerator, but it's capable of launching the ice packages for interplanetary distances which take months to years to arrive. And this is TL8.5 or thereabouts, remember.