Ship Design Philosophy

Discuss the Traveller RPG and its many settings
h1ro
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Re: Ship Design Philosophy

Postby h1ro » Wed Apr 12, 2017 6:53 pm

Condotierre et al

What's the smallest ship you can effectively mount the three different bay sizes to?

(Thought this was a good question for this thread, I can repost in the forum if you prefer)
Condottiere
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Re: Ship Design Philosophy

Postby Condottiere » Wed Apr 12, 2017 10:15 pm

Depends.

If you're happy with three fifty tonne ones, that would be a three hundred tonner, though technically it would be a boat, since I'll assume you would want a decent real space performance and armour.

Technical level would dictate how much juice you can squeeze out of the engines to power the spacecraft and it's weapon systems, and missile and torpedo variants tend to substitute space saved on power plants with magazines containing reloads.

Three bays would optimize your design towards an attack ship, and will probably need escorts.
h1ro
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Re: Ship Design Philosophy

Postby h1ro » Wed Apr 12, 2017 10:32 pm

Would you say bays follow the rule in 2e that no spinal can be more than 50% of the ship's tonnage? And that 3 bays of either size would work as a good starting point?

I've written a spread sheet for ships in 2e. It's bigger than I want it to be so I'm looking at breaking it down into a few different size ranges. I've normally been a small ships universe kinda guy but with the same sequence for all, it's pretty easy to do ships from 500dT to 10s of thousands. I don't see myself going bigger than that for warships, bulk container ships maybe but I don't need to worry about bays and spinal mounts for civvie ships.

I've very little experience with ships this size so I'm looking for general ideas on what works at what size.
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Re: Ship Design Philosophy

Postby AndrewW » Wed Apr 12, 2017 11:48 pm

h1ro wrote:
Wed Apr 12, 2017 10:32 pm
Would you say bays follow the rule in 2e that no spinal can be more than 50% of the ship's tonnage? And that 3 bays of either size would work as a good starting point?
Nope, that rule only applies to spinal mounts. For the earlier edition there are some <100 ton craft with a 50 ton bay.
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Re: Ship Design Philosophy

Postby AnotherDilbert » Thu Apr 13, 2017 12:10 am

h1ro wrote: What's the smallest ship you can effectively mount the three different bay sizes to?
You can squeeze in a medium missile bay reduced to 70 dT into a 100 dT hull.

You can squeeze in a large missile bay reduced to 350 dT into a 400 dT hull, but you need 5 hardpoints, so 500 dT hull.

An effective ship would be far larger, of course...
h1ro
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Re: Ship Design Philosophy

Postby h1ro » Thu Apr 13, 2017 7:37 pm

OK, I don't think I phrased my question well.

At what size do ships using small, medium and large bays become effective?

Are you guys designing ships to stand alone or as part of a fleet?

Arming a ship with a spinal mount is great till it comes up against a sub 2000 ton ship it can't hit. Now, I don't like that rule but that's a topic for another thread.

Are you designing ships with a spread of turrets, bays and spinal mounts?

Is there a trend in that spread? My earlier question about bays and 50% of tonnage was about this - I know the only limit on bays is hard points, but typically, what tonnage is being committed to weaponry?

Basically, how do you min/max the rules to get the best ships?
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Re: Ship Design Philosophy

Postby Condottiere » Thu Apr 13, 2017 9:41 pm

Bays are built into the hull, hulls are built around spinal mounts.

I'm going to speculate that current combat rules are in a transitional state.

Bays need hardpoints, and smallcraft only have firmpoints; put a torpedo bay onto a hundred tonner, and you get a torpedo boat, a barbette would make a smallcraft a torpedo bomber.

Warship design tends to be a series of compromises, and those depend on prevailing naval doctrines at the time of design, construction and life extensions. The doctrines depend on the perception of threats and the best way to counter them, or project power.
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Re: Ship Design Philosophy

Postby h1ro » Thu Apr 13, 2017 9:56 pm

Yeah, I knew it was too broad a question...

At the moment this is what i'm working to:

small <100 tons, firm points
medium 100-1000 tons turrets and barbettes
large 1000-5000 adds bays
extra large >5000 adds spinal mounts

There's more to it than that and I'm really not sure it's a good spend of time but there's one way to find out!
h1ro
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Re: Ship Design Philosophy

Postby h1ro » Thu Apr 13, 2017 10:01 pm

Condottiere wrote:
Thu Apr 13, 2017 9:41 pm
I'm going to speculate that current combat rules are in a transitional state.
What makes you say this?
Condottiere
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Re: Ship Design Philosophy

Postby Condottiere » Sat Apr 15, 2017 12:08 am

Feels very betaish.
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Re: Ship Design Philosophy

Postby Condottiere » Sat Apr 15, 2017 11:41 pm

Spaceships: Floating Cities and Orbital Range Gravitational Drives

Image

Anyone know the volume of a city?

Because ORANGRAVIDs (Orbital Range Gravitational Drives) would be perfect as the lifting medium.
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Re: Ship Design Philosophy

Postby Condottiere » Mon Apr 17, 2017 2:21 am

Spaceships: Engineering and Solar Panelling

Solar panels are very much connected in terms of output and technology level to a specific power plant type, with the added bonus that the production cost remains fixed, regardless.

A fully functioning solar panel that is fully bonded to a specific power plant takes over three quarters of the output, which at technological level fifteen would be one hundred fifty scotts per tonne.

These caveats about minimal manoeuvring and non firing of weapon systems are downright vague, and mean nothing, especially if you can circumvent them by storing the energy first in a battery, which can the distribute it apparently more efficiently to the ship's basic systems, sensors, manoeuvre drive and weapons.

I\ll buy the fact that extended solar panel arrays might be too fragile for a constant acceleration greater than one gee, or over an extended period of time, but that has to be explained in the text, and can be circumvented by embedding the solar cells directly on the hull, which would make it a requirement to tack like a sailing ship, to optimize the angle from a light source.

One glaring oversight appears to be when we take that no power plant option: how will we figure out the output per tonne, unless the book assumes we default to a declared technology level of a virtual power plant, made at the time of the installation of the solar panelling?

Even then, it's supposed to be sufficient for basics plus factor one manoeuvring, which is three scotts per ten tonne volume of hull. If you do that for a thousand tonner, that would be a fifteen tonne technological level fifteen fusion reactor, or a one point five area of solar panelling, which would be oddly even more efficient since it would produce the full two hundred scotts of power output, instead of the twenty five percent compromised one hundred fifty scotts that I calculated solar cells would produce to their actual bonded power plant.
Last edited by Condottiere on Tue Apr 18, 2017 8:25 pm, edited 1 time in total.
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Re: Ship Design Philosophy

Postby Condottiere » Mon Apr 17, 2017 10:48 pm

Spaceships: Terminology

_/Raft - whitevan, or maybe a pickup or flatbed truck, with at least limited range manoeuvre drives
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Re: Ship Design Philosophy

Postby Condottiere » Tue Apr 18, 2017 8:50 pm

Spaceships: Engineering and Solar Panelling

Some things that have to be cleared up are the definitions of full thrust, minimal manoeuvring, and long periods

You would naturally assume that full thrust is related to mentioned factor one constant thrust, as opposed to a possible factor nine gee constant possible at technological level thirteen, or even higher accelerations.

How many turns or hours would be a long period? Is there a cool down period, after which you can use the thrusters for another long burn? Could you just use the manoeuvre drive in a series of short bursts that would equal to the long period?

Why not have another virtual power plant that a second set of solar cells are bonded to, and use the energy derived from there to power the sensors and weapons systems?
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Re: Ship Design Philosophy

Postby Condottiere » Mon Apr 24, 2017 9:20 pm

Spaceships: Inspiration

https://www.youtube.com/watch?v=f2wT-FKskXo

Looks like smallship combat.
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Re: Ship Design Philosophy

Postby Condottiere » Wed Apr 26, 2017 6:32 pm

Spaceships: Engineering and Classic Legacies

And speaking of legacies.

One issue that always annoyed me was the artificial separation for engineering between smallcraft and smallships.

It was obvious that you could install the smallship alphabet soup drives into smallcraft, which is where you get the performance parameters of the modular cutter and the ship's boat.

I don't see the commercial case for a factor four driven modular cutter, or practically any other commercial or private ship, since manoevre factor three is obtainable at technological level ten, and is optimized at technological level thirteen.

In a normal atmosphere, you can't really go faster than hypersonic, and only a military craft would want or need to.
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Re: Ship Design Philosophy

Postby Condottiere » Fri Apr 28, 2017 7:40 pm

Spaceships: Large Smallcraft and Cockpits

Can you install? The rules don't explicitly exclude them.

A one and a half tonne cockpit is equivalent to a three tonne bridge, without the legroom and extensive life support equipment.

There are no penalties for operating a spacecraft upto fifty tonnes in volume, by substituting a cockpit for a three tonne bridge.

Therefore, if a cockpit is a three tonne bridge equivalent, it should be able to operate a large smalllcraft, though with an imposed minus one dice modifier for all checks related to spacecraft operations performed from the cockpit.

The cost would remain at ten kay schmuckers.
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Re: Ship Design Philosophy

Postby Condottiere » Mon May 01, 2017 11:14 am

Spaceships: Hull

Image

And lots of aluminium, with steel connectors.
h1ro
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Re: Ship Design Philosophy

Postby h1ro » Mon May 01, 2017 2:53 pm

Very 1970s...

Roll on the materials tech revolution!
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Re: Ship Design Philosophy

Postby Condottiere » Tue May 02, 2017 12:21 pm

It's really more of an issue of sandwiching a material or layer that prevents heat or cold from penetrating from the outside environment inside, since metal tends to act as a conductor.

Or if it's sandwiched, preventing the outer and inner metal hull components from touching each other.

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