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Alternate design technologies

apoc527

SOC-12
Ok, so here's a question for you to ponder-

T20 is "supposed" to be a generic set of rules for sci-fi games. What if I want to create ships and stuff that use different technologies for sub-light and FTL travel? I'd explain more, but you get the point, and I have to leave.

Thanks!
 
well that depends. If the *numbers* in the book work for you, please call the drives whatever you like, and have them work however you want.

If the number don't work for what you want, then simply (yes, it is that easy) designate a new type of drive, with tonnage, cost and performance, and go from there.

Expect the side-effects of such new systems to take a while to manifest themselves in the rest of the design system. A lot of the time, you won't see those side effects until you've actually designed a ship or three...
 
I wanted the drives requirement to scale up as the ship size increased.

So I slapped another chart on the side which just increased the number of drive units required.

I didn't want jump fuel so none is required.

My Jump drive puts the ship into a strange space - where their man drive can drive them at a significant multiple of Light speed. So a Low Jump drive ship with a big man drive travels faster in jump than a low Jump Low Man Drive (M*J*J parecs per week)

I wanted more "power" fuel so limited the Fusion plant to TL11 - Needing to power Man and Jump at the same time put this as significant.

I wanted a bigger difference between Mil ships and civy ships - with the option of up-gunning civy ships a fair bit (but never into the same league) so I allow 1 mounting per 100 tons with a "large" mounting per 200 tons, a larger mount per 500 tons etc. The End result was that a 500dT ship can have 1 big mount, 2 medium mounts and 2 little mounts. The size of the mounting is determined at design time and can't be changed later. But civy ships only mount 1 weapon per mount (and only bother with light mounts) - so an upgraded civy would end up with 5 triple light turrets - can easy take another civy.

SO my answer is - what ever results you want, it is easy to change the design process to match your universe (as it has been with all the other design processes)

If you want a hand, tell us what assumptions need to be supported and we'll give you some rules.

Aside 500dT is the "right" size for Merchies with my rules - they are more economic than bigger ships. The computer savings make Mil ships bigger. Quick mil ships are small (so there is the lumbering Battleship surrounded by a cloud of escorts - which is what I wanted)
 
Still playing with the rules.

They are currently to "agressive" ship combat tends to go to whoever fires first - I need to improve the defenses - tempted to give every ship 3pts armour for free however still up in the air.

Also the "penalty" for the engines is too large - at 10kdT warships consist of Man1 J1 plus guns and it can;t fire all of it's gunbs whilst accelerating! So I need to reduce the penalties.

So far, the journey is the destination however I am closer to "write ups" than I expected and my 3D mapping program is going better than expected.

We shall see how much I get done over the weekend.
 
Thanks guys, that's good advice. Like I said, I have very little experience actually USING design rules, so I'd like my first time to go smoothly. I'll probably try and break my teeth on some standard T20 designs, and then work with some new stuff. I didn't have any concrete ideas, but here's a few random things-

1. Lower tech maneuver drives: let's say I want a rocket based (or other reaction drive) that requires fuel and can regulate the speed based on the speed of the burn. Actually, don't even bother, as I'm never going to play a game with reaction drives. My next idea though...

2. I'm not sure how many of you are familiar with David Weber (I suspect more than a few), but how about his Honorverse impeller drives? You know, the ones that have accelerations in the 100's of g's. (The more modern warships accel at like 550 g's). Slightly different is the Starfire universe which uses a drive field that is inertialess (power to field = movement, no power = dead stop). Those ships can get up to significant fractions of c (but fortunately the "near-c bombardment option" doesn't exist, since their drives must have constant power applied, it just wouldn't be practical, unlike in the Honorverse).

3. Star Trek style warp engines or Star Wars style hyperdrive. There's also the David Weber "sailing through hyperspace" variant and the straight, effectively non-FTL "warp point" system of Starfire. I guess most of the other sci-fi FTL systems are a variant on one of these primary types.

4. Weapons are significantly easier, and with the examples already present, I'm confident I could successfully BS any random weapon technologies that I like. Most of the ones I'd ever use are already there. I might apply my "natural Armor Piercing" idea to shipboard weapons too, but then I'd also be inclined to give ships 1-3 points of "free armor" (GURPS gives a minimum of DR100 to all ships, to protect against micrometeorites and the like).

I guess that's all for now. Also, Mink, when you're done with your stuff, I'd love to see it.
 
APoc527:

See if you can get your hands on a copy of FF&S-GDW from the tne era..It has a listing of alternate technologies. Some maybe useful some not..Or adapt from these other games.
A heretical suggestion only...
 
For David Weber/Honor Harrington a couple of initial mior changes:

Rather than displacement tons, the ships are measured with mass tons.

All mil ships are Needles. All civilian ships are Close Structure (the relative price difference is important). No ship ever lands and practically all carry small craft which are identical to Trav small craft.

They have frieghters at about 5 MdT with crews of 30ish people - so a conversion of about 10mass tons per dT seems reasonable.

The Drives themselves are a little trickier.

First off, he doesn;t really understand what a G is. He has a person in a vaccsuit with a reaction thruster get propelled at an erratic 35G for a couple of minutes. They get whiplash and mortion sickness bad enough to throw up - breathing in vomit and burning their lungs. 35G means you can;t breath, your fleash schreds from your bones and you get very dead - if it's erratic then you probably get bones snap as well. With that in mind there are a couple of proviso's

The Acceleration is internally "compensated" so the actual number only matters for seppeds arround the system. If you use vector ship combat and just jump all the Accell numbers by a factor of 100ish you will get to the right ballpark.

Write two sets of man drive units - the first is pretty much the same as current and is his "commercial" drives. The second is mil drives - costs three times as much and has roughly twice the Accell (ie a military 2G drive unit costs 5.25MCr and the ship generates 400G)

There is a drive "limit" that is constantly creeping up based on tech level. This limit is based on ship size and I would start with a table (you can build one up by reading up on the accells that he gives his ships)

Mil drives can operate at 1/3 their max accell with no problems, upto 2/3 accell fairly reliably and upto max accell by puttin gmore "wear" miles on the drives.

Jump drive is pretty much covered in the books - there is no Jump fuel.

Ships carry more rations (otherwise you won't have anything to spend that space on) and this is what limits endurance rather than fuel. There is effectively no fuel for powerplants.

At least the above gives an "approximately" harrington esk ship building rules (based on t20)
 
Originally posted by Liam Devlin:
APoc527:

See if you can get your hands on a copy of FF&S-GDW from the tne era..It has a listing of alternate technologies. Some maybe useful some not..Or adapt from these other games.
A heretical suggestion only...
I've been reading thru those rules in my copy Liam. Can someone explain the speeds of the Subspace drive? Maybe I'm just to dense, but I can't figure out how many parsecs per day/week/etc the drive is capable of. The formula doesn't make sense to me :confused:
 
I have created rocket rules -- did it back right after MT came out (before FF&S). I have copy of FF&S but to be honest I never really messed with it much, preferring instead to use the houserules CT/MT combo that I did.

I played in a trav game once where the GM had the Jump number being the number of Parsecs traveller per day -- and there was no entering jump space. It was more like a warp-drive kind of thing. It changed the game a LOT. Made it more star-trek like IMO.

One of the early CT house-rules we came up with back in the day (old-timer voice) was to do away with fuel and use 'fuel-rods' instead. These were radioactive fuel rods and were used to generate power by the drives. This meant that the gigantic fuel requirements weren't needed, just a 'radioactive storage' box and your ship was powered for X months before you needed to change our your fuel rods.

The rules are so modular that you can plug and play almost any variant you want, and make it quite easy.
 
Just a few thoughts.. sorry about the disorganization.

I was looking for some way to change the dynamics of space travel.. and discovered that removing G-compensation from the equation works splendidly. Sure, it increases travel time in system, but that was a price I was willing to pay.

Rather than tooling around at 3+ G, most ships maintain a nice, steady 1G of acceleration.. until the fur starts to fly. Now, G-loading becomes a critical factor. How much can you take? For how long? G-suits and "G-couches" have become the word of the day.

In addition, I've also made ships stand out against the background of space. You know that someone is out there. You might not initially know who, but you know where.

Finally, I too have differentiated between mil and civ craft. Warships are incredibly expensive, and built using a higher level of tech. They also tend to be a bit more fragile. They require a ton of preventative maintenance. Civ ships, in contrast, tend to be slower, cheaper, and less heavily armed and armored (considerably so). They trade performance for reliability.
 
Ellros:
The formulae is V=(MW divided by Displacement) x Efficiency.

So...a 435 MW driven T-class patrol cruiser divided by (400dtns)
comes to 1.080705 x TL-15 eff(.9) =(.9726345)

the velocity of ship, in this case by the .01 parsec scale to .097 parsecs a thirty minute game turn in Brilliant lances. (Actual number should be rounded up)or .1 parsecs meaning in five T-hrs (10 turns), this sublight drive can cross a parsec. Of course-it eats fuel the whole way there, and the ship has to have a seperate drive for it.

435MW drive x TL modifier of.10 =43.5cubic meters or 3.6 displacement tons at this TL. Lower tech Sublight drives will be larger..

Our example the T-class Patrol cruiser has a onboard docking bay for a 30dtn ships boat, and 15dton missile magazine. One could say the sub light drive fits into the docking bays space, and make do with a 20dtn fast pinnace.

Any questions?
Utilizing pp45 & 46 FF&S.
 
Now Apoc527:

If'n ye want to use these, and have no FF & S handy...
TL Vol. Eff
TL-9 .50 .60
TL-10 .40 .65
TL-11 .30 .70
TL-12 .25 .75
TL-13 .20 .80
TL-14 .15 .85
TL-15 .10 .90** our example
TL-16 .08 .95
TL-18 .06 1.00
TL-20 .04 1.10

fer yer use, of course...
 
Subspace is akin to J-space, yet is a fluid form, as the book describes. Maintaining Subspace at a hover ("on station") requires power as well.
How much power?
Mass/ cubic meters or in my above example 3.6 x efficiency modifier (.9)= or 3.24MW. Leaves lots of energy to run everything else...

But...

Missiles and sandcasters are useless unless they too are equipped with subspace drives (impractical & expensive); Lasers, N-PAWS, and meson guns are unaffected however!
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How much fuel is consumed? What kind of fuel is used? Those are decisions you as a GM must make. :D
 
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