BRP Starships pdf - comments welcome

[clarence]

For instance if 1 module is 1 ton, 2 would be 2 tons, but 3 would be 4 tons, 4 would be 8, 5 would be 16 and so on. We could do the same with crew, weapon size and so on.

It looks very neat, but it seems to me you have to look up all those relations in tables (or just one table?). Might not be such a big difference from how it works now, but it seems a bit more direct with 1 module equals 1 person (weapon, ton and so on), and 1 capital module equals 10 people.

Okay, I'm going to write the full length text stuff for my own use and I'll make a short summary version for other people to use as they like.

Sorry Nathan, I didn't mean to cut you short. Write it the way you think will work, and if needed we can discuss the length then.

I've been doing some reading on civilians aeroplanes and ships. Categories currently in use are based on what the ship's purpose is and then there are a variety of systems to rate their sizes (mostly born out of tariff and taxation demands). For the military vessels, I liked Atgxtg's list because it starts with the smallest reasonable manned military craft and then doubles for each category. I think that works great and should also be applied to civilian craft.

I'm going to come up with some examples for different size classes and just include them in the description.

Excellent!

[Atgxtg]

It looks very neat, but it seems to me you have to look up all those relations in tables (or just one table?).

Just one table. All that would change between systems is what you are measuring. For instance, a rating 5 cargo area would be 16 tons, a rating 5 crew area would be 32 people, a rating 5 lab would mean 32 labs, and so on.

Might not be such a big difference from how it works now, but it seems a bit more direct with 1 module equals 1 person (weapon, ton and so on), and 1 capital module equals 10 people.

The advantage with this variant is that you don't need different scales, since it's built into the progression. A capital ship would just have ratings 2-3 points higher than a smaller ship.

One of the neat bits is that while you can determine exactly how many modules a ship takes up with this variant- you don't have to. With a doubling scale you can get a "close enough" estimate just by taking the highest rating and adding 1 or 2.

[Atgxtg]

Would we be better off with a separate list for civilian ships or simply putting civilian examples in the description? For example, under titan, mentioning that the largest colony ships and habitat structures could be that size.

I think the latter. Maybe we could have a SIZ Class for ships, like several other games use, and then just list the various types of ships as benchmark example. For isntance SIZ class 2 could be a fighter, and SIZ Class 9 could be a battleship. Your huge colony ship (SPace Ark?) example could be SIZ Class 10, along with the Titans.

One benefit to that approach would be that it would make it easier for people to adapt the scale to other settings, just by shifting the SIZ class for his ships up or down a point or two.

[clarence]

Just one table. All that would change between systems is what you are measuring. For instance, a rating 5 cargo area would be 16 tons, a rating 5 crew area would be 32 people, a rating 5 lab would mean 32 labs, and so on.

Could you expand the explanation a bit? I designed a few ships with this system, but I'm not sure I got it right. I pick a rating and see how many modules I get? Why does rating 5 equal 16 tons, but 32 people - I thought they would be 16 both of them? It's a quite elegant system, but resolution is a bit low perhaps when doing bigger ships. And for hangar bays the rating-to-module relation will have to be modified, right?

One of the neat bits is that while you can determine exactly how many modules a ship takes up with this variant- you don't have to. With a doubling scale you can get a "close enough" estimate just by taking the highest rating and adding 1 or 2.

I don't understand : )

[Atgxtg]

Could you expand the explanation a bit? I designed a few ships with this system, but I'm not sure I got it right. I pick a rating and see how many modules I get? Why does rating 5 equal 16 tons, but 32 people - I thought they would be 16 both of them?

It should be 16 for each. I messed up.

It's a quite elegant system, but resolution is a bit low perhaps when doing bigger ships. And for hangar bays the rating-to-module relation will have to be modified, right?

Yeah, but that's pretty easy. What you could do is give it a rating and then divde the moduels to get the number of craft.

For instance if a ship had a Hangar rating of 6 it would get a 32 module-sized hangar bay (or a couple of smaller bays). This would allow it to accommodate up to 8 ATV, or 3 small fighters.

Now if we used the rating system for the size of ships then we could just subtract the size rating to get the number of craft held. For instance with a rating 5 hangar bay, and ATVs being size 2 (4 modules each) then we just do 5-2 =3 which would be 8 craft!

I don't understand : )

Because we are dealing with the actual performance, tonnage, people, etc. rather than modules, everything scales up. For instance, let's say we wanted to make a capital ship with a crew of 400 people. With modules we'd need a lot, an might want to use a x5 or x10 scale to keep the numbers down. But with a doubling progression we only need to give the ship a rating in crew quarters high enough to handle 400 people (i.e a rating of 8 can handle up to 512 people).

Likewise if we wanted to build a mile long capital ship with a crew of 40,000 people (i.e. a Star Destroyer), we wouldn't need to make a new scale, we'd just give it a rating of 16 and know that it could handle up to 65,536 people.

In both cases we could assign the crew modules however we liked, for deckplans and such.

Now the fun bit is that when it comes time to work out stuff like speed and handling, we can just use the rating instead of the actual number of modules. So that Star Destroyer would have a a rating of 15 for crew. If it had a rating of say 12 in weapons, 3 in labs, 12 in hangar bays, 13 in engines and so on, we could fit the whole thing in a SIZ Scale 16 hull (1 bigger than the 15, since nothing else came close to the 15). SO we would know the ship was rated up to 131,072 modules- without having to go into the bother of actually counting them and assigning all of them. Note that it could be 100,000 or 120,000 modules, at that size we really don't need to know.

And the reason why we don't need to know is because with so many modules, it would take a lot of modules (I think 10000 if I got the Speed formula right) to change the speed or handling.

So basically, the idea here is that as the ships get bigger this system automatically lets you scale up.

[clarence]

I have designed a bunch of ships now with the different versions of scaling we've discussed here, and these are my findings:

1. It seems to me that a rating with a doubling progression is quite efficient for large ships. Perhaps a bit inaccurate, but I think it works as the design process is so much faster and simpler than counting thousands of modules.

2. For small ships (less than 200 modules approximately) the same rating seems to confuse the design process more than it helps, as the rating for individual systems have no actual use. For a whole ship though, the rating works excellently as a sort of Size Class.

3. I suggest we keep the design system as it is written in the rules now (with the addition of a Size Class stat), and add a sub-heading for designing large ships. Here the doubling progression is presented for individual ship-systems and how that benefits the design process for capital ships.

4. And slightly OT: Working out Speed and Handling is a bit complicated now, as each time you add a new engine module (to up the Thrust Rating), the total number of modules goes up, shoving the calculations for the final Speed/Handling value into constant flux. That makes it a bit unpredictable for players and GMs alike. Would it be ridiculous to just ignore the Engine/Maneuver modules in the calculations and use only the other modules' total for these calculations? (But include them in the total module count that determines Size).

How do you think all of this sounds?

[Atgxtg]

I have designed a bunch of ships now with the different versions of scaling we've discussed here, and these are my findings:

1. It seems to me that a rating with a doubling progression is quite efficient for large ships. Perhaps a bit inaccurate, but I think it works as the design process is so much faster and simpler than counting thousands of modules.

Exactly.

2. For small ships (less than 200 modules approximately) the same rating seems to confuse the design process more than it helps, as the rating for individual systems have no actual use. For a whole ship though, the rating works excellently as a sort of Size Class.

Yeah, that's because we think in linear terms, not exponential ones.

One other little perk that I didn't mention is that since the BRP SIZ table also uses a doubling progression in the SIZ8-88 range, it is easy to convert from a rating to a SIZ or STR stat.

3. I suggest we keep the design system as it is written in the rules now (with the addition of a Size Class stat), and add a sub-heading for designing large ships. Here the doubling progression is presented for individual ship-systems and how that benefits the design process for capital ships.

Hey, they are you rules. I'm just tossing out ideas for handling some hurdles.

4. And slightly OT: Working out Speed and Handling is a bit complicated now, as each time you add a new engine module (to up the Thrust Rating), the total number of modules goes up, shoving the calculations for the final Speed/Handling value into constant flux. That makes it a bit unpredictable for players and GMs alike. Would it be ridiculous to just ignore the Engine/Maneuver modules in the calculations and use only the other modules' total for these calculations? (But include them in the total module count that determines Size).

Yup. Oh, and BTW, congrats, that's actually one of the problems that go with rocket science in the real world. You add something new to a rocket, and it ups the mass a couple of kilograms, so you need a couple of kilograms more thrust, so you need to tweak the engines, but now you have to add more fuel, so that adds more mass, and so on.

The "solution" to that problem is to pick the size of the ship first then fill in the spaces with components. That way the final size (and mass) never changes, so you don't have to constantly recalculate every time you add another module.

Also, since Speed and handling are on a 1-20 scale, it's easier and more efficient to add engines in increments of 5%.

How do you think all of this sounds?

Sounds okay, except I think it would be better if we have one system for design, not one for small ships and one for large ships. Maybe we can trim off the stuff from the rating system that is most helpful and important, such as a total size, and size class.

What if we started the design process by picking a size class and number of modules and then filled it in with components? That way we get the ability to work with large increments or by individual modules as needed.

Edited May 22, 2014 by Atgxtg

[clarence]

Sounds okay, except I think it would be better if we have one system for design, not one for small ships and one for large ships. Maybe we can trim off the stuff from the rating system that is most helpful and important, such as a total size, and size class.

Well, it's almost one system. The only difference is that it is meaningful to use a size rating for a part of a ship when doing big ships. All else could be equal I think?

One other little perk that I didn't mention is that since the BRP SIZ table also uses a doubling progression in the SIZ8-88 range, it is easy to convert from a rating to a SIZ or STR stat.

Sounds good. What does the conversion look like?

Oh, and BTW, congrats, that's actually one of the problems that go with rocket science in the real world.

I'm happy I'm not a rocket scientist : )

The "solution" to that problem is to pick the size of the ship first then fill in the spaces with components. That way the final size (and mass) never changes, so you don't have to constantly recalculate every time you add another module.

Ah, that was one of the things I wanted to stay away from when I started this. Too many ship design rules begin with the question of hull size - but I always wonder how I can know that. It seems more intuitive to just keep adding functions you need and see what hull size you end up with. I realized though that engines will take up approximately 10-20% (Speed 10 and upwards) of the number of modules, so that's probably simple enough for me.

Edited May 23, 2014 by clarence

[Atgxtg]

Sounds good. What does the conversion look like?

Since each doubling is +8 on the SIZ table from 8=88 then if one module is, say, two tons (SIZ 50), then each time you double the number of modules you add 8 to the SIZ. It holds true up to about 16 modules (SIZ 90). At that point the SIZ progression in BRP is all over the place.

I'm happy I'm not a rocket scientist : )

That's why there is a common expression, "It's not rocket science", that gets used a lot when dealing with something that ins't very complicated. Rocket science gets complicated because there aren't many constants.

Ah, that was one of the things I wanted to stay away from when I started this. Too many ship design rules begin with the question of hull size -

There are very good reasons why most rules start with hull size. Some many other factors are dependent on it. For example, we've already hit on the problem with needing more engines as you increwase the mass just to keep the same speed. But the same holds true for power systems, life support and so on.

but I always wonder how I can know that.

Because form follows function. If you know what the ship is supposed to do, then you should have an idea of what it needs to do it, and how big it should be. In the real world most engineers start by making some basic assumptions about a vehicle, such as mass and desired speed, and then fill in the gaps. Then they usally adjust the mass and other starting assumptions as they modify the design.

For instance, with real world fighter jets, engineers can assume that about 15-50% of the plane weight will be taken up by the engines, and another 35-40% taken up by frame and structural support (so it can take the stresses associated with hight speed and high G turns). So 50-90%, or, on average about 2/3rds of the fighter's total weight is already spoken for before the designers get to the drawing board.

The same concepts hold true for other vehicles. A battleship, for instance, is built around big power guns, and most everything else, such as armor, ammo magazines (ammo weight adds up quickly when you're firing two ton shells!), number of crew, accomodations, food stores, so much of it is dependent of the guns.

It seems more intuitive to just keep adding functions you need and see what hull size you end up with. I realized though that engines will take up approximately 10-20% (Speed 10 and upwards) of the number of modules, so that's probably simple enough for me.

If you want to take that approach then I suggest a table with Speed and handling as a percentage of the total modules. It will make it much easier. I think it works out as 1 SPEED = 1% of modules, but I'd have to check.

[clarence]

If you want to take that approach then I suggest a table with Speed and handling as a percentage of the total modules. It will make it much easier. I think it works out as 1 SPEED = 1% of modules, but I'd have to check.

Yes, I've thought about that too. Just as a quick and dirty way of knowing approximate values, and then you can adjust from that point without too much fuss.

Because form follows function. If you know what the ship is supposed to do, then you should have an idea of what it needs to do it, and how big it should be. In the real world most engineers start by making some basic assumptions about a vehicle, such as mass and desired speed, and then fill in the gaps. Then they usally adjust the mass and other starting assumptions as they modify the design.

For instance, with real world fighter jets, engineers can assume that about 15-50% of the plane weight will be taken up by the engines, and another 35-40% taken up by frame and structural support (so it can take the stresses associated with hight speed and high G turns). So 50-90%, or, on average about 2/3rds of the fighter's total weight is already spoken for before the designers get to the drawing board.

Experience with the design process is the key here I think. And many players will only design one ship, or at least design ships very irregularly.

[Atgxtg]

Yes, I've thought about that too. Just as a quick and dirty way of knowing approximate values, and then you can adjust from that point without too much fuss.

It's not approximate. If I got your math right, then a 100 module ship with 10 standard engines moves at speed 10 (1000 thrust divided by 100 modules). So the 1 SPEED = 1% of total modules is exact.

I was working on a percentage based design system a few years back. I found it good to work with, but most everyone else I showed it to seemed to hate it.

BTW, the 10:1 thrust ration of your engines is the sam value I used! It's also just about right for a modern jet engine.

Experience with the design process is the key here I think. And many players will only design one ship, or at least design ships very irregularly.

Yeah. I figure most GM will design a half dozen or so. A PC ship, a bigger firednly ship, a shuttle, a fighter, and some bad guy ships. It would probably be good to come up with some guidelines to make it easier on them.

[clarence]

1 SPEED = 1% of total modules

Great, this will be added to the rules!

I have also started to make room for the combat rules additions in a separate chapter called Advenced Combat. So far, the sub-headings are Weapon Options, Damage, Armor, Fire Arcs, Ammo, Hit Locations. Does that cover most of it? Anything else needed? I have a spread free for it so far, but if needed, adding more spreads is easy.

The Size Rating Table is now residing right after the description of Modules, including the way to use them with all ship sizes, and how to utilize them to ease the design of large ships.

The example sizes of military ships is also included now.

[Atgxtg]

Great, this will be added to the rules!

1% values for the other drives are as follows:

Cutting Edge 1.2 speed per 1%

"Standard" 0.7 speed per 1%

Economy 0.4 speed per 1%

I have also started to make room for the combat rules additions in a separate chapter called Advenced Combat. So far, the sub-headings are Weapon Options, Damage, Armor, Fire Arcs, Ammo, Hit Locations. Does that cover most of it? Anything else needed? I have a spread free for it so far, but if needed, adding more spreads is easy.

Sounds about right so far.

One thing you might want to add is some sort of guideline for crew. As it currently standard, there is no reason a Dreadnought can't be crewed by two people. Perhaps some function of the number of modules?

Edited May 26, 2014 by Atgxtg

[clarence]

Cutting Edge 1.2 speed per 1%

"Standard" 0.7 speed per 1%

Economy 0.4 speed per 1%

Perfect!

One thing you might want to add is some sort of guideline for crew. As it currently standard, there is no reason a Dreadnought can't be crewed by two people. Perhaps some function of the number of modules?

Oh yes, naturally. I will try to come up with something (unless you have a suggestion?).

[Atgxtg]

Oh yes, naturally. I will try to come up with something (unless you have a suggestion?).

I'd suggesting typing the crew requirements to the size class. It depends on how many crew you want, but for starters how about something like this:

titan (160-480)

battleship (80-240)

cruiser (40-120)

destroyer (20-60)

frigate (10-30)

corvette (5-15)

cutter (3-8)

small craft [2-4]

fighter (1-2)

How does that look? I think you might have a problem with ships being all crew space through.

Perhaps some sort of sliding scale for accommodations?

the 4 modules per person could be for nice, passenger accommodations, say 2nd class.

The whole scale could look like:

Luxury Accommodations: 16 modules per person (five star first class accommodations on ma passenger liner; for the ultra rich)

1st class civilian: 8 modules per person

2nd class civilian: 4 modules per person (standard)

3rd class civilian ("coach"/"steerage"): 2 modules per person

Military, Officers Quarters: 1 module per person (a bunk with some storage space)

Military: 2 people per module (a pair of bunk beds)

-Hot bunking could reduce the crew requires up to half again.

That way, if you have a 400 module cruiser with a crew of 100, you could fit 10 officers in 25 modules or so, and 90 crew in 45 modules (30 or even 23 with hit bunking) and still have 30 modules to actually build a ship with.

You might want to add an automation feature that drops the crew requirements down a step or two on the ladder per module.

Edited May 26, 2014 by Atgxtg

[clarence]

Yes, that looks about right! And a civilian crew could be somewhere between 4 (standard) and 1 (crammed).

What is also quite interesting, is the minimum number of people needed to run a ship. I would say that one person is enough to run a ship (including one weapon) up to about 100 modules in heroic sci-fi. After that maybe 10% of the crew is the minimum.

You might want to add an automation feature that drops the crew requirements down a step or two on the ladder per module.

That's a good idea, and can also be used to simulate high-tech cultures.

[Atgxtg]

What is also quite interesting, is the minimum number of people needed to run a ship. I would say that one person is enough to run a ship (including one weapon) up to about 100 modules in heroic sci-fi. After that maybe 10% of the crew is the minimum.

Run it maybe. Probably not maintain it though. In real life there are reasons why crews are the size the are. For instance, you want to have enough people on a military ship to run it at all times. You don't want to lose a ship because it was the crew's nap time.

That's a good idea, and can also be used to simulate high-tech cultures.

Yup In fact I could see Tech Levle adding into the rating of some systems. I suspect a 2 ton TL 15 particle cannon is probably better than a TL 13 one.

[clarence]

Run it maybe. Probably not maintain it though.

Yes, only for a short period of time.

In fact I could see Tech Levle adding into the rating of some systems.

Added: Either takes up more space or is less efficient with low tech levels, and the opposite for high tech levels.

The chapter for Advanced Combat is taking shape, and I've copied/pasted quite freely from our discussion here. Two spreads at the moment. No hit locations so far - I think NathanIW might be at work with that.

[Claybor]

This looks pretty darn good and not too complicated or involved. Thanks for sharing.

[clarence]

You're welcome! It's been a pleasure putting it together. I'm happy you like it and I hope you will find some use for it.

[clarence]

I have just finished BRP Starships version 2.0 and added it to the download section (sci-fi folder).

What's new:

- Beautiful cover art by Jadrien Cousens!

- Advanced Combat chapter, courtesy of Atgxtg. Includes weapon up- & downgrades, damage ladder, differentiated armor & fire arcs.

- Scale is now x10 and called Starship Scale. Previous Small Scale renamed Planetside Scale.

- Constructs chapter by Frank Mitchell. Details on robots and their uses.

- Easier system for designing capital ships, concept by Atgxtg. Size Rating value introduced.

- A short list of personal weapons, armor and equipment. Equipment write-ups by kind permission of Jason Durall.

- Table of contents.

If you enjoy the cover art, please visit Jadrien Cousens' webpages to show your appreciation:

www.jadriencousensart.com or www.jadrienc.deviantart.com

I'm still interested in how the rules work in everyday play. All comments are welcome.

[clarence]

With BRP Starships 2.0 finished, my plan is to continue work on the rules for alien creation and perhaps some additions to BGB psionics. I started reading Mindjammer RPG and found it to be the most inspiring alien creation I've encountered in a long time, so my original notes are being restructured a bit at the moment...

[clarence]

I just saw in Downloads that there are multiple headings for BRP Starships 2.0. Anyone know why or how they are related to the actual files?

[Atgxtg]

Looks like some sort of glitch - probably related to the recent change in the forums Triff instigated a few weeks back. The various files all seem to be the same exact file uploaded and updated at the same exact time. Someone should probably drop Triff a line and let him know.

[clarence]

That's what I thought too. How do I send Triff a message in this new system anyway? I tried yesterday, but the only response I got was that he can't receive messages. I'm sure I miss something obvious.