Considering getting Vehicles 3e for use in 4e games.

[Kalminos]

What should I know?

I've been hit with the allure of fighter-combat based games for a while now, and I make decent use of vehicles on my normal games. Recently, I've been using GURPS Spaceships rules chopped up and made up to run a mecha game.

While that worked out pretty well, I desired more detail- and more rules. spaceships will simply not really do fighter combat. So, I've been thinking for a month or so to buy GURPS Vehicles 3e (since vehicles 4e seems to be vaporware rivaled only by half life 3), but it occurred to me that some rules might get really weird once they're transferred over.

For example, I remember hearing guns in 3e only do blunt damage and piercing doesn't exist. As someone who has never read third edition GURPS, what should I know before I think further on buying?

[Mailanka]

I've been toying with it as well, but I've run into some problems when I use it.

I can see two reasons to build vehicles. Either you're trying to model real vehicles, or you're building hypothetical vehicles. For real vehicles, it's actually pretty easy to come up with stats. I could probably stat up an Abrams for you, if you wanted. You can just study up on wikipedia for the Rolled Homogenous Armor equivalent for DR, and then look at the top speed and acceleration and mass and so on, and pretty soon, you have your vehicle.

For hypothetical vehicles, we have two rough kinds. The first are vehicles-by-fiat. What is the cost of the Death Star? Nobody cares. How much damage does its cannon deal? Enough. What is its DR? Irrelevant, as nothing is going to kill it without doing some crazy quest first. So for these, vehicles is also pointless.

That leaves hypothetical vehicles where we want a consistent and logical system behind them. Pulver once called Vehicles "The technological infrastructure book" and that strikes me as correct. If we decide that our civilization has access to realistic fusion power, what sorts of vehicles does that allow and what sort does that prohibit? Given weapons of this power and nature, what sort of armor would you need to defend against it, and so on.

The problem with this is that GURPS 4e hypothetical technologies are very different from GURPS 3e hypothetical technologies. Ultra-Tech changed considerably between the two editions, and so I find it of limited usefulness to me. On the other hand, Spaceships isn't exactly all that useful to me either. So I find myself adrift, simply waiting for a book that has yet to materialize (and might never be finished)

[Varyon]

Originally Posted by Kalminos

For example, I remember hearing guns in 3e only do blunt damage and piercing doesn't exist. As someone who has never read third edition GURPS, what should I know before I think further on buying?

Vehicles is the only 3e book (well, PDF) I have, and the only one I've ever looked at. I'm quite happy with the way Spaceships handles vehicles, so I've only really read the section on gun design (which was the whole reason I bought the book). Those rules are actually pretty easy to translate over to 4e. First off, while Vehicles does indeed use crushing damage for firearms, High Tech 4e has rules on what caliber sizes fit into each piercing category, so you can just use those - if you design a 10mm Gatling rifle, use the damage Vehicles gives you and just call it Pi+ instead of Cr. Secondly, 3e Acc is about twice that of 4e, so once you've calculated that simply halve it to get an accurate number. Rcl you'll have to estimate based on similar weapons (3e Rcl appears to have been quite different from 4e), and ST in 3e was linear rather than 4e's quadratic progression, so if you want to design handheld weapons you'll want to calculate MinST, subtract 10 from it, take the square root of that, then add 10. For example, a weapon you calculate as having MinST 14 would have MinST 12 in 4e. Another consideration is TL - it's fine up through TL 4, but deviates beyond that. In 3e, TL 5 is 1600-1900 AD, TL 6 is 1900-1950 AD, TL 7 is 1950-2000 AD, and TL 8+ is the future. You can see the breakdown here.

One thing you'll want to look out for is that Vehicles' layout wasn't, in my opinion, up to the standards you'll be used to from 4e. For example, in the chapter on weapon design, it follows a logical progression of starting with mechanical artillery (catapults and the like), then firearms, then launchers, then beam weapons. However, throughout the entire chapter, there is extra information on the side panels that appears to have been crammed in to save space, and while it is indeed part of the chapter, it doesn't really match what's on the page itself. In the mechanical artillery section, you'll find (and I missed until someone pointed it out to me) a discussion on what bore size your firearm will likely need, and what each of the barrel length categories actually correspond to. If you want to design handheld weapons, those rules are in the sidebar in the middle of the beam weapon design rules - and aren't mentioned anywhere else (the constant cross-referencing you see in 4e titles is notably missing in Vehicles).

[Fred Brackin]

Originally Posted by Varyon

First off, while Vehicles does indeed use crushing damage for firearms, High Tech 4e has rules on what caliber sizes fit into each piercing category, so you can just use those - if you design a 10mm Gatling rifle, use the damage Vehicles gives you and just call it Pi+ instead of Cr. ).

3e tended to call _any_ damage without special rules "crushing". It mostly meant that the reduced DR v. Impaling for chain and Kevlar armors didn't apply. The damage modifiers for bullet size existed in 3e too.

[Varyon]

Originally Posted by Fred Brackin

The damage modifiers for bullet size existed in 3e too.

I can find no mention of this in the weapon design rules of Vehicles, and my previous tests indicate that you get accurate damage prior to adjusting for size. For example, the caliver, which is pi++, does 3d+1 cr when designed under Vehicles (and weighs a little more), and 3d+1 pi++ in 4e LT. So, like I said, you can simply use the Vehicles equations and then plug in the pi class based on caliber, and you should get consistent results.

[Fred Brackin]

Originally Posted by Varyon

I can find no mention of this in the weapon design rules of Vehicles, .

Sidebar p.181.

[Kalminos]

My goal isn't to make fiat vehicles- I can do that anyway- I want to actually design them, pretend to be a designer in making them. Finding things wont be too hard since I'm buying them as PDFs, ctrl+F is a powerful thing.

Most concerning thing is the fact that there seems to be quite a range of tech levels as you pointed out- the setting I'd mainly use these rules for is somewhere between tl9 and 13 on 3e's list, but is simply 10^ on 4e.

[Doctor Thantos]

I still use the 3e vehicles for my 4ed game. If you are going to do it, get the Gurps Vehicle Builder. It will make your life so much easier. I had Gurps Vehicle Designer too, which I preferred but isn't really supported anymore. The GVB is similar and does the calcs for you. So much easier...

I like building them with the builder and doing the layouts for ships or building stats for existing 3rd party ships for my campaign.

Skill checks are still skill checks and if you want to change the blunt damage to piercing, go ahead.

I like having an idea of acceleration, speed, etc.

[Not another shrubbery]

Just to point out:
Kromm has mentioned progress on Vehicle Design on his livejournal page recently, so there's hope that we might get that in the foreseeable (if not near) future.

[GodBeastX]

I would just use character sheets for mecha. Am I the only one who feels this way?