Spaceships for modern TL7/8 aquadic naval veseel

[fdsa1234567890]

Looking at the rules given in Pyramid 3/34 in terms of adapting them to create modern naval vessels I see two fundamental problems. While fine for the basic issues of adapting things like habitats and general layout, there are two fundamental problems: Missiles/guns and radar.

The fundamental problem is that the missiles and guns listed are obviously intended for space combat and adapting them to fit a modern context won't really work. I supposed I could make up my own stats for modern missiles, but that would be outside the system shown.

Using the example listed in 3/34, it shows 28 cm missiles carried by a warship with dDR 7 and dHP 150. Those would do on average ~140 points of (d)damage each shot(6dx7). While that is somewhat realistic, given that the USS Stark and HMS Sheffield nearly died and actually died to a single missile hit each, for a larger cruiser it seems off.

The second fundamental problem is radar. Radar sets in Spaceships(for tactical arrays) have a range of between 200,000 and 600,000 miles when adapted for a realistically sized warship. That is obviously absurd. In this case I suppose I would have to simply make up my own system, likely based on that of 3e Vehicles. Though of course using radar on Earth, the fundamental limitation is that of the radar horizon, one of the largest reasons that aircraft carriers are the key to modern naval warfare.

Also as a more general question about Spaceships, are there equipment modifiers for lower quality systems?

[weby]

Current naval warships are really not able to resist any damage. The armored warship went out with WW2 basically. So on that part it is not unrealistic at all. The same goes for larger warships. The newest warships have again a bit more armor, but it is partial coverage only protecting most vulnerable parts.

The base problem though is that gurps handles the damage to large objects really badly at base. The cube root of object weight really makes destroying large things way too easy with light weapons.

As example of a large modern carrier. The base armor it has is really low compared to the damage dished out by any heavy weapon. Basically any antitank missile size weapon should be able to shoot holes in it. But it consists of thousands of water tight compartments and has good bilge pumps. So in real life being hit by even few hundred such weapons would likely hurt it a lot and might start some fires and similar secondary effects that might indeed destroy it, but the raw damage would just punch a lot of holes in the outer hull and it would still keep floating. But in gurps the extra damage that goes through the armor would just destroy it in short order(as in go over -10 times hitpoints).

I have personally started scaling things to the square root of weight in my games and the results work much better. It simulates the work needed to create equivalent relative hole in targets.

The other issues:
The radar: The ranges given for radar are space ship ranges, for terrestial radars you have several issues that you do not have in space. The major issue being that in space any return is likely worth investigating further, but on earth you have everything from flocks of birds down to tornadoes returning false positives. 3e treated atmosphere as 1/10 range if I remember correctly, but even that likely underestimates the difference. But overall larger current military radar systems can indeed detect non stealthy targets out to the local horizon so range does not really matter.

No, there are no special modifiers in spaceships for different quality equipment, though I guess you could use the generic gurps modifiers.

Overall, the adaptation of Spacehips system for other vehicles is a very broad level thing. and really even for building space ships it is the same thing. It is good for building things under a given set of expectations, but given overall broken nature of damage on large targets and such it cannot model a lot of scifi settings (and even so realistic things seem iffy)

So building your current naval ships, I would recommend just basically ignore the space ships system and use the real world values or extrapolate from such values. And if you intend to use them for actual fighting give them a LOT more hitpoints that given by gurps.

[Varyon]

If you have Vehicles 3e, I suggest building the weapons there. You may want to reverse-build some of the already available options to get an idea of how Range, Acc, cost, and so forth changed between editions. If you already know what TL you'll be working at, and what sort of weapons you're designing, you can simplify the design process quite a bit - I adjusted (and simplified) it for ~TL4 and ended up with every weapon having only three variables (Caliber, Length, Power) to work with, with no need for table look-ups (I allowed for arbitrary length and power, rather than having specific cut-offs, although I limited length to no more than 50 calibers and power to no more than 100%). I had the rest of the options - pistol vs longarm vs cannon, muzzleloader vs breechloader vs revolver, smoothbore vs rifled, etc - as simple add-ons. If you're expecting to build a lot of weapons at a single TL, you'll probably want to do similar, as it can really speed up the design process (and once you have the equations, you'll have a clearer idea of what each adjustment does - I know that damage is linear with Caliber, Length, and Power, weapon weight scales as the cube of Caliber but linearly with Length and Power, and so forth).

As for radar, I don't think it's unrealistic for it to be able to see out to the horizon. Do note that detection isn't automatic within range - you still have to make a Sense roll (or, rather, a roll against some sort of operational skill, using the vessel's Comm/Sensor modifier).

Finally, Spaceships doesn't have options for modifying quality. Using the general rules from High Tech and the like will probably work out for you, however.

[Halinn]

Originally Posted by weby

As example of a large modern carrier. The base armor it has is really low compared to the damage dished out by any heavy weapon. Basically any antitank missile size weapon should be able to shoot holes in it. But it consists of thousands of water tight compartments and has good bilge pumps. So in real life being hit by even few hundred such weapons would likely hurt it a lot and might start some fires and similar secondary effects that might indeed destroy it, but the raw damage would just punch a lot of holes in the outer hull and it would still keep floating. But in gurps the extra damage that goes through the armor would just destroy it in short order(as in go over -10 times hitpoints).

That sounds like some flavor of semi-ablative armor to me.

[RyanW]

Originally Posted by weby

The newest warships have again a bit more armor, but it is partial coverage only protecting most vulnerable parts.

Actually, that was true in WWII as well, starting as early as the USS Nevada in 1912. The idea was to heavily armor the ammunition and the vital machinery, but allow shells to go right into (and very likely, right back out of) non-vital areas.

Now, it's mostly a matter of preventing incidental damage (mostly crew survivability in minor hits and near misses, and keeping them alive long enough to abandon, if necessary). With anti-ship missiles being the biggest threat (there are a lot of missile boats out there), and anything short of a battleship pretty much can't reliably soak one of those. Remember what Mr. Miyagi said: Best block, no be there.

[benz72]

Originally Posted by Halinn

That sounds like some flavor of semi-ablative armor to me.

Injury tolerance

[scc]

Actually I think that a new Advantage is required, primarily targeting things that meet the criteria in sentence two of paragraph three under Size of Target on B550. This would be a physical, exotic trait