[Ulzgoroth]

Originally Posted by Crystalline_Entity

What would subsurface warfare look like at TL10? There’s a notable lack of effective underwater weaponry in Ultra-Tech, no torpedoes, and even blue-green lasers have rather lacklustre performance underwater, though the supercavitating mini-sub can mount a blue-green strike laser (according to the text on UT228, I'm not sure if this is useful though).

Most likely torpedoes, probably including super-cavitating ones. Sonic weapons might possibly work as well, but very likely not practical.

Originally Posted by Crystalline_Entity

Would Point Defence Lasers (UT115-6) be a viable defence against brilliant or genius TL10 missiles such as the hunter and striker missiles from UT168?

In theory, missile smarts should have a lot of trouble outrunning speed-of-light weapons.

On the other hand, GURPS hasn't got rules that are particularly supportive of point defense...

IIRC, the 'point defense lasers' in Ultratech are quite low RoF too, which seems quite bizarre - it's not like you need huge damage to mess up a missile, and even if you could under the rules autofiring lasers are great at doing lots of damage to poorly armored targets

Originally Posted by Crystalline_Entity

Pyramid 3/37: Tech and Toys II introduces additional heavy weapons on p.22-27, including a 160mm indirect fire railgun, what sort of role would this play compared to missiles?

Shooting defenseless targets, most likely. I'd expect TL10 sensors to have little trouble picking up 16 cm shells, and ballistic flightpaths make them come over the horizon at you high and dumb for easy point defense.

Originally Posted by malloyd

Armor is not likely to get much better unless you can make it out of something other than atoms. And anything that can shoot through water can probably shoot through armor too. Armoring against incidental threats is still worthwhile - it'd be really embarrassing to lose a warship to drug smugglers with a machine gun - but as a defense against serious heavy weapons it's already fairly limited.

Accurate or not, GURPS Ultratech definitely disagrees with the idea that armor won't improve.

I don't think it suggests that the balance of penetration could swing back in favor of massively-armored battleships though.

Originally Posted by malloyd

The same point defense as against missiles fired from nearby? There's nothing especially magical about orbit.

An orbital strike is almost unavoidably going to be coming in very fast, and is consequently more likely to use a heavy solid impactor rather than a lighter warhead, adding up to something relatively hard to stop. You could make a surface-launched orbital-velocity range kinetic-kill missile, sure, but it'd take an awful lot of rocket.