Some questions on Spaceships

[Rysith]

Originally Posted by Ulzgoroth

It's fairly hard to justify countermissiles rather than point defense beams or cannon. (Except for countermissile nuking.) You could have 16cm countermissiles used to shoot down larger 'shipkiller' missiles, but it's difficult to make larger shipkillers useful.

Having a missile that counters an opposing, larger missile gives a ship a larger envelope in which to perform the intercept, and allows dedicated counter-missile ships to free up mass on other ships to mount more anti-ship weapons. It might end up below the resolution at which Spaceships operates, but in principle having a missile that could engage multiple opposing missiles may be useful - something like a 32cm laser head that can engage up to 16 incoming missiles.

How do you do 'surgical' a gigantic hypervelocity impactor?

You make it less gigantic and hypervelocity. Consider a missile intended to close at high speed and shower a target ship's engines (or other subsystem identified on or after launch) with 2cm kinetic projectiles while missing with the main body, gaining accuracy from the close approach but attempting to leave it drifting in space rather than a sphere of expanding plasma. It should even be possible to adjust the relative velocity of the projectiles depending on the desired probabilities of damage / crippled / destroyed results. That might be veering into the territory of tube-launched single-use drones rather than missiles, though in some sense there isn't much difference between the two.