[Spaceships] A reevaluation of missiles and point defense

[Ulzgoroth]

In light of the understanding that attacks are fully resolved one at a time, and the inference that point defense gunners can fire in sequence rather than in parallel, I've done some new missile combat numbers.

Calculations are based on TL9. TL 10 should benefit the defender significantly due to improved laser RoF. Higher TLs will benefit the attacker, but not much in the basic case as missiles are quite sufficiently accurate already. Everything uses 20-second turns, because longer ones don't make sense to me for gunnery. I believe they would usually harm missile-users, but 1-minute turns might benefit them.

Non-fragmenting missiles, including nukes, are poorly matched against PD. Even with only skill 12, a three-way split-fire from a VRF laser is expected to kill better than two missiles. With skill 14, splitting four ways brings this up to almost three. Nuke strikes are only viable against targets with extremely poor point defense. If a large vessel can't protect itself, SM+5 to +7 point defense drones/escorts can cover for it.

Proximity nukes are pointless. The only way you'd miss (outside 17-18) with a missile is if you were attacking a small target with ECM, in which case you shouldn't be using nukes in the first place.

Fragmenting missiles do better. With skill 14, it takes approximately one full point defense gun's fire, in two or three way split, to shoot down each missile's 10 fragments (all of which usually hit). They don't scale as well as beams, but pack a punch. Even at SM+15, each fragment of a tertiary missile hits almost as hard as a major beam (at higher TL, armor divisors may change this). Since point defense guns require power (making them 50% bulkier than missiles at TL9, 25% later), ships may have to rely on smaller craft to stop heavy missile volleys, and thick plating to keep out the common, PD-saturating 6dx8 16cm missile.

Small craft will need a different approach to missile survival. I suspect SM+5 units with ECM may be the solution, but have not done the math for them.