You don't need Armored Assualt, but get it if ya want ot.
The books have attack tables for large Mk weapons. Ships have hits equal to their tonnage. The crits are handled just like arms law crits with additional hits and negatives to activity, systems damaged or knocked out, etc. Just like in melee, a fight will consist of exchanging fire and PC's trying like mad to make repairs on the fly.
There are many ships systems to track and damage.
Engines; reduce max speed and penalties to mnv. Many instant death crits can be described as reactor breech (and avoided if PC's can make hard/very hard/etc mnv to eject reactor core...if not far enough away, roll additional Mk 20 Nuclear Bomb attack and radiate crew. Scifi is FUN).
Life support; life support failure happens in stages and results in penalties to PC activity due to smoke, lack of oxegen, on bard fires, etc.
EM stations; these provide additional DB for the ship and depend on PC/Computer operation. Rate the system for computer operation (always provides +20 DB/etc) versus PC operation(which is expressed as a maximum DB, with the total bonus provided dependent on player skill checks/dice rolls).
Weapons; damage them, reduce their effectiveness via OB penalties or Mk lowering or both. Turrets can become fixed or even turn randomly, providing a random firing arch every melee. Weapons can get stuck on auto fire...when turret weapon spins randomly and fires continuously, eventually it will target the ship it is mounted on...scifi is FUN. Hope that armsman has a weapons tech skill, word processing or programming skill to make repairs with as the cabin fills with smoke and the bad guys keep shooting.
Power Plant; affects everything and I assume any GM will use that fact to full dramatic liscence. Remeber, scifi games are FUN.
Hits: equal to a ships tonnage, when hits are zero, ship is out. The superstructure remains, and a ship can mnv slowly/drift. As long as life support is up, crew will be ok. I give infrastructure hits equal to 1/2 AT. If a ship takes it hits plus infrastructure hits, it is absolutely destroyed (no salvage).
Systems; there are lots of systems on a ship. Sensors are the most common. Data files/computers, astro navigation, communications, holo grids, launch bays/shuttles, elevators if its big enough, etc. be ceative (sensors are by far the most often damaged, if for no other reason than being blind is so much fun).
