Lyran Commonwealth Navy: Depressurized Operations.
Factions this is available to:
Lyran Commonwealth, Taurian Concordat.
Mechanics of it:
Critical hits only score on 12 or higher on 2D6, and only inflict 1 crit, if the crit is missed on the location, it's considered 'used' and may not be re-rolled. Damage to Life support does not apply at all to combat beyond adding one additional system in need of repair for repair rolls, or as a system that must be repaired after-battle in campaign play.
Further;
Critical damage may be 'jury rigged'/repaired during battle on a successful PSR plus the number of critical injuries taken. (for example, a ship with 1 critically damaged system may make a PSR plus 1 to repair it, while a vessel with 4 critical damage not already repaired needs PSR plus four to repair 1 system).
Why of it?: Through most of the civilized galaxy, naval vessels operate at 1 atmosphere pressure and a shirtsleeves environment when going into combat. The Terrans did it, the Rim Worlds did it, Davion, Liao, Marik,Kurita, and the Clans do it this way.
Starting in the post-Clan invasion era, the LCN (LAN) started doing things a little differently-they started dumping the atmosphere before the fight gets going, and fighting their ships 'at ambient pressure'. This has several useful knock-on effects:
1. Fires and shockwaves don't propogate through vacuum. This prevents the bulk of critical damage from impact hits and limits the spread of damage inside the vessel. it also prevents the catastrophic rupture of the pressure hull, and reduces the cost to repair damage post-battle.
2. It makes combat damage control MUCH EASIER.
Downsides:
1. Crew costs and crew training in campaign multiply by 1.5 to 2.5 depending on branch. (Jumpship/Warship crew cost 2.5, Dropship crew cost 1.5).
2. This doctrine does not extend to dedicated transport dropships for ground assault.
Intent: This doctrine allows LCN vessels (Dropship or larger, but not transport dropships) to absorb damage well in excess of an equivalent vessel, effectively turning them into 'zombie' units able to keep going until Structural integrity is completely lost at near full capability, and it also speeds repair and recovery post-battle as the damage from even very large hits did not spread.
I admit, this one is out of my own vanity project, and I'm probably missing some logical outcomes with it, but I wanted to keep it relatively simple to implement without going past the point of grossly OP compared to the other Doctrines/SFA's posted here.
so, any thoughts to refine this?