Unlike vehicles, Starfinder already has a pretty complete set of Starship rules, though, if you’re not careful, starship battles can be very, very one-sided with the current Starship combat rules, which probably need a bit more variability and breadth to become fully functional.
You could probably extend the vehicle rules I created by expanding the various tables later in the design process, in order to make truly tiny starships, though I imagine the power demands for a Drift Engine would make this non-viable.
Ship’s frames don’t really take into account whether they can operate in an atmosphere well or not and thrusters are the only place where the topic of take-off and landing are even broached. A spaceship with flight frame is going to find it easier to take off, land and manoeuvre in-atmosphere than a Voganesque space-brick. Applying a flight-frame to a ship should probably use up expansion bays (though can be fitted to ships small enough that they don’t have one to offer). It would apply a +2 bonus to Piloting skill rolls and AC while in-atmosphere, including a bonus to Target Lock.
- Small – 1 Bay
- Medium – 2 Bay
- Large – 3 Bays
- Huge – 4 Bays
- Gargantuan – 5 Bays
- Colossal – 6 Bays
In lieu of armour designed to deflect, a ship can elect to reinforce its hull. This can be combined with standard armour of course.
- Mk1R +1 DT, -1 TL, Cost: 7 x Size Category
- Mk2R +2 DT, -2 TL, +1 Turn Distance, Cost: 21 x Size Category
- Mk3R +3 DT, -4 TL, +3 Turn Distance, Cost 45 x Size Category.
A ship can raise its CT by building in redundant systems, multiple conduits and routes for energy and data. This does make the ship’s EM signature much higher and is costly, but can make ships incredibly tough.
- Basic Redundancy: +1 CT, -1 TL, Cost: 7 x Size Category
- Double Redundancy: +2 CT, -2 TL, Cost: 21 x Size Category
- Triple Redundancy: +3 CT, -4 TL, Cost 45 x Size Category.
A ship can also be fitted with plates, foam, baffles and even water tanks, designed to absorb and dissipate incoming energy. This armour can be combined with other forms of armour.
- Basic Ablation: +1 HP Increment, -1 TL, Cost: 7 x Size Category
- Military Ablation: +2 HP Increments, -2 TL, +1 Turn Distance, Cost: 21 x Size Category
- Advanced Ablation: +3 HP Increments, -4 TL, +3 Turn Distance, Cost: 45 x Size Category
Expansion bays are pretty well covered, but there are a few things missing that might be useful to add.
External Ship Clamp: PCU 4, BP 2
An external clamp to which a Tiny scale ship can attach and from which crew can enter and exit. The external ship is not protected and can be freely targeted by enemy vessels. This does not use up an Expansion Bay but a ship can only have a number of clamped attachments depending on its size: Small 1, Medium 2, Large 4, Huge 8, Gargantuan 16, Colossal 32.
External Shuttle Clamp: PCU 5, BP 2
As a ship clamp, but for Small vessels.
External Pod Clamp: PCU 1, BP 1
You can attach an expansion bay to the outside of your ship as a pod. This is most especially used for carrying cargo, but other pods can be attached. This acts exactly as other clamps, but the exterior pod will also need power and will have to have its cost paid. Pods are vulnerable to attack and typically have 20 ship-scale hit points. They’re considered Tiny, ship-scale, objects.
Rather than soaking up damage, a shield can be more of a ‘deflector’ shield, surrounding the ship and causing attacks to curve or deflect away or around it. These shields cannot be combined with other shields, due to interference, though a ship can have both and switch between them.
- Deflector I: AC +1, PCU 20, Cost 6
- Deflector II: AC +2, TL +1, PCU 30, Cost 15
- Deflector III: AC +3, TL +2, PCU 55, Cost 23
- Deflector IV: AC +4, TL +3, PCU 110, Cost 32
Pretty well covered, especially if we consider the ramming rules to scale accordingly, but that brings up something else…
A ram prow is a heavily armoured ‘beak’ on the front arc of the vessel. It increases ramming damage caused by the vessel while also reducing the damage that it takes from ramming.
- Light Ram Prow – Light Weapon +2d4 ram damage & damage reduction, DT +1 (Front arc only).
- Medium Ram Prow – Heavy Weapon +5d6 ram damage & damage reduction, DT +2 (Front arc only)
- Heavy Ram Prow – Capital Weapon +6D8 ram damage & damage redution, DT +3 (Front arc only)
Rams use no power and cost 1, 4 or 10 BP respectively.
A ram can be fitted with a boarding tube for boarding actions at a cost/PCU of 1, 2 or 3 respective to size.
Rams can also be powered, making them ‘jaws’ that can grip onto a ship or even ‘chew’ it. Gripping requires contested piloting rolls to escape, chewing allows a second, immediate ram attack after the first hit, but releases the vessel. You can also elect to save that attack until your next turn – so long as you are clamped on. A powered ram costs an extra 5/10/20 PCU and 2/4/8 BP.