In the Star Fleet setting, what relationship do Impulse engines have to Tactical Warp motion? I ask because why would warp-capable ships care if their Impulse engines took critical hits? I've read the FTL page in ACTA:SF, but it still doesn't quite match up with the critical hit table. I'm almost completely ignorant of ADB's version of 'trek, so I'm sure I'm just missing some key piece of intuition.
I also ask because my kid, who I'm going introduce to ACTA:SF this weekend, is an ST nut (TNG especially), and will be driven mad by the technical differences in the settings if I don't have some handwave-ium ready.
My personal attempt to explain things would involve the "tactical warp" being more of an impulse multiplier if you will, where the warp bubble essentially neutralizes the ship's inertia so that the impulse drives can push the ship around precisely by the impulse drives. Full warp involves actually using the warp bubble to travel, which takes a lot more energy, etc.
I also ask because my kid, who I'm going introduce to ACTA:SF this weekend, is an ST nut (TNG especially), and will be driven mad by the technical differences in the settings if I don't have some handwave-ium ready.

My personal attempt to explain things would involve the "tactical warp" being more of an impulse multiplier if you will, where the warp bubble essentially neutralizes the ship's inertia so that the impulse drives can push the ship around precisely by the impulse drives. Full warp involves actually using the warp bubble to travel, which takes a lot more energy, etc.