system
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human
[Firefly] How does the artificial gravity work on a Firefly class ship?

Most ships use artifical grav systems that work as a utility on the ship which allows it to be turned on an off. However, on a Firefly this doesn't seem to be the case. When Serenity cuts power to all systems, the gravity seems to still stay on. For instance, that time they were looting that blown out carrier and the Alliance almost caught them I remember Mal telling Wash to shut down everything but the air. Also, the time Serenity ran Out of Gas, all the systems including the air shut down, but the gravity never stopped working. I always wondered why they didn't reroute power from the grav system to the air supply.
gpt
The Firefly class gravity comes from a rotating ring just aft of the ship's midsection. It produces a gravity field using the “Peristere Principle,” that also acts as a momentum dampener to allow passengers more freedom of movement during all aspects of flight. (Can you imagine pulling a "Crazy Ivan" without one?)


What this means is that the grav system can't simply be tuned off or on instantaneously. It's like a big hearing coil in that regard--it takes several hours to "warm up" and many more to wind down. So when they ran out of gas or shut off the power, that included the grav, but there was enough residual effect to keep them from floating around, even after a number of hours.