I don't know about today, but early Falcon 9 gridfin actuators used an open loop of RP-1 as the working fluid as well. It would drain into the tank, and be burn

I don't know about today, but early Falcon 9 gridfin actuators used an open loop of RP-1 as the working fluid as well. It would drain into the tank, and be burned in the engines on descent.