I'm considering building a remote control fire engine with a working water pump. Has anyone here rigged a water pump or hydraulic pump or air compressor for remote control? Where should I search for affordable, small water pumps that are easy to integrate into fixtures? I thought about using a fountain pump, since they're easy to find, but I don't know if fountain pumps get damaged as the water supply runs out and they start pumping air, since they're designed for continuous water use. Another consideration is wiring/power. I could hook the fountain pump's 'ON/OFF' switch to a linkage for a servo motor, but that's not very sophisticated. I'd rather control the voltage to the pump the same way an electric RC car controls the voltage to the drive motor. A potentiometer might be overkill, but controlling the amount of power going to the pump motor would affect the water trajectory and allow for more options for the operator to play with. I'd probably put the water thru a compressing valve for extra speed. I want the water to shoot at least 4 meters. Given that this project could take months to complete, I'm on the fence about whether to begin, but I appreciate any advice/comments nonetheless. I've never built an RC vehicle from scratch, but I did lots of hardware/electrical/electronics work for the Robotics Club at my engineering college, so I know how to plan circuit diagrams, crimp/solder wires, read performance curves to choose gear ratios for motors: all that jazz, and I know a decent amount of fluid mechanics. Radio control is something I never learned about in theory or practice. If you guys could recommend a good hobbyists' book for that, that would be awesome.