thurgie the middle size will fit will be a little extra hanging off the ends bit width is fine

thurgie lot of silly answers here ... yes you can use them to power a drone but you need to know the max amps the motors will pull ... for bigger drones you can run then in parallel as well as series so 4s4p will give u a 6000mah with 40A discharge but your using 8 batteries instead of 4 ... you can also put a throttle limit in so you don't pull too much from the battery... if you pull too much in 1 go the drone will reboot and fall out of the sky

thurgie using a s-bus reciver 1 wire from your reciver plus power and earth then all the servos plug into the flight controller instead of the reciver