Create a circular, closed spline and move the drone along it with a Timeline track.
Or add a Camera Boom, attach the drone to the boom, rotate the boom (which can be a Child Actor with a Rotating Component, for example).
Or use math to find a point on the circumference and set the drone’s location there (updated in Tick).
Or, the most simple solution, attach the drone to the Mothership, give it an axis offset and rotate locally (setting the offset can serve as an animation of the drone emerging from the hangar - so win-win)
All of the above should work OK. There’s probably more solutions, too - all depends how you want it to feel like, how modular the system needs to be and how much overall control is needed over the trajectory.
You could, for example, rotate a dummy, locally offset object (or rotate a vector on an axis) and have the drone chase the dummy using vInterp. The interpolation scale can be modulated over time, giving you smooth yet slightly unsteady movement; if that’s what you’re after.
Pick you poison.