Okay. I would first check if any of the Input Keys I setup(Wheel, pedals, etc) work with your joystick. If you’re missing some Input Keys for the joystick, I would then try to figure out which variables correspond to the joystick’s pitch, roll, and yaw. You can do this by using the Get Wheel State function every frame and seeing which variables change when you move the joystick. Once you’ve discovered the corresponding variables, you can use them to adjust the pitch, roll, and yaw of your flying vehicle.
Edit: have you tried seeing if the generic usb inputs Epic added in 4.15 work with the joystick?