The following three points have been investigated for improving the flight performance of a multiple rotor drone. The first one is `collective pitch control', which enables rotors to change the thrust much quicker than the rotor speed control method．Furthermore, a negative thrust can be generated by the rotors with a negative collective pitch. The negative thrust can cause a large control moment for controlling the attitude. Then, the drone has high maneuverability thanks to the quick thrust change due to the collective pitch control. The second one is `decreases of the moments of inertia', which can enhance the maneuverability of the drone. The variation of moments of inertia has also possibility to decrease a motion of the drone due to a disturbance moment when a feedback control is adopted. The third one is `a rotor with small aspect ratio rotor blades', which generates a larger thrust caused by the larger chord length and the larger thrust coefficient.
