Abstract
A new helicopter-type UAV has been developed in our research, which has stators just below the main rotor, instead of the tail rotor, to compensate the counter torque caused by the main rotor. In this paper, the blade number of the stators was reduced from 8 to 4 by optimizing the blade configuration and the control rigs were newly designed and manufactured in order to reduce the weight. Performance tests using ground test apparatus proved that the newly designed stators can compensate the counter torque at the same stator angle of attachment (25 degree) in the case that the rotor pitch angle is more than 7 degree. The maximum compensation torque was obtained at the angle of 40 degree. Moreover, the total thrust was hardly affected by the existence of stators.
