Abstract: Provided are a wind tunnel balance calibrator capable of improving accuracy of attitude control of a wind tunnel balance, and a wind tunnel balance calibrator which can ensure a wide work space around the wind tunnel balance. A wind tunnel balance calibrator includes a load application mechanism for applying a load to a wind tunnel balance and an attitude restoration mechanism for restoring an attitude of the wind tunnel balance. The attitude restoration mechanism is constituted by a parallel-link mechanism including a support plate for supporting the wind tunnel balance, and actuators capable of displacing the attitude of the support plate with six degrees of freedom.

Abstract: Provided are a wind tunnel balance calibrator capable of improving accuracy of attitude control of a wind tunnel balance, and a wind tunnel balance calibrator which can ensure a wide work space around the wind tunnel balance. A wind tunnel balance calibrator includes a load application mechanism for applying a load to a wind tunnel balance and an attitude restoration mechanism for restoring an attitude of the wind tunnel balance. The attitude restoration mechanism is constituted by a parallel-link mechanism including a support plate for supporting the wind tunnel balance, and actuators capable of displacing the attitude of the support plate with six degrees of freedom.

Abstract: A blade root portion of a rotor blade is attached to a rotor head for rotating. A center portion linearly elongates from the blade root portion. A blade tip portion outward elongates from the center portion and has a shape which is defined by a leading edge, a side edge and a trailing edge, and has a predetermined aerofoil. In the leading edge of the blade tip portion, a swept-back angle &lgr;(r) at a distance r from the rotation center of a rotor satisfies relational expression (1) of a rotor blade length R of a rotorcraft, a maximum flight Mach number M∞ which is a flight limit speed of the rotorcraft, a blade tip Mach number MTIP which is a tip speed during hovering, and a drag divergence Mach number Mdd which is determined from the aerofoil of the blade tip portion.

Abstract: A control system has an HHC actuator having a basal portion and a movable portion. A load acting on the control system is detected by a semiconductor gauge. The load detected by the semiconductor gauge is compared with a threshold value in a computer. If the detected load is larger than the threshold load, the movable portion is fixed to the basal portion by a fixing mechanism. By detecting the sign of stall of blades, the HHC actuator is fixed in a neutral position, allowing safe flight. A fixing switch is provided for allowing the fixing mechanism to operate regardless of the result of the comparison with the computer.