PURPOSE: To increase safety in traveling by providing an auxiliary moving blade in addition to a moving blade so that a yawing due to a lift generated by a canopy and a moving blade can be canceled by a lift generated by the auxiliary moving blade in a wing canopy provided with a canopy on which the moving blade is provided.

CONSTITUTION: When a steering wheel is turned, for example, clockwise, a switch bar is turned on through a worm gear and a sector, a directional control valve provided in a hydraulic circuit for moving blade driving, and a moving blade 1 and an auxiliary moving blade 20 arranged at the rear of a canopy 2 through a cylinder are rotated counterclockwise. By this, when a car is turned at a high speed, a yawing due to a lift generated by the canopy 2 and the moving blade 1 is canceled by a lift generated by the auxiliary moving blade 20. Then a centrifugal force generated at the turning of the car is reduced so that the car can be turned stably. When the steering wheel is returned back to the neutral position, the moving blade 1 and the auxiliary moving blade 20 are also returned back to the neutral position.