To generate a high dynamic lift needed for takeoff and landing in jetting a jet stream in the circumferential direction of an outer peripheral sur face of a cylindrical body by providing a shift mechanism to shift the cylindrical body from an operating position disposed in a rear edge of a main blade to a housing position in the main blade.

A coanda effect-high dynamic lift generator disposed in a rear edge of a main blade 1 moves a cylindrical body 4 by a link mechanism 2 driven by an actuator 5. Namely, in a cruise or the like needing no generation of the high dynamic lift, the cylindrical body 4 is housed in the tip of the link mechanism 2 collapsed into a fair ring 7 of the main blade. On the other hand, in the takeoff/landing needing the high dynamic lift, the cylindrical body 4 is shifted to the rear edge side to be projected below the rear edge of the main wing 1. Engine exhaust introduced through a duct in the main blade 1 is jetted circumferentially of the outer peripheral surface of the cylindrical body 4, so that a stream on the main blade is induced to generate a circulating stream and generate a large dynamic lift even in low speed.