To provide a flying object design system in which a disturbed air flow is processed in response to a temporary condition, an air flow generated at a surface of predetermined location in a flying object is regulated, a flow regulating efficiency is increased, both simulation for the generated disturbance flow and simulation of ultrasonic radiation for reducing a disturbance flow are carried out and a design including the ultrasonic generating device is carried out.

This ultrasonic generating device comprises an air flow detecting means installed at a flying object receiving air flow while being moved in the air to detect air flow data generated at a surface of predetermined location of the flying object, an ultrasonic generating means for generating an ultrasonic wave in correspondence with an air flow data detected from the air flow detecting means, and a calculating and processing means for generating a sound signal for generating an ultrasonic wave corresponding to the air flow data outputted from the air flow detecting means and in correspondence with the air flow data at an air flow data detecting location and for applying a driving instruction to the ultrasonic generating means.