PURPOSE: To provide increased acceleration resistance of an operator, in a seat device for aircraft operator, by installing a seat body through a rotational shaft, and disposing an actuator to change an installation angle of the seat body according to acceleration.

CONSTITUTION: Acceleration of an aircraft is detected by an acceleration sensor 7 and is inputted to a controller 8. The controller 8 outputs signals to a control valve 9 according to inputted acceleration and operates an actuator 6. Operation of the actuator 6 rotates a seat body 3 in the rotation direction of a rotation shaft 4, and changes an installation angle (a) of the seat body 3. With this constitution, it is possible to improve acceleration resistance of an operator.