Servoactuator includes a pair of double-acting linear actuators providing for 360.degree. controlled rotation of an output shaft. The rotary motion of the ouput shaft is employed to sequence high pressure fluid flow and return for the same to the respective ends of the respective actuators so that both actuators continuously develop output force except for end stroke points. Shimmy damping may also be obtained by a bypass-damping valve which comprises a shuttle movable to a first position by high pressure fluid for controlled operation of the servoactuator and to a second position by removal of the high pressure fluid to direct fluid flow between the respective actuators through a damping orifice.