This paper describes a passive regulator for the angular velocity of a small wind-turbine: it consists of a rigid short tail with an aerodynamic rotating vane to yaw the rotor smoothly edgewise to the wind direction in strong winds or in gusts, a bumper and a spring. This regulator reduces gyroscopic loads, is easy to adjust and can be manufactured in smaller sizes and is much stronger than conventional vanes used in small wind-machines. Besides, the energy collected with it is greater. Field test results indicate that its behavior agrees well with simulations, and that the regulator can be advantageously utilized, as compared with conventional vanes and other mechanical or electromechanical means, in horizontal axis wind-turbines with diameters between 2 and 12 m. (C) 2003 Elsevier Science Ltd. All rights reserved.