Wind turbines need mechanisms to yaw into the wind and furl or stall blades to regulate speed. Yawing mechanisms have included tail vanes, fantails, and electronic drives. Furling mechanisms include horizontal and vertical furling to reduce rotor area, coning, variable geometry, and blade pitching. Passive stall and mechanical brakes provide overspeed protection. Small turbines often use tail vanes and passive stall while large turbines employ active yaw drives, variable pitch control, and mechanical brakes.

1. WTG Yawing and Furling Mechanisms Maree

7. Edmund Lee, a millers friend, the blacksmith who invented the fantail An embarrassed millwright Powered by the wind? Well I never... ... the axillary rotor, set at right angles to the sails, harnesses the crosswind to turn the cap of the windmill to face the wind, automatically... freeing the miller from the job.