A brake assembly for use with a wind turbine. The brake assembly comprises a movable wind flap for attachment to a tail assembly of the wind turbine, the wind flap being configured to assume a first closed position during normal operation, and a second open position when incoming winds exceed a predetermined velocity threshold. Provided on the wind flap is a trip rudder assembly for cooperating with incoming wind to urge the wind flap into the open position. A counterbalance assembly is also provided for biasing the wind flap into the closed position. The wind flap in the open position effects a redirection of a portion of the incoming wind, urging the wind turbine to assume an oblique position relative to the incoming wind, effecting a reduction in rotational velocity of the wind turbine.