Method of positioning a control surface to reduce hysteresis

A method of determining the actual position of a control surface (27). The method comprises receiving a signal (34) representative of a required position of the control surface (27), repositioning the control surface (27) in response to the signal (34) by moving an actuator (26), measuring a secondary position indicator, calculating the actual position of the control surface (27) on the basis of the secondary position indicator and, comparing the actual position with the required position.