from processor 47 however provides a finer more responsive level of control based on the immediate wind condition at the blade thus where the number of sensors indicating turbulence exceeds a predetermined value and continues to do so for a predetermined period of time the processor 47 instructs the pitch controller 50 to reduce the pitch until the number of turbulence sensors which indicate turbulence falls below the predetermined number in this way the pitch of the blade can be controlled in real time and be responsive to the measured turbulence of the air flow across the blade in further examples the data from the plurality of sensors mounted on the blade surface can be used to monitor the performance of a wind turbine blade in real time from the perspective of the blades aerodynamic design by transmitting data from different turbines to a central store for analysis sufficient data could be collected about the air flow performance of the wind turbine blades allowing them to be improved in future re designs in alternative applications the turbulence sensor described above can be applied to the control of further wind turbine rotor blade aerodynamic parameters such as rotor blade shape and rotor blade air flow this will now be.