Abstract: Method, apparatus, and sensor mast for airfoil aerodynamic performance monitoring are based on pressure measurement. Pressure transducers mounted within the sensor mast measure real-time pressure, to produce an output signal. The signal is separated into steady state and overlaid ripple components. The steady state component corresponds to the mean dynamic pressure of the airflow, while overlaid ripple component corresponds to the superimposed turbulent flow component. The overlaid ripple component is transformed to an amplitude equivalent. A dimensionless ratio of the two components forms a pressure turbulence intensity factor, which may be used consistently to predict and warn of imminent stall conditions. Pressure measurement was found to be an improvement over airspeed measurement. Pressure sensors proved more robust and less fragile than airspeed sensors.