A closed-loop control scheme for dynamic stall over an airfoil section from Bell Helicopter is presented. The detection scheme relies on the ability to detect the growth of an unsteady disturbance placed in the flow at the leading edge of the airfoil as flow separation occurs. The unsteady pressure signal is then acquired by an on-board pressure transducer at a nondimensional chord location of x/c = 0.0865. Analog circuitry then gains the signal, bandpass filters it around the frequency of the disturbance, and computes the RMS value of the filtered signal, giving a DC voltage representation of the spectral energy of the signal. Based on the RMS value of the signal, the circuit decides whether to leave the actuator in its low-powered "sense state" producing a disturbance or to change the actuator to its high-powered "control state", with enough power to reattach the flow over the airfoil. Baseline measurements were taken for freestream velocities ranging from U∞ = 10 m/s to U∞ = 50 m/s and stall penetration angles of three, seven, and ten degrees. These results were then compared to open-loop unsteady actuation control as well as various levels of closed-loop actuation control. The performance of the closed-loop scheme was measured by its effect on aerodynamic quantities, namely the change in cycle-integrated lift and cycle-averaged aerodynamic damping. In terms of cycle- integrated lift, closed-loop control produced a relatively constant increase for different stall penetration angles at a specific velocity, while showing a lessening increase in lift as velocity increased. At the lowest velocity, there was approximately a 15% increase in lift which dropped to a 1 − 2% increase in lift at the largest velocity. In terms of cycle-averaged aerodynamic damping, the ten degree stall penetration case showed a relatively constant 50% increase across all freestream velocities, while the three degree stall penetration case showed a decrease from approximately 150% to approximately 5% as freestream flow velocity increased from 10 m/s to 50 m/s. The seven degree stall penetration case showed a blending of these two cases for the cycle-averaged aerodynamic damping. It was also found that for each velocity and stall penetration case, there was an optimum amount of actuator control time that gave the best increase in both cycle-integrated lift and cycle-averaged aerodynamic damping.