Patent ID: 6749152
Filing Date: 2004-06-15
Classification: B64C,Y02T

Abstract:
A method for avoiding a collision of a rotating rotor blade of a rotary-wing aircraft with a blade vortex, the method comprising:acquiring a noise signal spectrum using a measuring element disposed on the rotary-wing aircraft; converting the noise signal spectrum into electrical signals and transmitting the electrical signals to a signal processing device; determining a harmonics value of a blade repetition frequency of the rotor blade from the electrical signals using an analysis device of the signal processing device, determining a blade vortex interference index value by calculating a quotient from a typical blade vortex interference harmonics value and the determined harmonics value; determining an averaged blade vortex interference index value; supplying the averaged blade vortex interference index value as a signal characteristic quantity to a threshold-value device; signaling a blade vortex interference using the threshold-value device when the averaged blade vortex interference index value exceeds a first threshold value; upon the signaling of the blade vortex interference, determining a minimum of the blade vortex interference index value by an optimization process using a closed-loop control device; upon a determining of a temporally persisting minimum, providing flight state identification data from a flight state identification device to at least one of the threshold value device and the closed loop device; deactivating the closed-loop control device and switching the closed-loop control device to a stand-by state when the flight state identification data shows a flight state not typical of blade vortex interference; and generating an actuating signal for a final control element disposed on the rotor blade so as to influence an aerodynamic parameter of the rotor blade.