The influence of helicopter tail rotor parameters on RCS

Abstract

High requirements have been placed on the stealth performance of armed helicopters during wartime missions，in order to reduce the probability of the helicopter being found during the task，based on geometric optics method and consistent diffraction theory，the effects of different tail rotor profile thickness，curvature and tail rotor scissors angle on RCS are studied. By comparing different parameters of the tail rotor and the RCS peak value and mean value of the coated absorbing material，the conditions which are more favorable to the stealth of the helicopter tail rotor are determined. When viewed from the ground，the RCS with small tail rotor thickness and small curvature will be reduced appropriately，and the change of scissors angle will lead to the change of RCS peak phase. When the radar is irradiated in parallel，the RCS of tail rotor with smaller thickness is smaller，and the RCS peak value of tail rotor with smaller curvature is smaller. Applying wave absorbing materials on the leading edge and tip of the blade can effectively reduce the overall RCS of the blade. Comprehensive analysis shows that by using the smaller thickness and curvature of the tail rotor，it is beneficial to reduce the RCS of the helicopter tail rotor，and the blade tip surface and the blade leading edge of the absorbing material coating can effectively reduce the overall RCS.

Keywords

• tail rotor
• radar cross section（rcs）
• high frequency approximation method
• stealth