Experimental Study of RCS Reduction for a Helicopter Inlet

An experimental study of RCS reduction for a helicopter inlet syncretized with engine cabin was completed in vertical and horizontal polarization ways.Meanwhile,the RCS reduction effects were analyzed for various reduction schemes by comparing with RCS of pure metal model.The results show that RCS of this inlet is lower than that of the pure metal model.Sticking radar absorbing materials on front lip,upper lip,inferior lip,output shaft,and engine cabin has best RCS reduction effect.This method can achieve about 8 dB of RCS reduction.Besides,the effect of RCS reduction in vertical polarization way is better than that of in horizontal polarization way.