Effects of radar absorption materials application on stealth performance of inlet based on risk theory

One significant technical measure to reduce the forward radar cross section (RCS) of the aircraft was to design the inlet into an S-shape. Additionally, the application of radar-absorbing material (RAM) can further decrease the RCS of the air intake which approach enhances the stealth capabilities of the aircraft. Nevertheless, the use of RAM will simultaneously increase the inherent weight of the air intake. The electromagnetic scattering characteristics of Sshaped inlets without RAM coating and seven coating schemes are calculated by numerical simulation. The risk theory was employed to assess the impact of the coating RAM on the radar cross-section. The simulation results indicate that coating RAM can further reduce the forward average RCS value. Compared to the full coating scheme the S-shaped inlets with RAM on the intake region can achieve 90% of the RCS reduction effect and cut down approximately forty percent of the coating.