IR Susceptibility of Supersonic Aircraft according to Omni-directional Detection Angle

Infrared guided weapons act as threats that greatly degrade the survivability of combat aircraft. Infrared weapons detect and track the target aircraft by sensing the infrared signature radiated from the aircraft fuselage. Therefore, in this study, we analyzed the infrared signature and susceptibility of supersonic aircraft according to omni-directional detection angle. Through the numerical analysis, we derived the surface temperature distribution of fuselage and omni-directional infrared signature. Then, we calculated the detection range according to detection angle in consideration of IR sensor’s parameters. Using in-house code, the lethal range was calculated by considering the relative velocity between aircraft and IR missile. As a result, the elevational susceptibility is larger than the azimuthal susceptibility, and it means that the aircraft can be attacked in wider area at the elevational situation.

Simulation and analysis of hot plume infrared signature based on SNB model

Numerical calculation of infrared emission from hot plume is of great significance for flight monitoring and detections. In this paper, the SNB (statistical narrow band) model established with parameters derived from the high-resolution spectral database HITEMP 2010 is used to perform the hot plume infrared signature simulations. Accuracy of the model is examined by the exact LBL (line by line) method, which proves the model’s reliability to predict radiative properties of combustion gases. In the application part, the SNB model is used to analyze infrared signatures of aircraft plumes cruising at different flight altitudes. The results show that cruising at a higher-altitude will obviously reduce the plume infrared emission. Besides, the plume infrared emissive energy mainly concentrates in a special wavenumber interval and can be strongly absorbed by atmosphere.