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Aerodynamic noise level has become an important performance index of civil aircraft, and it is drawing more and more attention. Most airframe noise research based on CFD method is aimed at aircraft individual parts at present, while lack of noise prediction for the complex high fidelity full aircraft model. Due to the interaction between aircraft parts, noise prediction between single part and the actual configuration are very different in the aspect of calculation conditions, noise generation and propagation. Only by using more realistic model can the noise be accurately predicted. In this paper, high-resolution mesh and high-precision hybrid RANS/LES method, combined with the FW-H acoustic analogy method, are employed to predict the noise of a turboprop's high-fidelity 1/6 scale model of landing configure. The improved delayed detached eddy simulation (IDDES) method was used to simulate the flow in the near-field sound source region, and the sound source characteristics of the whole turboprop are obtained. In addition to the two important noise sources-flap side edge and wing tip, numerical simulation also found other two important noise sources resulting from the interaction between parts-interaction between nacelle wake and flap, and the complex flow between flap inner side and fuselage. Results of far-field noise show that in the longitudinal symmetry plane of the fuselage, the noise mainly propagates to the lower front and over back direction, and the dipole characteristics are very obvious. In the plane perpendicular to the incoming flow, the noise in the transverse direction is weaker.

The long-range strategic bomber’s stealth performance and plan track strategic call more and more attention. By comparing the stealth performance of next generation stealth bombers developed by the United States and Russia and their faced threats, higher performance requirements of the new generation of stealth bombers have been proposed-full spectrum, all directional stealth technology, such as radar stealth, infrared stealth and radio frequency stealth. High stealth strategic bomber penetration measures are also summarize, including more advanced stealth technology, system support, the high altitude penetration, equipped with self-defense weapons.

The accurate measurement of air data is critical for the navigation and flight control of vehicles. Comparing with the intrusive conventional air data measurement system, the flush air data sensing system is more suitable to hypersonic vehicles, stealth vehicles and high angle of attacks vehicles. The development of the flush air data sensing system is reviewed. The components of the flush air data sensing system are introduced. Four key technologies during the application of this system(pressure ports arrangements, aerodynamic models and solution algorithms, calibration algorithms, the failure detection and management) are proposed. Based on the different application schemes on different vehicles abroad, different application modes of these four key technologies are analyzed. These four key technologies are tightly related to the accuracy and reliability of the system. Finally, the applications of the flush air data sensing system to future aeronautical/astronautical vehicles are prospected.