In this paper, the part of the cockpit of the air vehicle in a far field with a plane wave of warning, scattering fields from cockpit part is assumed to be radiate in free space. Fuselage of the air vehicle is modeled finite elliptical cylinder and a large cavity is mounted in the sidewall of a finite elliptical cylinder. The part of the cockpit of the air vehicle is modeled close to the real model. A Radar Cross Section (RCS) analysis of cockpit part is calculated using together Shooting and Bouncing Ray (SBR) and Geometrical Optics (GO) methods and RCS analysis of elliptical cylinder is calculated Uniform Geometrical Theory of Diffraction (UTD) and Physical Optics (PO) method. Shooting and Bouncing Ray (SBR) using for analyses does not limit the form of model. By using of proposed method, outputs for cockpit part and fuselage RKA analyses were provided.