A trade-off analysis between lateral/directional stability and radar cross section requirements of an air-to-air combat airframe

Abstract

Numerical aerodynamic and radar analyses were conducted on 3 low-radar cross-section airframes, derived from the AVT-183 diamond wing. The geometries were developed by adding different configurations of vertical stabilators, to improve lateral and directional characteristics at high angles of attack whilst minimising the deterioration of radar signature characteristics. The analyses were conducted at a Mach number of 0.30, with angle of attack varying between 0 deg to 30 deg and angle of sideslip varying from 0 deg to 6 deg. Monostatic radar cross-section analysis was conducted in L and X bands. The study explored the trade-off between radar signature control (RCS) and the spin/departure requirements typical of a modern combat aircraft designed for air-superiority. Several of the proposed configuration were shown to improve both lateral and directional stability, whilst maintaining acceptable RCS.