Experimental aerodynamic assessment and evaluation of an agile highly swept aircraft configuration

Abstract

Extensive experimental and numerical investigations on a highly swept generic unmanned combat aerial vehicle (UCAV) configuration of lambda type with a variable leading edge contour have been conducted. Within these investigations, it was shown that the flow field is dominated by complex vortex systems including vortex-to-vortex and vortex-to-boundary layer interactions. The vortex-dominated flow field has a strong nonlinear influence on the aerodynamic behavior of the configuration. Hence, controllability is demanding and poses a real challenge in the design of these kinds of configurations. Especially, the dimensioning of the control surfaces, for the lateral- and longitudinal stability of tailless configurations of low aspect ratio and high leading-edge sweep, poses a challenging task which is not yet solved. To understand the problem of lacking lateral- and longitudinal stability for these kinds of configurations, experiments in the subsonic and transonic flow regime have been conducted for the Stability and Control Configuration (SACCON), which has a leading edge sweep of 53°, to assess the control surface effectiveness of conventional trailing-edge control devices. The present study reviews the experimental investigations conducted with the highly swept generic UCAV configuration SACCON.