In-flight aero-optics of turrets

Abstract. Recent in-flight aero-optical measurements from the Airborne Aero-Optics Laboratory are provided, along with instrumentation and experimental set-up. Results of an extensive survey of the aero-optical environment at different viewing angles, for both flat-window and conformal-window turrets at different subsonic and low transonic speeds below M=0.65, are presented, compared and extensively discussed. A comparison between two turret geometries, hemisphere-on-cylinder and hemisphere only, plus the statistical analysis of wavefronts at different viewing angles, are also presented and discussed. Additionally, dynamics of a local shock appearing on the conformal-window turret at transonic Mach number are discussed.