ExoMars Flush Air Data System: Entry Simulation and Atmospheric Reconstruction Method

Flight data recorded during atmospheric entry with forebody pressure instrumentation, referred to as a flush air data system (FADS), provide valuable measurements for the reconstruction of the trajectory and in situ atmospheric conditions. We present a method to reconstruct the angle of attack; sideslip angle; and atmospheric density, pressure, and temperature in support of the postflight analysis for the ExoMars Entry, Descent, and Landing Demonstrator Module (EDM), named Schiaparelli. Numerical predictions of the forebody surface pressure distribution, required as input to the FADS reconstruction, were developed in a companion paper. Here, we demonstrate the FADS method in a hypersonic wind tunnel at Mach 5 to 7 and study theoretical FADS reconstruction performance along a simulated along a simulated entry trajectory. The main error sources identified are unobserved winds and measurement bias errors; the latter are exacerbated by the limited number of pressure ports on the EDM.