Post Flight Aerodynamic Analysis of the Experimental Vehicle PRORA USV 1

Abstract

Some results of the post flight analysis of the aerodynamic experiment carried out within the frame of USV project, the first Space experimental vehicle funded by the Italian National Aerospace Research Program (PRORA), are shown in this paper. The first mission DTFT (Dropped Transonic Flight Test) of the Unmanned Space Vehicle 1 (USV1) developed at CIRA, was performed at the end of February 2007, and it was aimed at experimenting the transonic flight of a re-entry vehicle. USV is basically composed by a Flying Test Bed (FTB1) and a Carrier based on a stratospheric balloon. The FTB1 is a slender, not-propelled, winged vehicle able to perform experiments on Aerodynamics, Structure and Materials, Autonomous Guidance Navigation and Control. The logical path of the USV aerodynamic experiment entails the comparison between Pre-Flight prediction and In-Flight measurements. Such comparison will be actuated by means of the acquisition during the USV flight both of the global aerodynamic coefficients (inertial measurements) and local quantities (pressure measurements). During the flight, static pressure measurements over the vehicle surface are gathered. 304 probe have been located in the most interesting regions of the vehicle. Some selected flight conditions occurred during the DTFT mission of the FTB1 vehicle have been numerically rebuilt, the attention being focused to the surface pressure distributions to be compared with in-flight pressure measurements. After the execution of these CFD simulations, results have been critically analyzed and compared to flight data. All the information deriving from the Aerodynamic Flight Experiment will be finally used to improve the existing Aerodynamic Prediction Model.