Simulation analysis of the hope-X demonstrator

A high-speed flight demonstration program using scale models is planned as part of NAL/NASDA joint research for the HOPE-X unmanned re-entry vehicle project. The program consists of two phases, and the objective of Phase II is to reduce the uncertainties in the HOPE-X transonic aerodynamic data, which are greater than those of other speed regions. The experimental method for Phase II is highly unique: the experiment vehicle is to be launched from a stratospheric balloon and accelerate in free fall. During the data acquisition phase, the vehicle will fly at a constant Mach number while changing its angle of attack quasi-statically. The vehicle’s trimmed aerodynamic characteristics will then be estimated from the flight data. In this paper, flight profiles for the experiment are investigated using mathematical simulation. The results show that flight at constant Mach number with angle of attack sweeps can- be achieved by the proposed experiment method.