Prediction and evaluation of the stage-separation compatibility of an internally carried air-launch vehicle

This work mainly predicts and evaluates the stage-separation compatibility of an internally carried air-launch vehicle by a multi-body separation wind-tunnel free-flight (WTFF) test without restraining the motional freedom. The Mach number is Ma=1.5, and the initial-launch angle of attack is considered to be α₀=0° and α₀=3°. The result shows that WTFF test is a feasible prediction and evaluation method for the stage-separation compatibility of an ICAL vehicle when the combined vehicle exhibits static stability. The launch-vehicle can be separated safely from the carrier-aircraft and has a good pitch-angle for ignition when α₀=0°. However, the launch-vehicle exhibits a large pitch-angle when it separates completely from the carrier-aircraft when α₀=3°, which is unacceptable. Different separation velocities have little influence on the stage-separation compatibility of the ICAL vehicle when α₀=3°. The stage-separation compatibility of the ICAL vehicle is first investigated by a free-flight technique in a wind-tunnel, which provides a new research idea for interdisciplinary studies of the kinematics and aerodynamics of multi-body systems.