Abstract
A fully reusable rocket vehicle is proposed to demonstrate good operability characteristics both on the ground and in flight. For achieving technical readiness for future space transportation systems, design considerations not only for higher performance-related issues but also those for good operability are needed The proposed vehicle is to be used as a sounding rocket and has the capabilities of ballistic flight returning to the launch site, and landing vertically making use of clustered liquid hydrogen rocket engines. Before initiating the development of this type of reusable rocket, a small test vehicle with a liquid hydrogen rocket engine was built and flight tested. A demonstration of vertical landing and exercise of turnaround operation for repeated flights are the major objectives of the test vehicle. Two series of flight tests were performed in 1999 and 2001 and the flight test operation provided repeated flight environment and many lessons valuable for designing the fully reusable rocket vehicle.
