Recent Status of Experimental Subscale Winged Rocket WIRES#015 and its Full Expander Cycle LOX/LNG Engine Combustion Test

Space Systems Laboratory at Tokyo University of Science and Tokyo University of Science's start-up SPACE WALKER Inc. have been developing an experimental subscale winged rocket called WIRES#015 (WInged REusable Sounding rocket) in cooperation with Japan Aerospace Exploration Agency (JAXA). It has the dimensions of 4.6m and initial mass of 1, 000kg to conduct the comprehensive flight demonstration of the technologies for realizing suborbital spaceplane such as LOX/LNG (Liquid OXygen/Liquefied Natural Gas) engine, autonomous flight technology (Navigation, Guidance and Control) and full composite LOX/LNG propellant tanks. The LOX/LNG engine of 16kN vacuum thrust has a full expander cycle system with a common pump to feed LOX and LNG propellant to the combustor, which achieves Isp (specific impulse) of 224s. The features of NGC are the real time guidance by DynDGA (Dynamic Distributed Genetic Algorithm) and the attitude control law by DI (Dynamic Inversion) theory that guarantees stability onboard. One of the most important demonstration technologies is the world's first composite liquid oxygen tank using LOX compatible pCFRTP (pitch Carbon Fiber Reinforced Thermo-Plastic Resin), which is currently being a joint research and development with DLR. WIRES#015 is currently in the process of fabrication. The helicopter drop test using dummy vehicle for validating the recovery system will be conducted in February 2024, and the helicopter sling test of WIRES#015 for validating the NGC will be performed in May 2024. The hardware-in-the-simulation test are scheduled for mid-2025. The LOX/LNG engine test has been conducted in March 2023. The CFT (Captive Firing Test) will be scheduled in January 2025. The first flight test of WIRES#015 will be conducted in December 2025 followed by the three additional flight tests.