Aerothermodynamic Optimization of a TSTO Concept With a Liquid Air Cycle

Regular, routine and affordable access to low Earth orbit (LEO) with heavy payloads is essential to develop infrastructure beyond Earth. A Space Solar Power system based on the Intensified Conversion architecture gives the market parameters to routinely transfer 25000 kg to and from LEO. An initial analysis combines aerodynamics and aerothermodynamics. A hydrogen-oxygen system which collects the oxygen for the rocket phase in flight. The transonic airliner class carrier with hydrogen-fueled turbofans contains the equipment for oxygen collection during subsonic ascent. The second stage starts as transonic ramjet near 18000m, transitions to supersonic combustion at Mach 5 and then to rocket. Aerodynamic lifting surfaces sized by the second stage landing are used in supersonic ascent. This establishes a new basis to estimate launch cost for large-scale infrastructure development in orbit. The optimization results show that a supersonic carrier to Mach 2 and above, along with a higher release altitude for the second stage, should improve payload, but requires design of a completely new supersonic carrier. The results also show the need for oxygen liquefaction systems optimized for LACE and utilizing the availability of liquid hydrogen at the rate needed by the engines.