Air Breathing Rocket Engines and Sustainable Launch Systems

Abstract

An air-breathing rocket engine inhales oxygen from the air for about half the flight, so it doesn't have to store the gas onboard. So at take-off, an air-breathing rocket weighs much less than a conventional rocket, which carries all of its fuel and oxygen onboard. Air breathing rockets, combine the performance characteristics of both rocket and ramjet engines. An air-breathing engine gets its initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn the hydrogen fuel. Once the vehicle's speed increases to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the vehicle into orbit. And therefore reducing a vehicle's weight decreases cost significantly. And since an air breathing engine cannot get required initial take off thrust, various launch types like air augmented rockets, horizontal launch mode courtesy hybrid engine, magnetic levitation launch systems are used for initial thrust requirements ,thus reducing fuel emissions and increases net efficiency of rockets. Hence air breathing engines can be implemented to address energy considerations and reduce costs.