Combined Engine for Reusable Launch Vehicle (KLIN Cycle)

Predicted performance and features of a combinedpropulsion concept for a small reusable launchvehicle known as KLINTM (meaning wedge in Russian) Cycle are discussed. The KLIN Cycle consists of a thermally integrated deeply cooled turbojet and a liquid rocket engine. The objective of this concept is to achieve a high-pressure ratio in a simple, lightweight turbojet engine. The proven result is an exceptional engine thrust-to-weight ratio, as well as improved speciŽ c impulse and mass fraction of the launcher. When based on the RL10 engine family, the KLIN Cycle makes a small single-stage-to-orbit and two-stage-to-orbit reusable launch vehicles feasible and very economically attractive.