本文论证了高M_α数亚燃冲压发动机用于航天飞机的可能性。并对用液氢、甲烷、丙烷等作为燃料的冲压发动机特性作了详细的计算分析。讨论了冲压发动机的工作菱形区、发动机特性及各截面的协调关系等问题。计算结果表明,在M_α=2～6及H=0～40km范围内,亚燃冲压发动机能满足航天飞机对动力装置的要求。在一定的条件下,液氢、甲烷和丙烷均可以被选为航天飞机用的冲压发动机的燃料。 This article demonstrates the possibility of a high M_α number sub-ramjet used in a space shuttle. The characteristics of ramjet engine using liquid hydrogen, methane, propane as fuel were calculated and analyzed in detail. The working diamond area of ​​the ramjet engine, the engine characteristics and the coordination relationship among the cross sections are discussed. The calculation results show that in the range of M_α = 2 ~ 6 and H = 0 ~ 40km, the submarine ramjet engine can meet the requirements of the spacecraft for the power plant. Under certain conditions, liquid hydrogen, methane and propane can all be selected as fuel for ramjet engines for space shuttles.