Propulsion systems selected for commercial transports must provide efficient and reliable performance over a broad range of conditions. These aeroplanes are used over both short and long route segments, on non-standard days, and at a range of altitudes to meet air-line schedule requirements.

This paper covers some of the design parameters that were considered in the integration of the induction system, secondary air system, jet nozzle and the basic turbojet gas generator for the SST. During recent years some of the most important gains in propulsion efficiency have resulted from the development of inlets, engines and exhaust nozzles which are matched over a broad range of operating conditions. An efficient propulsion system for a supersonic transport depends upon very close matching of these components. This, of course, requires a better understanding of the capabilities and limitations of each of these major components. For the supersonic transport, 50% or more of the gross weight will be comprised of propulsion system and fuel and less than 10% will be payload.