HSCT inlet development issues

The purpose of this presentation is to highlight the issues affecting the development of engine air inlets for the HSCT. The Propulsion Airframe Integration Technology (PAIT) contract sponsored by NASA LeRC is an important element in the evolution of the propulsion system that will eventually power the HSCT. Most of the material presented here is based on work performed by The Boeing Company under Task 1 and 2 of PAIT. From the propulsion perspective, the premier technology issues associated with the HSCT are airport noise and high altitude emissions. The sources are the nozzle and combustor, respectively. For the inlet the most challenging issues are associated with integration. Among the issues are the following: integration with the main landing gear--protection from FOD and water and slush ingestion from the runway; integration with the engine--ensuring engine/inlet airflow matching, normal shock stability during engine airflow transients, and keeping total pressure distortion within acceptable limits; integration with the wing--minimizing nacelle/wing interference drag and inlet flowfield velocity distortion.