Boeing N+2 Supersonic Experimental Validation Phase II Program

Phase II of a two-phase study is described that designs and validates a supersonic airliner feasible for entry into service in the 2018 to 2020 timeframe (NASA N+2 generation). A Mach 1.6 to 1.8 low sonic-boom aircraft configuration is further developed with special emphasis on propulsion integration and its effect on sonic-boom and performance goals. An over-wing inlet, nacelle installation, and nozzle are designed to meet aggressive sonic-boom and performance goals using CFD-based shape optimization. The concept and the tools utilized for its design are validated through a series of wind-tunnel tests at the NASA Ames 9 ft x 7 ft Supersonic Wind Tunnel and NASA Glenn 8 ft x 6 ft Supersonic Wind Tunnel. Comparisons between CFD and wind-tunnel near-field pressure distributions and inlet mass flow, pressure recovery, and distortion data are made. Results show the over-wing inlet concept has good performance and minimal impact on the sonic-boom signature.