16885J/ESD35J-oct1,2002 Competing needs Subsonic mach number High Aspect Ratio for low induced drag Supersonic mach number Want high sweep for subsonic leading edge Possible solutions Variable sweep wing -B-1 Double delta- US SST Blended-Concorde Optimize for supersonic -B-58
16.885J/ESD.35J - Oct 1, 2002 Competing Needs • Subsonic Mach number – High Aspect Ratio for low induced drag • Supersonic Mach number – Want high sweep for subsonic leading edge • Possible solutions – Variable sweep wing - B-1 – Double delta - US SST – Blended - Concorde – Optimize for supersonic - B-58
16885J/ESD35J-oct1,2002 Supercritical airfoil Supercritical airfoil shape keer ps uppe surface velocity p, cI from getting too arge Uses aft camber to generate lift Gives nose down pitching moment
16.885J/ESD.35J - Oct 1, 2002 Supercritical Airfoil Supercritical airfoil shape keeps upper surface velocity from getting too large. Uses aft camber to generate lift. Gives nose down pitching moment. Cp x/c Cp, cr V 8