 flow sonic stream airfoil surfac flow sonic stream airfoil surfac studi flow airfoil near-sonic stream indic factor determin pressur distribut airfoil analysi mach wave pattern suggest superson domain flow deriv simpl-wave flow aris mach wave reflect sonic chang airfoil surfac slope compress reflect mach wave determin quantit function airfoil lead-edg geometri analysi measur pressur distribut uncamb airfoil superimpos wave system curv surfac equival simpl-wave flow airfoil applic scheme calcul pressur distribut airfoil sonic stream good agreement experi 