Wind-tunnel Investigation of the NACA 654-421 Airfoil Section with a Double Slotted Flap and Boundary Layer Control by Suction
A 1947 NACA technical note from NASA's Technical Reports Server reporting wind-tunnel tests of a 654-421 airfoil section with a double slotted flap and suction boundary-layer control, aimed at aeronautical engineers. The pages are charts of section lift coefficient plotted against angle of attack, and drag coefficient plotted against lift, with curves for smooth and rough conditions and flap retracted or extended. A designer might borrow the clean grid-plot layout, the labelled curve families and the restrained two-tone print look.
