The effects of equal-pressure fixed slots on the characteristics of a Clark Y Airfoil
This is a 1934 NASA technical report, published by the National Advisory Committee for Aeronautics, presenting wind-tunnel test results on how equal-pressure fixed slots change the lift and drag of a Clark Y airfoil wing section for aircraft designers. The pictures are rotated line graphs of lift coefficient against drag and angle of attack, with dashed and solid curves compared side by side, plus a small wing-section sketch showing slot placement; a designer might borrow the clean plotting conventions and the simple cross-section diagram as a restrained engineering graphic style.
