
 Aviation and Aerodynamics: Ludwig Prandtl 
  Direct consequences of the theory were the introduction of the Reynolds number in fluid mechnanics, the effects of the skin friction of fluid flow, many heat transfer problems, the solution of the d'Alembert paradox. 
  Prandtl's other contributions include: the introduction of the Reynolds number in fluid mechanics, airfoils and wing theory (including theories of aerodynamic interference, wingfuselage, wingpropeller, biplane, etc); fundamental studies in the wind tunnel, high speed aerodynamics (correction formula for subsonic compressible flows), theory of turbulence. 
  Prandtl L. Recent progress in the theory of air flow as applied to aeronautics, NACA TM55, 1922. 
 www.aerodyn.org /People/prandtl.html (488 words) 
