Some recent innovations in wind tunnel testing techniques. Paper presented at the National Aeronautic and Space Engineering and Manufacturing Meeting, Los Angeles, California, October 6-10, 1969.

In recent years, several innovations have been made in wind tunnel testing techniques which have significantly improved the testing cost effectiveness. Use of colored water spray in low speed testing causes unsuspected vortices to stand out allowing quick and accurate drag reduction filleting to be prepared. Simultaneous force and pressure model transonic testing has reduced the time and cost to arrive at a low drag airplane configuration by more than 50%.