Characteristics of the N. A. C. A. 23012 Airfoil From Tests in the Full-Scale and Variable-Density Tunnels

This report gives the results of tests in the N. A. C. A. full-scale and variable-density tunnels of a new wing section, the N. A. C. A. 23012, which is one of the more promising of an extended series of related airfoils recently developed. The tests were made at several values of the Reynolds Number between 1,000,000 and 8,000,000. The new airfoil develops a reasonably high maximum lift and a low profile drag, which results in an unusually high value of the speed-range index. In addition, the pitching-moment coefficient is very small. The superiority of the new section over well-known and commonly used sections of small camber and moderate thickness is indicated by making a direct comparison with variable-density tests of the N. A. C. A. 2212, the well-known N. A. C. A. family airfoil, that most nearly resembles it. The superiority is further indicated by comparing the characteristics with those obtained from full-scale-tunnel tests of the Clark Y airfoil.

A comparison is made between the results for the newly developed airfoil from tests in the N.A. C. A. variable-density and full-scale wind tunnels. When the results from the two tests are interpreted on the basis of an "effective Reynolds Number" to allow for the effects of turbulence, reasonably satisfactory agreement is obtained.