S4233

• S4233-PT (Fig. 12.101)

• S4233-PT u. s.t. xjc — 20%, hjc = .17%,w/c= 1.0% (Fig. 12.102)

The S4233 was designed to be an improvement over the MB253515. To date the S4233 has probably been most used by Bob Champine, retired NACA/NASA test pilot, who recently achieved his second LSF level 5 flying his “stretched” GEMINI with the S4233. His enthusiasm for this airfoil is reflected in the accuracy of the wind tunnel model which he built.

Note that the 13.6% thick S4233 has a wider lift range and lower drag than the 15% thick MB253515. As with the MB253515, the S4233 shows a bulge in the drag at a Rn of 100k, so one would expect a trip to improve matters. Fig. 12.102 shows that the low-Rn drag can indeed be reduced using a trip, but the performance with the trip is slightly worse at Rn of 300k.

Also see: MB253515, E193MOD, WB135/35, SD7062 Digitizer plot: Fig. 10.38 Polar plot: Figs. 12.101, 12.102 Lift plot: Fig. 12.103

Thickness: 13.64% Camber: 3.26%