The U.S.A.-27-D modified airfoil was tested at M.I.T. during September, 1921, to determine lift, drag, L/D, and moments about the leading edge. The test was run at a wind velocity of 30 miles per hour. The results of the test on this airfoil are compared with results of tests on the original U.S.A.-27-C, the U.S.A.-27, and the Dayton-Wright Gottingen No. 387.