"An investigation has been conducted in the Langley 4- by 4-foot supersonic tunnel to determine the static lateral stability characteristics of a supersonic aircraft configuration at Mach numbers of 1.40 and 1.59. The model had a 40 degree sweptback wing with 10-percent-thick circular-arc sections normal to the quarter-chord line. The results of the investigation indicated high directional stability that decreased with increasing Mach number and positive effective dihedral that was essentially invariant with lift coefficient and Mach number" (p. 1).