The 1959 hypersonic aircraft concepts by A. J. Eggers Jr. of NASA and Wallace D. Hayes of Princeton University.

ARROW WINGED hypersonic aircraft above are suggestions of A. J. Eggers, Jr. of NASA and Wallace D. Hayes of Princeton University. The flat topped Eggers' configuration (middle), is designed to benefit from flow interference effects. Hayes aircraft (right) with the flat bottom is intended to keep skin friction drag low. Flight test information probably will be required to prove which design idea is best for any given speed and altitude situation. Slender high performance, high lift/drag ratio shapes of this type arc best suited for flights half-way around the world down to trans-continental ranges. Blunt shapes are better for global ranges.