[1] This shape is in contrast to subsonic airfoils, which often have rounded leading edges to reduce flow separation over a wide range of angle of attack.
[2] A rounded edge would behave as a blunt body in supersonic flight and thus would form a bow shock, which greatly increases wave drag.
The airfoils' thickness, camber, and angle of attack are varied to achieve a design that will cause a slight deviation in the direction of the surrounding airflow.
Years of research and experience with the unusual conditions of supersonic flow have led to some interesting conclusions about airfoil design.
Aerodynamic efficiency for supersonic aircraft increases with thin section airfoils with sharp leading and trailing edges.