I was doing a study on airfoils shape for a rocket. I tested the diamond and the hexagonal airfoil with Missile DatCom, RasAero and the Shock Expansion theory and from my results it seems like the diamond is better (little more lift and noticeable less drag). Looking at other rockets design I found out that many actually uses hex airfoil, but I don't get why. Am I missing something? Any reason for that?
Also like 99% of rocket uses a sweep angle. If I remember correctly, having a sweep angle reduces the Mach number normal to the L.E., so using a sweep angle means that I'll have a subsonic flow normal to the L.E. even if the fligh Mach is supersonic. So, the L.E. should be rounded. Since all these rockets uses thin sharp airfoils, wouldn't the wing work better with no sweep angle?