An airfoil family for a helicopter rotor blade, designated SC362XX. SC362XX essentially removes the large lower surface suction peak associated with ‘drag creep’ at moderate lift coefficients while reducing the peak Mach number and shock strength at high lift/Mach number conditions. Another optional airfoil family for use at inboard regions of the helicopter rotor, which is designated SC3252XX airfoil family, is a relatively thicker airfoil section that includes a significant increase in thickness forward of the 30% x/c location to provide a relatively thick and rigid inboard section. The lift coefficient at which the drag divergence Mach number was optimized is the same in both families thereby readily providing application to a single rotor blade.