Abstract: A rotor for a turbofan booster section associated with a fan section of a gas turbine engine includes a rotor blade having an airfoil extending in a spanwise direction from 0% span at a root to 100% span at a tip and having a leading edge and a trailing edge. The airfoil has a plurality of spanwise locations between the root and the tip each having a normalized local maximum thickness. A value of the normalized local maximum thickness decreases from the root to a minimum value and increases from the minimum value to the tip, and the minimum value is within 60% span to 90% span. The rotor includes a rotor disk coupled to the rotor blade configured to be coupled to a shaft or a fan to rotate with the shaft or the fan, respectively, at the same speed as the shaft and the fan.