US Patent 9140127 Gas turbine engine airfoil

An airfoil of a turbine engine includes pressure and suction sides that extend in a radial direction from a 0% span position at an inner flow path location to a 100% span position at an airfoil tip. The airfoil has a relationship between a tangential stacking offset and a span position that is at least a third order polynomial curve that includes at least one positive and negative slope. The positive slope leans toward the suction side and the negative slope leans toward the pressure side. An initial slope starting at the 0% span position is either zero or positive. The first critical point is in the range of 5-15% span.