Airfoil having a spline fillet

An airfoil for a gas turbine engine, which has an airfoil body extending in a spanwise direction and in a chordwise direction, a platform located at an inner end and/or an outer end of the airfoil body, and a fillet at a junction between the airfoil body and the platform. The fillet has a radius distribution at a given chordwise location, the radius distribution varying from the platform to the airfoil body in the spanwise direction. The radius distribution defines a local minimum, the radius of the fillet at the given chordwise location increasing from the local minimum along the spanwise direction toward both of the airfoil and the platform. A local maximum of the radius distribution is offset from the local minimum along the spanwise direction, the radius decreasing from the local maximum along the spanwise direction toward both of the airfoil and the platform.