A stator assembly for an aircraft engine, has: vanes distributed about a central axis, a vane having: an airfoil extending from a first end to a second end along a span and from a leading edge to a trailing edge along a chord, the airfoil having a pressure side and a suction side opposed to the pressure side; a slot within the airfoil, the slot extending in a direction having a component along the chord, the slot located between the pressure side and the suction side; a port at the leading edge, the port fluidly communicating with the slot and with the gaspath; a mass located within the slot, the mass movable within the slot to shift a center of gravity of the vane in a chordwise direction; and a biasing member biasing the mass in a direction opposite a pressure force generated by the flow of fluid.