An apparatus comprising: a gas turbine engine component having a plurality of fixed airfoil members (60, 62) distributed circumferentially about a reference axis; a plurality of movable airfoil extensions structured for use in a flow path of a gas turbine engine and positioned intermediate a first one of the plurality of fixed airfoil members and a second one of the plurality of fixed airfoil members, each of the plurality of movable airfoil extensions configured to be moved between a first operating position adjacent a first one of the plurality of fixed airfoil members and a second operating position adjacent a second fixed airfoil member, wherein at transition positions intermediate the first operating position and the second operating position the plurality of movable airfoil extensions are free of interfacing contact with the first and second one of plurality of airfoil members (60, 62); wherein movement of the plurality of movable airfoil extensions between the first operating position and the second operating position alters a flow path characteristic of both the first one of the plurality of fixed airfoil members and the second one of the plurality of fixed airfoil members, characterized in that (i) the plurality of fixed airfoil members (60, 62) include cooling apertures that are exposed in the first operating position and covered in the second operating position and/or (ii) the plurality of airfoil extensions include cooling holes through which a cooling fluid can exit during operation of the movable airfoil extensions that are exposed in the first operating position and closed in the second operating position. a gas turbine engine component having a plurality of fixed airfoil members (60, 62) distributed circumferentially about a reference axis; a plurality of movable airfoil extensions structured for use in a flow path of a gas turbine engine and positioned intermediate a first one of the plurality of fixed airfoil members and a second one of the plurality of fixed airfoil members, each of the plurality of movable airfoil extensions configured to be moved between a first operating position adjacent a first one of the plurality of fixed airfoil members and a second operating position adjacent a second fixed airfoil member, wherein at transition positions intermediate the first operating position and the second operating position the plurality of movable airfoil extensions are free of interfacing contact with the first and second one of plurality of airfoil members (60, 62); wherein movement of the plurality of movable airfoil extensions between the first operating position and the second operating position alters a flow path characteristic of both the first one of the plurality of fixed airfoil members and the second one of the plurality of fixed airfoil members, characterized in that (i) the plurality of fixed airfoil members (60, 62) include cooling apertures that are exposed in the first operating position and covered in the second operating position and/or (ii) the plurality of airfoil extensions include cooling holes through which a cooling fluid can exit during operation of the movable airfoil extensions that are exposed in the first operating position and closed in the second operating position. (i) the plurality of fixed airfoil members (60, 62) include cooling apertures that are exposed in the first operating position and covered in the second operating position and/or (ii) the plurality of airfoil extensions include cooling holes through which a cooling fluid can exit during operation of the movable airfoil extensions that are exposed in the first operating position and closed in the second operating position.