Abstract: A rotor blade configured to be installed on a rotary wing aircraft includes a spar including an inboard portion extending from a root of the rotor blade to a first spanwise position of the rotor blade and an outboard portion meeting the inboard portion at the first spanwise position. The rotor blade further includes an upper skin and a lower skin coupled the outboard portion of the spar. The first spanwise position is defined by a most inboard point at which the upper and lower skins are coupled to the spar. The inboard portion includes a top layer, a bottom layer, and an inner cavity. The top layer has a substantially constant first thickness and the bottom layer has a substantially constant second thickness, and the distance between an outer surface of the top layer and an outer surface of the bottom layer is substantially constant.

Abstract: A method of modifying a rotor blade is provided for a rotor blade including a spar having an inboard portion with a substantially constant overall height, the inboard portion further including a top layer having a substantially constant first thickness and a bottom layer having a substantially constant second thickness. The method includes removing a root portion of the inboard portion to thereby modify the rotor blade and installing a cuff configured to couple to the rotor blade to an aircraft.

Abstract: A rotor blade for a rotary wing aircraft includes a leading edge and a trailing edge defining a chordwise direction. The leading edge defines a forward end of the rotor blade and the trailing edge defines an aft end of the rotor blade. The rotor blade has a center of gravity and an aerodynamic center along the chordwise direction. The center of gravity is aft of the aerodynamic center.

Abstract: A method of modifying a rotor blade is provided for a rotor blade including a spar having an inboard portion with a substantially constant overall height, the inboard portion further including a top layer having a substantially constant first thickness and a bottom layer having a substantially constant second thickness. The method includes removing a root portion of the inboard portion to thereby modify the rotor blade and installing a cuff configured to couple to the rotor blade to an aircraft.

Abstract: A tail rotor blade for a helicopter includes a blade body defining a longitudinally extending spar cavity, a leading edge forward of the spar cavity, and a trailing edge aft of the spar cavity. Upper and lower airfoil surfaces extend from the leading edge to the trailing edge on opposite sides of the spar cavity. The upper and lower airfoil surfaces define between one another a constant airfoil segment and transition airfoil segments disposed longitudinally adjacent to the constant airfoil segment on inboard and outboard sides of the constant airfoil segment.

Abstract: A composite piece tool used to create a composite piece. The tool includes a substrate having a substrate surface, walls disposed on the substrate and extending from the substrate surface in a thickness direction of the composite piece to define opposite locations of longitudinal composite piece ends and composite piece sides, a tooling surface disposed to occupy an entirety of a space delimited by the walls and on which the composite piece formed and a servo controller coupled to the tooling surface and configured to move the tooling surface upwardly and downwardly relative to the substrate surface and walls to form the composite piece.

Abstract: A blade element is provided and includes courses of bias plies continuously machine-wrapped about leading and trailing edges at an angle relative to a long axis of the blade axis and unidirectional plies interwoven in parallel with the long axis between adjacent courses of the bias plies on upper and lower surfaces to promote respective tangential geometries of the bias plies at the leading and trailing edges, the unidirectional plies not extending into the leading and trailing edges.

Abstract: A tail rotor blade for a helicopter includes a blade body defining a longitudinally extending spar cavity, a leading edge forward of the spar cavity, and a trailing edge aft of the spar cavity. Upper and lower airfoil surfaces extend from the leading edge to the trailing edge on opposite sides of the spar cavity. The upper and lower airfoil surfaces define between one another a constant airfoil segment and transition airfoil segments disposed longitudinally adjacent to the constant airfoil segment on inboard and outboard sides of the constant airfoil segment.

Abstract: A composite piece tool used to create a composite piece. The tool includes a substrate having a substrate surface, walls disposed on the substrate and extending from the substrate surface in a thickness direction of the composite piece to define opposite locations of longitudinal composite piece ends and composite piece sides, a tooling surface disposed to occupy an entirety of a space delimited by the walls and on which the composite piece formed and a servo controller coupled to the tooling surface and configured to move the tooling surface upwardly and downwardly relative to the substrate surface and walls to form the composite piece.

Abstract: A blade element is provided and includes courses of bias plies continuously machine-wrapped about leading and trailing edges at an angle relative to a long axis of the blade axis and unidirectional plies interwoven in parallel with the long axis between adjacent courses of the bias plies on upper and lower surfaces to promote respective tangential geometries of the bias plies at the leading and trailing edges, the unidirectional plies not extending into the leading and trailing edges.