Thermoplastic composite panel with corrugated peaks and troughs stiffening systems and methods

1 . A method for forming a fiber-reinforced thermoplastic control surface, comprising:

stacking plies of thermoplastic composite sheets to a first desired thickness to form a first skin;

stacking plies of thermoplastic composite sheets to a second desired thickness to form a second skin;

forming the first skin in a first contour;

forming the second skin in a second contour;

forming a stiffening member including a thermoplastic resin, the stiffening member including a cross-sectional shape having a plurality of peaks and troughs, the cross-sectional shape defining a sinusoidal wave with a varying amplitude;

assembling the stiffening member between the first skin and the second skin; and

joining the stiffening member to the first skin and the second skin.

2 . The method of claim 1 , wherein forming the first skin, forming the second skin, and forming the stiffening member are each performed via stamp forming.

3 . The method of claim 1 , wherein forming the first skin, forming the second skin, and forming the stiffening member are each performed via twin sheet forming.

4 . The method of claim 1 , wherein forming the first skin, forming the second skin, and forming the stiffening member are each performed via automated fiber placement.

5 . The method of claim 1 , wherein the plurality of peaks are joined to and mate with the first skin, and wherein the plurality of troughs mate with and are joined to the second skin.

6 . The method of claim 1 , wherein an outer surface of the first skin defines a structure of an aircraft component.

7 . The method of claim 1 , wherein the first skin includes an outer surface that defines a control surface, and the second skin includes an inner surface at least partially defining a hollow chamber of an airfoil.

8 . A method for forming a fiber-reinforced thermoplastic control surface, comprising:

forming a combined first skin and first stiffening member by joining a first skin to a plurality of peaks of the first stiffening member;

forming a combined second skin and second stiffening member by joining a second skin to a plurality of troughs of the second stiffening member;

bonding the combined first skin and the first stiffening member to the combined second skin and the second stiffening member; and

in response to bonding the combined first skin and the first stiffening member to the combined second skin and the second stiffening member, forming a stiffening member of the fiber-reinforced thermoplastic control surface, the stiffening member comprising a cross-secitonal shape defining a sinusoidal wave with a varying amplitude.

9 . The method of claim 8 , wherein joining the combined first skin and stiffening member and the combined second skin and the second stiffening member includes joining the first stiffening member to the second stiffening member, and wherein the first stiffening member and the second stiffening member are joining along a contour of the first stiffening member and the second stiffening member.

10 . The method of claim 8 , wherein forming the combined first skin and the first stiffening member and forming the combined second skin and the second stiffening member each comprise stamp forming.

11 . The method of claim 8 , wherein forming the combined first skin and the first stiffening member and forming the combined second skin and the second stiffening member each comprise twin sheet forming.

12 . The method of claim 8 , wherein forming the combined first skin and the first stiffening member and forming the combined second skin and the second stiffening member each comprise automated fiber placement.

13 . The method of claim 8 , further comprising stacking plies of thermoplastic composite sheets to a first desired thickness to form the first skin and stacking plies of thermoplastic composite sheets to a second desired thickness to form the second skin.

14 . The method of claim 8 , wherein joining includes consolidation and cooling.

15 . The method of claim 8 , wherein joining includes welding.