Rotor/wing dual mode hub fairing system

• US 7,434,763 B2
• Filed: 09/28/2005
• Issued: 10/14/2008
• Est. Priority Date: 09/28/2005
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Walliser, Eric W., Nowak, Robert A.
• Primary Examiner(s): DINH, TIEN QUANG
• Application Number:
  US11/162,924
• Publication Number:
  US 20080149759A1
• Time in Patent Office: 1,112 Days
• Field of Search: 244/6, 244/7.R, 244/7.A, 244/17.11, 244/17.27, 244/8, 244/12.4, 244/17.25, 416/142, 416/143
• US Class Current: 244/7.00R
• CPC Class Codes: B64C 27/24 with rotor blades fixed in flight to act as lifting surfaces
• CPC Class Codes: B64C 27/30 with provision for reducing drag of inoperative rotor

Abstract

A hub fairing system (12) for a stopped-rotor aircraft (10) having a fuselage (14) including a hub (16). The hub (16) is mechanically coupled to the fuselage (14) and to multiple blades (40) and is rotated by an engine (22). A retractable fairing (60, 64) covers a portion of the hub (16). An actuator (26) is coupled to the fairing (60, 64). A controller (28) is coupled to the actuator (26) and retracts the fairing (60, 64). A method of reducing drag on the aircraft includes transitioning between a rotary-wing mode and a fixed-wing mode. The fairing (60, 64) is deployed over a portion of the hub (16) upon the completion of the transition between flight modes.

Claims

1. A hub fairing system for an aircraft having a fuselage and a rotor that is rotatable relative to the fuselage in a rotary-wing mode of operation and is fixed relative to the fuselage in a fixed-wing mode of operation, said hub fairing system comprising:

a hub mechanically coupled to said rotor and rotatable relative to said fuselage and is in a vertically fixed position with respect to the fuselage;

a first fairing disposed forward of said hub that is movable between a deployed position and a retracted position, said first fairing having an edge that is disposed near to said rotor in said deployed position and further away from said rotor in said retracted position, and said first fairing in said deployed position covering a portion of said hub disposed between said rotor and said fuselage;

a controller for controlling the position of said first fairing; and

a first actuator mechanically coupled to said first fairing for moving said first fairing between said deployed and retracted positions in response to command signals from said controller.

2. The system as recited in claim 1, wherein said first fairing has an external surface that forms a continuous aerodynamic surface extending from said fuselage toward said rotor in said deployed position of said first fairing.

3. The system as recited in claim 1, further comprising:

a second fairing that is movable between a deployed position and a retracted position, said second fairing having an edge that is disposed near said rotor in said deployed position and further away from said rotor in said retracted position; and

a second actuator mechanically coupled to said second fairing for moving said second fairing between said deployed and retracted positions in response to command signals from said controller for controlling the position of said second fairing.

4. The system as recited in claim 3, and said second fairing is disposed aft of said hub.

5. The system as recited in claim 3, further comprising a fixed fairing that is fixed to said rotor, said first, second and fixed fairings forming a drag-reducing surface when said first and second fairings are in their respective deployed positions.

6. The system as recited in claim 1, further comprising a fixed fairing that is fixed to said rotor, said first and fixed fairings forming a drag-reducing surface when said first fairing is in said deployed position.

7. The system as recited in claim 6, wherein portions of fixed second fairing extend in cantilever fashion forward and aft of said rotor respectively.

8. The system as recited in claim 6, further comprising an element for coupling said first fairing to said fixed fairing when said first fairing is in its deployed position during said fixed-wing mode of operation.

9. The system as recited in claim 1, wherein said rotor comprises a plurality of blades.

10. The system as recited in claim 1, wherein said first fairing in said retracted position is stowed within an outer mold line of said fuselage.

11. The system as recited in claim 1, further comprising a set of hinges, said first fairing pivoting on said set of hinges during movement between its deployed and retracted positions.

12. The system as recited in claim 1, further comprising an element for coupling said first fairing to said rotor when said first fairing is in its deployed position during said fixed-wing mode of operation.

13. The system as recited in claim 12, wherein said coupling element is activated in response to a command signal from said controller.

14. The system as recited in claim 1, wherein said first fairing in said retracted position extends around a propulsion component.

15. The system as recited in claim 1, wherein said first fairing in said retracted position shields a portion of said hub lying below a swashplate from outside air turbulence.

16. A hub fairing system for an aircraft having a fuselage and a rotor that is rotatable relative to the fuselage in a rotary-wing mode of operation and is fixed relative to the fuselage in a fixed-wing mode of operation, said hub fairing system comprising:

a hub mechanically coupled to said rotor and rotatable relative to said fuselage and is in a vertically fixed position with respect to the fuselage;

a first fairing that is movable between a deployed position and a retracted position, said first fairing disposed forward of said hub having an edge that is disposed near to said rotor in said deployed position and further away from said rotor in said retracted position, and said first fairing in said deployed position covering a forward portion of said hub disposed between said rotor and said fuselage;

a second fairing that is movable between a deployed position and a retracted position, said second fairing having an edge that is disposed near said rotor in said deployed position and further away from said rotor in said retracted position, and said second fairing in said deployed position covering an aft portion of said hub disposed between said rotor and said fuselage;

a controller for controlling the positions of said first and second fairings;

a first actuator mechanically coupled to said first fairing for moving said first fairing between said deployed and retracted positions in response to first command signals from said controller; and

a second actuator mechanically coupled to said second fairing for moving said second fairing between said deployed and retracted positions in response to second command signals from said controller,

wherein said controller is programmed to send said first and second command signals before the aircraft can be operated said fixed-wing mode.

17. The system as recited in claim 16, further comprising a third fairing that is fixed to said rotor, said first, second and third fairings forming a drag-reducing surface when said first and second fairings are in their respective deployed positions.

18. The system as recited in claim 17, wherein said first fairing has an external surface that forms a continuous aerodynamic surface extending from said fuselage to said third fairing in said deployed position of said first fairing, and said second fairing has an external surface that forms a continuous aerodynamic surface extending from said fuselage to said third fairing in said deployed position of said second fairing.

19. The system as recited in claim 16, further comprising first and second sets of hinges, said first fairing pivoting on said first set of hinges during movement between its respective deployed and retracted positions, and said second fairing pivoting on said second set of hinges during movement between its respective deployed and retracted positions.