AIRCRAFT VERTICAL LIFT DEVICE

• US 20110155859A1
• Filed: 12/29/2010
• Published: 06/30/2011
• Est. Priority Date: 12/29/2009
• Status: Active Grant

• Current Assignee: Rolls-Royce North American Technologies, Inc. (Rolls-Royce Holdings Plc)
• Original Assignee: Rolls-Royce North American Technologies, Inc. (Rolls-Royce Holdings Plc)
• Inventors: Barlow, Andrew, Vetters, Daniel Kent
• Granted Patent: US 9,156,549 B2
• Time in Patent Office: Days
• US Class Current: 244/23.A
• CPC Class Codes: B64C 29/0025 the propellers being fixed relative to the fuselage

Abstract

A lift device is disclosed that can be used to provide vertical lift to an aircraft or other vehicle. The lift device can include a fan that produces an airflow and a vane box that can direct the airflow. In one form the fan can be oriented at an angle relative to a reference plane in the aircraft. In another form the vane box can be oriented at an angle. The vane box can be structured to provide a maximum flow area between an aft flow vector and a forward flow vector.

Claims

1. An apparatus comprising:

an aircraft having an engine operable to provide power;

a lift fan powered by the engine and operable to provide a lift for the aircraft along a vertical axis by producing a lift fan flow stream;

a vane assembly fixed relative to the aircraft and positioned downstream of the lift fan and structured to direct the lift fan flow stream in a downward direction, the vane assembly having a plurality of vanes operable to direct the fan flow stream to a vertical vector for hovering flight, a maximum aft vector for forward flight and a maximum forward vector for rearward flight; and

wherein the vane box has a flow area with a maximum at a position other than the vertical vector.

2. The apparatus of claim 1, wherein the lift fan oriented at an angle relative to the vertical axis.

3. The apparatus of claim 2, wherein the angle of the lift fan is the same as the angle of the vane assembly.

4. The apparatus of claim 2, wherein the maximum aft vector is different than the maximum forward vector.

5. The apparatus of claim 2, wherein the aircraft includes an airflow fairing member operable to smooth the flow around a portion of a lift fan housing protruding beyond an airflow surface.

6. The apparatus of claim 1, wherein the plurality of vanes includes a reference angle that is disposed at an angle relative to the vertical axis when the aircraft is in stationary hovering flight.

7. The apparatus of claim 6, wherein the plurality of vanes are aligned in a common plane.

8. The apparatus of claim 1, wherein the vane assembly is disposed within a vane box oriented at an angle relative to the vertical axis, and wherein the maximum flow area of the vane box is between the vertical vector and the maximum aft vector.

9. The apparatus of claim 1, which further includes a diffuser disposed between the lift fan and the vane assembly.

10. An apparatus comprising:

an aircraft including a vertical lift fan having a vector member operable to alter a direction of an exit flow from a shaft driven vertical lift fan, the vector member having a variable discharge flow area and operable to vector a thrust in an aft direction, in a vertical direction, and in a forward direction, a maximum variable discharge flow area of the vector member occurring between the vertical direction and one of the forward direction and aft direction.

11. The apparatus of claim 10, wherein the lift fan is installed at an angle relative to the vertical direction and is operable to produce a flow stream at a non-vertical angle.

12. The apparatus of claim 10, wherein the vertical lift fan is a variable pitch fan.

13. The apparatus of claim 10, which further includes inlet guide vanes disposed upstream of the vertical lift fan.

14. The apparatus of claim 10, wherein the vector member includes a plurality of vanes disposed about a reference axis oriented at an angle relative to the vertical direction.

15. The apparatus of claim 14, wherein the vector member is a vane box having a plurality of variable vanes operable to vary the variable discharge flow area.

16. The apparatus of claim 10, wherein the vector member is oriented at an angle relative to the vertical direction, wherein the vertical lift fan is installed at an angle relative to the vertical direction, and wherein the angle of the vector member is different than the angle of the shaft driven lift fan.

17. The apparatus of claim 10, which further includes a diffuser operable to receive the exit flow and deliver it to the vane assembly.

18. An apparatus comprising:

an aircraft lift fan operable to produce a flow stream to provide vertical lift to an aircraft;

a vane assembly in fluid communication with the aircraft lift fan having a variable flow area and operable to vector the flow stream to a vertical position to produce a hovering of the aircraft, an aft position to produce a forward movement of the aircraft, and a forward position to produce a rearward movement of the aircraft; and

means for locating a maximum flow area of the lift fan at a position between the vertical position and the aft position.

19. A method comprising:

in the construction of an aircraft, installing a vane assembly in fluid communication with a lift fan operable to produce hovering flight for the aircraft, the vane assembly having positions operable to provide forward flight, rearward flight, and hovering flight, the hovering flight position between the forward flight position and the rearward flight position; and

orienting the vane assembly at an angle relative to a reference representative of a horizontal hovering plane of the aircraft, the angle providing a maximum flow area of the vane assembly at a position located on the forward flight side of a hovering flight position.

20. The method of claim 19, which further includes integrating the lift fan with the aircraft.

21. The method of claim 19, wherein the integrating includes tilting the lift fan to an installed lift fan angle relative to the reference.

22. The method of claim 19, which further includes interposing a diffuser duct between the lift fan and the vane assembly.