Hybrid jet/electric VTOL aircraft

• US 8,636,241 B2
• Filed: 04/20/2006
• Issued: 01/28/2014
• Est. Priority Date: 04/20/2005
• Status: Active Grant

• Current Assignee: Sonic Blue Aerospace, Inc.
• Original Assignee: Sonic Blue Aerospace, Inc.
• Inventors: Lugg, Richard H., Youngren, Harold
• Primary Examiner(s): Ellis, Christopher P
• Assistant Examiner(s): Badawi, Medhat
• Application Number:
  US11/912,046
• Publication Number:
  US 20130062455A1
• Time in Patent Office: 2,840 Days
• Field of Search: 244/12.1, 244/12.3, 244/23.R, 244/23.B, 244/55
• US Class Current: 244/12.3
• CPC Class Codes: B64C 29/0025 the propellers being fixed relative to the fuselage
• CPC Class Codes: B64C 39/12 Canard-type aircraft
• CPC Class Codes: B64D 27/24 using steam or spring force jet aircraft B64D27/16
• CPC Class Codes: Y02T 50/40 Weight reduction
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A fixed-wing VTOL aircraft features an array of electric lift fans distributed over the surface of the aircraft. A generator is (selectively) coupled to the gas turbine engine of the aircraft. During VTOL operation of the aircraft, the engine drives the generator to generate electricity to power the lifting fans. Power to the lifting fans is reduced as the aircraft gains forward speed and is increasingly supported by the wings.

Claims

1. A fixed-wing VTOL or STOVL aircraft, comprising:

an airframe comprising a fuselage and forward-swept wings, wherein each of the forward-swept wings includes a root portion;

a thrust-producing gas turbine engine;

an electrical generator that is driven by said gas turbine engine to generate electricity;

a plurality of electric lift-producing fans distributed across said airframe, wherein at least a portion of the electric lift-producing fans are located in the root portion of the forward-swept wings; and

an electrical system configured and arranged to provide electricity generated by said electrical generator to said electric fans to power said electric fans.

2. The aircraft of claim 1, wherein said fans, in total, are able to support at least 25% of the weight of said aircraft.

3. The aircraft of claim 2, wherein said fans, in total, are able to support at least 50% of the weight of said aircraft.

4. The aircraft of claim 3, wherein said fans, in total, are able to support at least 90% of the weight of said aircraft.

5. The aircraft of claim 4, wherein said fans, in total, are able to support the entire weight of said aircraft.

6. The aircraft of claim 1, further comprising a thrust-vectoring nozzle which is able to redirect thrust produced by said engine between a primarily aft-oriented direction and a primarily downward-oriented direction.

7. The aircraft of claim 1, wherein said electrical generator is selectively drivable by said gas turbine engine.

8. The aircraft of claim 7, further comprising an electric clutch by means of which said electrical generator is coupled to and decoupled from said gas turbine engine.

9. The aircraft of claim 1, wherein the root portions of the forward-swept wings are strakes forming part of the fuselage.

10. The aircraft of claim 1, further comprising canards.

11. The aircraft of claim 10, wherein at least some of said fans are located in said canards.

12. A method of operating an aircraft, the aircraft having forward-swept wings, a thrust-producing gas turbine engine, an electrical generator driven by the engine, and a plurality of electrically driven lifting fans, said method comprising:

lifting the aircraft off of a surface using the lifting fans to lift at least some of the weight of the aircraft, wherein the lifting fans are powered by electricity generated by the generator and at least a portion of the lifting fans are located in root portions of forward-swept wings of the aircraft;

decreasing the amount of lift generated by the lifting fans, whereby the lifting fans support a decreased amount of the weight of the aircraft;

increasing thrust produced by the engine and directing at least a component of the thrust in a rearward direction so as to move the aircraft in a forward direction, whereby the forward-swept wings support an increased amount of the weight of the aircraft; and

repeating steps b) and c).

13. The method of claim 12, wherein steps b) and c) are repeated until none of the weight of the aircraft is supported by the lifting fans and all of the weight of the aircraft is supported by the forward-swept wings and any other lift-generating surfaces on the aircraft.

14. The method of claim 12, wherein the lifting fans initially support all of the weight of the aircraft.

15. The method of claim 12, wherein the lifting fans initially support less than all of the weight of the aircraft, said method further comprising initially directing at least a component of the thrust in a downward direction such that the downward-directed component of thrust supports a portion of the weight of the aircraft.

16. The method of claim 15, further comprising redirecting the thrust toward a rearward-acting direction as steps b) and c) are repeated.

17. The method of claim 12, wherein the aircraft initially lifts off of the surface vertically.

18. The method of claim 12, wherein the aircraft initially moves forward over the surface to generate wing-based lift before lifting off of the surface.

19. A method of operating a fixed forward-swept-wing aircraft, the aircraft having a thrust-producing gas turbine engine, an electrical generator, and a plurality of electrically driven lifting fans, at least a portion of which are located in root portions of forward-swept wings of the aircraft, said method comprising:

driving the generator with the gas turbine engine to generate electricity;

driving the lifting fans with the electricity generated by the generator;

hovering the aircraft supported at least in part on lift created by the lifting fans and providing any remaining required lift support by the forward-swept wings.

20. The method of claim 19, wherein the entire weight of the aircraft is supported by the lifting fans during said hovering.

21. The method of claim 19, wherein less than the entire weight of the aircraft is supported by the lifting fans during said hovering, said method further comprising directing thrust produced by the gas turbine engine downward to help support the weight of the aircraft.

22. A method of improving the lifting power loading efficiency of a fixed forward-swept-wing, gas turbine engine-powered VTOL or STOVL aircraft, comprising distributing the lifting power produced by the gas turbine engine to a series of electric lifting fans distributed over the body of the aircraft by converting mechanical power produced by the gas turbine engines to electrical power and using the electrical power to drive the series of electric lifting fans, wherein at least a portion of the series of electric lifting fans is located in root portions of forward-swept wings of the aircraft.