System and method for utilizing stored electrical energy for VTOL aircraft thrust enhancement and attitude control

• US 20070057113A1
• Filed: 12/22/2005
• Published: 03/15/2007
• Est. Priority Date: 12/22/2004
• Status: Active Grant

• Current Assignee: Aurora Flight Sciences Corporation (The Boeing Co.)
• Original Assignee: Fourth Third LLC
• Inventors: Parks, Robert
• Granted Patent: US 7,857,254 B2
• Time in Patent Office: Days
• US Class Current: 244/12.500
• CPC Class Codes: B64C 15/00 Attitude, flight direction, or altitude control by jet reaction
• CPC Class Codes: B64C 29/0025 the propellers being fixed relative to the fuselage
• CPC Class Codes: B64C 29/0033 the propellers being tiltable relative to the fuselage
• CPC Class Codes: B64C 29/0041 the lift during taking-off being created by jet motors
• CPC Class Codes: B64C 29/0083 the lift during taking-off being created by several motors of different type

Abstract

A system and method are provided for ashort take-off and landing/vertical take-off and landing aircraft that stores required take-off power in the form of primarily an electric fan engine, and secondarily in the form of an internal combustion engine, wherein the combined power of the electric fan and internal combustion engines can cause the STOL/VTOL A/C to take-off in substantially less amount of time and space than other STOL/VTOL A/C, and further wherein the transition from vertical to horizontal thrust is carefully executed to rapidly rise from the take-off position to a forward flight position, thereby minimizing the necessity for a larger electric fan engine.

Claims

1. A vertical take-off and landing (VTOL) aircraft, comprising:

a primary engine configured to produce thrust for forward flight and thrust for hovering;

a plurality of electrically-driven fans arranged about a periphery of a fuselage and wings of the VTOL aircraft,

wherein airflow provided by each of the electrically-driven fans is oriented substantially perpendicular to the fuselage of the VTOL aircraft for producing thrust for hovering;

a thrust control circuit in communication with each of the plurality of electrically-driven fans,

wherein the thrust control circuit is configured to independently control the thrust for hovering provided by each of the plurality of electrically-driven fans to alter a total thrust for hovering provided by the plurality of electrically-driven fans and to alter pitch and roll moments of the VTOL aircraft while hovering;

a plurality of vanes located in a fan exhaust of each of the plurality of electrically-driven fans; and

an attitude control circuit in communication with each of the plurality of vanes and the thrust control circuit,

wherein the attitude control circuit is configured to independently control deflection of each of the plurality of vanes for re-directing the thrust for hovering provided by each of the plurality of electrically-driven fans to control a yaw moment of the VTOL aircraft while hovering.

2. The VTOL aircraft of claim 1, wherein the primary engine is configured to be tilted to a position substantially perpendicular to the fuselage of the VTOL aircraft to produce thrust for hovering.

3. The VTOL aircraft of claim 1, wherein a nozzle of the primary engine is configured to be re-directed to produce thrust for hovering.

4. The VTOL aircraft of claim 1, wherein the primary engine comprises a fuel-powered engine.

5. The VTOL aircraft of claim 4, wherein the fuel-powered engine comprises a turbo jet engine.

6. The VTOL aircraft of claim 4, wherein the fuel-powered engine comprises a turbo fan engine.

7. The VTOL aircraft of claim 1, wherein the plurality of electrically-driven fans comprises three electrically-driven fans.

8. The VTOL aircraft of claim 7, wherein the three electrically-driven fans are located at substantially equally-spaced angles about a center of the VTOL aircraft.

9. The VTOL aircraft of claim 1, wherein each of the plurality of electrically-driven fans comprises an airflow area that is greater than the primary engine.

10. The VTOL aircraft of claim 1, wherein the plurality of electrically-driven fans are oriented such that the airflow provided by the plurality of electrically-driven fans prevents re-ingestion of exhaust from the primary engine into an air inlet of the primary engine.

11. The VTOL aircraft of claim 1, wherein the plurality of electrically-driven fans are oriented such that the airflow provided by the plurality of electrically-driven fans prevents high-speed exhaust from the primary engine from creating a low pressure region under the VTOL aircraft while the VTOL aircraft is grounded.

12. The VTOL aircraft of claim 1, wherein the thrust control circuit controls the thrust for hovering provided by each of the plurality of electrically-driven fans by varying a RPM of a respective electrically-driven fan.

13. The VTOL aircraft of claim 1, wherein the thrust control circuit controls the thrust for hovering provided by each of the plurality of electrically-driven fans by varying a fan rotor pitch of a respective electrically-driven fan.

14. The VTOL aircraft of claim 1, wherein the thrust control circuit controls the thrust for hovering provided by each of the plurality of electrically-driven fans by deflecting drag-producing flaps located in the fan exhaust of a respective electrically-driven fan.

15. The VTOL aircraft of claim 1, wherein the plurality of vanes are oriented with pivot axes substantially radial to a center of mass of the VTOL aircraft.

16. The VTOL aircraft of claim 1, wherein the plurality of vanes are oriented with pivot axes substantially parallel to the fuselage of the VTOL aircraft.

17. The VTOL aircraft of claim 1, wherein electricity for powering each of the plurality of electrically-driven fans is provided by an electrical generator powered by the primary engine.

18. The VTOL aircraft of claim 1, wherein electricity for powering each of the plurality of electrically-driven fans is provided by an electricity storage unit associated with the plurality of electrically-driven fans.

19. The VTOL aircraft of claim 18, wherein the electricity storage unit comprises batteries.

20. A method of controlling thrust and attitude of a vertical take-off and landing (VTOL) aircraft, comprising the steps of:

a.) producing thrust for forward flight and thrust for hovering using a primary engine;

b.) producing thrust for hovering using a plurality of electrically-driven fans arranged about a periphery of a fuselage and wings of the VTOL aircraft,

wherein airflow provided by each of the electrically-driven fans is oriented substantially perpendicular to the fuselage of the VTOL aircraft for producing thrust for hovering;

c.) independently controlling the thrust for hovering provided by each of the plurality of electrically-driven fans to alter a total thrust for hovering provided by the plurality of electrically-driven fans and to alter pitch and roll moments of the VTOL aircraft while hovering; and

d.) independently controlling deflection of each of a plurality of vanes, located in a fan exhaust of each of the plurality of electrically-driven fans, for re-directing the thrust for hovering provided by each of the plurality of electrically-driven fans to control a yaw moment of the VTOL aircraft while hovering.

21. The method of claim 20, comprising the step of:

e.) tilting the primary engine to a position substantially perpendicular to the fuselage of the VTOL aircraft to produce thrust for hovering.

22. The method of claim 20, comprising the step of:

f.) re-directing a nozzle of the primary engine to produce thrust for hovering.

23. The method of claim 20, wherein the primary engine comprises a fuel-powered engine.

24. The method of claim 20, wherein the plurality of electrically-driven fans comprises three electrically-driven fans.

25. The method of claim 24, wherein the three electrically-driven fans are located at substantially equally-spaced angles about a center of the VTOL aircraft.

26. The method of claim 20, wherein each of the plurality of electrically-driven fans comprises an airflow area that is greater than the primary engine.

27. The method of claim 20, wherein the plurality of electrically-driven fans are oriented such that the airflow provided by the plurality of electrically-driven fans prevents re-ingestion of exhaust from the primary engine into an air inlet of the primary engine.

28. The method of claim 20, wherein the plurality of electrically-driven fans are oriented such that the airflow provided by the plurality of electrically-driven fans prevents high-speed exhaust from the primary engine from creating a low pressure region under the VTOL aircraft while the VTOL aircraft is grounded.

29. The method of claim 20, wherein step (c) comprises the step of:

e.) varying a RPM of a respective electrically-driven fan to control the thrust for hovering provided by each of the plurality of electrically-driven fans.

30. The method of claim 20, wherein step (c) comprises the step of:

e.) varying a fan rotor pitch of a respective electrically-driven fan to control the thrust for hovering provided by each of the plurality of electrically-driven fans.

31. The method of claim 20, wherein step (c) comprises the step of:

e.) deflecting drag-producing flaps located in the fan exhaust of a respective electrically-driven fan to control the thrust for hovering provided by each of the plurality of electrically-driven fans.

32. The method of claim 20, wherein the plurality of vanes are oriented with pivot axes substantially radial to a center of mass of the VTOL aircraft.

33. The method of claim 20, wherein the plurality of vanes are oriented with pivot axes substantially parallel to the fuselage of the VTOL aircraft.

34. The method of claim 20, comprising the step of:

g.) powering each of the plurality of electrically-driven fans by an electrical generator powered by the primary engine.

35. The method of claim 20, comprising the step of:

h.) powering each of the plurality of electrically-driven fans by an electricity storage unit associated with the plurality of electrically-driven fans.

36. The method of claim 35, wherein the electricity storage unit comprises batteries.

37. The method of claim 35, wherein electricity storage units are separately mounted within a vicinity of each of the plurality of electrically-driven fans and in thermal contact with a duct of a respective electrically-driven fan, and

wherein the method comprises the step of:

f.) cooling the electricity storage units using airflow from operation of the respective electrically-driven fans.

38. The method of claim 35, comprising the step of:

f.) re-charging the electricity storage units using an electrical generator powered by the primary engine.

39. The method of claim 35, comprising the step of:

f.) re-charging the electricity storage units by an external electrical energy source while the VTOL aircraft is grounded.

40. The method of claim 20, comprising the step of:

e.) covering each of the electrically-driven fans with movable doors during forward flight.

41. The method of claim 20, comprising the step of:

e.) independently controlling deflection of each of the plurality of vanes to produce side forces in a direction for altering a position of the VTOL aircraft while hovering.