Rotary wing rotorcraft having a plurality of propellers

Patent metadata

Field	Value
Publication number	US-9272789-B2
Application number	US-201414291655-A
Country	US
Kind code	B2
Filing date	May 30, 2014
Priority date	May 30, 2013
Publication date	Mar 1, 2016
Grant date	Mar 1, 2016

Abstract

A hybrid aircraft ( 1 ) having a fuselage ( 2 ) extending longitudinally along an anteroposterior plane of symmetry (PSYM) from the rear ( 4 ) of the aircraft ( 1 ) towards the front ( 3 ) of the aircraft ( 1 ). The aircraft ( 1 ) has a rotary wing ( 6 ) carried by the fuselage ( 2 ) of a lift surface ( 10 ) fastened to the fuselage ( 2 ) and constituted by a first half-wing ( 11 ) and a second half-wing ( 12 ). The aircraft ( 1 ) has a first propulsion unit ( 30 ) carried by the first half-wing ( 11 ) and a second propulsion unit ( 40 ) carried by the second half-wing ( 12 ). Each propulsion unit ( 30, 40 ) includes at least one tractor propeller ( 31, 32, 41, 42 ), and at least one propulsion unit has two propellers ( 31 - 32, 41 - 42 ) on the same axis, each of said propellers rotating about an axis of rotation (AX) that is offset transversely from said anteroposterior plane of symmetry (PSYM).

First claim

What is claimed is:

1. A hybrid aircraft having a fuselage extending longitudinally along an anteroposterior plane of symmetry (PSYM) from the rear of the aircraft towards the front of the aircraft, the aircraft having a rotary wing carried by the fuselage, the aircraft being provided with a lift surface fastened to the fuselage and constituted by a first half-wing and a second half-wing situated on either side of the fuselage, the aircraft having a first propulsion unit carried by the first half-wing and a second propulsion unit carried by the second half-wing, wherein each respective propulsion unit is disposed about a respective axis of rotation (AX) that is offset transversely from the anteroposterior plane of symmetry (PSYM), the first propulsion unit including both a first propeller and a second propeller on a first one of the respective axes, the first propeller and the second propeller being arranged back to back and suitable in a normal thrust mode of operation respectively for generating thrust towards the front of the aircraft and thrust directed towards the rear of the aircraft, this first propulsion unit always presenting one propeller that generates no thrust during hovering flight.

2. The aircraft according to claim 1 , wherein the first propeller and the second propeller are arranged to be contrarotating.

3. The aircraft according to claim 1 , wherein the first propeller and the second propeller are arranged to rotate in the same direction.

4. The aircraft according to claim 1 , wherein the first propeller and the second propeller are situated on the same side of the first half-wing.

5. The aircraft according to claim 1 , wherein the first propeller and the second propeller are situated on opposite sides of the same half-wing.

6. The aircraft according to claim 1 , wherein the first propeller of the first propulsion unit generates no thrust during hovering flight, and the second propeller of the first propulsion unit generates no thrust during forward flight.

7. The aircraft according to claim 1 , wherein the second propulsion unit includes both a third propeller and a fourth propeller on a second one of the respective axes, each generating thrust directed towards the front of the aircraft in a normal thrust mode of operation.

8. The aircraft according to claim 1 , wherein the second propulsion unit includes a single propeller that generates thrust directed towards the front of the aircraft in a normal thrust mode of operation.

9. The aircraft according to claim 1 , wherein the rotary wing has a lift rotor that rotates in the clockwise direction when seen from above, and the first propulsion unit is situated on the right of the fuselage when seen from above, the second propulsion unit being situated on the left of the fuselage when seen from above.

10. The aircraft according to claim 1 , wherein the rotary wing has a lift rotor rotating counterclockwise as seen from above, and the first propulsion unit is situated on the left of the fuselage as seen from above, the second propulsion unit being situated on the right of the fuselage as seen from above.

11. A method of optimizing the ground clearance (GS 2 ) of a hybrid aircraft provided with a fuselage extending longitudinally along an anteroposterior plane of symmetry (PSYM) from the rear of the aircraft towards the front of the aircraft, the aircraft having a rotary wing carried by the fuselage, the aircraft being provided with a lift surface fastened to the fuselage and constituted by a first half-wing and a second half-wing situated on either side of the fuselage, the aircraft having a first propulsion unit carried by the first half-wing and a second propulsion unit carried by the second half-wing, the method being characterized by the following steps:
fitting the second propulsion unit with at least one propeller; and
fitting the first propulsion unit with a first propeller and a second propeller that are on the same axis in order to minimize the diameter of the propellers, the first propeller and the second propeller mounted back to back, which propellers are suitable for generating respectively thrust directed towards the front of the aircraft and thrust that is directed towards the rear of the aircraft in a normal thrust mode of operation, this first propulsion unit always presenting one propeller that generates no thrust during hovering flight.

12. The method according to claim 11 , further comprising the following steps:
during hovering flight, setting the first propeller of the first propulsion unit so that the first propeller generates no thrust; and
during forward flight, setting the second propeller of the first propulsion unit so that the second propeller generates no thrust, or else causing the second propeller of the first propulsion unit to operate in a reverse thrust mode of operation.

13. A hybrid aircraft having:
a fuselage extending longitudinally along an anteroposterior plane of symmetry (PSYM) from the rear of the aircraft towards the front of the aircraft;
a rotary wing carried by the fuselage;
a lift surface fastened to the fuselage and constituted by a first half-wing and a second half-wing situated on either side of the fuselage; and
a first propulsion unit carried by the first half-wing and a second propulsion unit carried by the second half-wing, wherein each respective propulsion unit is disposed about a respective axis of rotation (AX) that is offset transversely from the anteroposterior plane of symmetry (PSYM), the first propulsion unit including both a first propeller and a second propeller on a first one of the respective axes arranged back to back and suitable in a normal thrust mode of operation respectively for generating thrust towards the front of the aircraft and thrust directed towards the rear of the aircraft, this first propulsion unit always presenting one propeller that generates no thrust during hovering flight, wherein the first propeller of the first propulsion unit generates no thrust during hovering flight, and the second propeller of the first propulsion unit operates in the reverse thrust mode of operation in forward flight.

14. The aircraft of claim 13 , wherein the first propeller and the second propeller are arranged to be contrarotating.

15. The aircraft of claim 13 , wherein the first propeller and the second propeller are arranged to rotate in the same direction.

16. The aircraft of claim 13 , wherein the second propulsion unit includes both a third propeller and a fourth propeller on a second one of the respective axes, each generating thrust directed towards the front of the aircraft in a normal thrust mode of operation.

17. The aircraft of claim 13 , wherein the second propulsion unit includes a third propeller that generates thrust directed towards the front of the aircraft in a normal thrust mode of operation.

18. The aircraft of claim 13 , wherein the first propeller and the second propeller are situated on opposite sides of the same half-wing.

19. The aircraft of claim 1 , wherein the first propeller and second propeller are each respectively driven by at least one associated engine.

20. The method of claim 11 , wherein the first propeller and second propeller are each respectively driven by at least one associated engine.

Assignees

• Airbus Helicopters

Inventors

• Prud Homme-Lacroix Pierre

Classifications

• B64D27/02

  Aircraft characterised by the type or position of power plants · CPC title

• B64C27/22 Primary

  Compound rotorcraft, i.e. aircraft using in flight the features of both aeroplane and rotorcraft · CPC title

• B64C27/26

  characterised by provision of fixed wings · CPC title

• B64C27/82

  characterised by the provision of an auxiliary rotor or fluid-jet device for counter-balancing lifting rotor torque or changing direction of rotorcraft · CPC title

• B64D27/22

  using atomic energy · CPC title