FAST HYBRID HELICOPTER WITH LONG RANGE

• US 20090321554A1
• Filed: 05/22/2008
• Published: 12/31/2009
• Est. Priority Date: 05/22/2007
• Status: Active Grant

• Current Assignee: Airbus Helicopters
• Original Assignee: Eurocopter
• Inventors: ROESCH, Philippe
• Granted Patent: US 8,181,901 B2
• Time in Patent Office: Days
• US Class Current: 244/6
• CPC Class Codes: B64C 2027/8281 comprising horizontal tail planes
• CPC Class Codes: B64C 27/26 characterised by provision of fixed wings

Abstract

A hybrid helicopter (1) includes firstly an airframe provided with a fuselage (2) and a lift-producing surface (3), together with stabilizer surfaces (30, 35, 40), and secondly with a drive system constituted by:

• • a mechanical interconnection system (15) between firstly a rotor (10) of radius (R) with collective pitch and cyclic pitch control of the blades (11) of the rotor (10), and secondly at least one propeller (6) with collective pitch control of the blades of the propeller (6); and
  • at least one turbine engine (5) driving the mechanical interconnection system (15). The device is remarkable in that the outlet speeds of rotation of the at least one turbine engine (5), of the at least one propeller (6), of the rotor (10), and of the mechanical interconnection system (15) are mutually proportional, the proportionality ratio being constant.

Claims

1. A hybrid helicopter (1) having a long range and a high forward speed, the helicopter comprising:

an airframe made up of;

a fuselage (2);

a lift-providing surface (3) secured to the fuselage (2); and

stabilizing and maneuvering surfaces, namely for pitch;

a horizontal stabilizer (30) with at least one pitch control surface (35) that is movable relative to the front portion (34); and

for steering;

at least one suitable stabilizer (40); and

an integrated drive system (4) constituted by;

a mechanical interconnection system (15) between firstly a rotor (10) of radius (R) with collective pitch and cyclic pitch control of the blades (11) of said rotor (10), and secondly at least one propeller (6) with collective pitch control of the blades of said propeller (6); and

at least one turbine engine (5) driving the mechanical interconnection system (15);

wherein the outlet speeds of rotation of said at least one turbine engine (5), of said at least one propeller (6), of said rotor (10), and of said mechanical interconnection system (15) are mutually proportional, the proportionality ratio being constant regardless of the flight configuration of the hybrid helicopter (1) under normal operating conditions of the integrated drive system.

2. A hybrid helicopter (1) according to claim 1, wherein the stabilizer (40) comprises at the front a non-moving fin (44) fitted with a movable steering rudder (45) for providing the pilot with yaw control.

3. A hybrid helicopter (1) according to claim 1, wherein said rotor (10) firstly exerts all of the lift needed for takeoff, for landing, for hovering, and for flying vertically, and secondly always provides a fraction of the lift needed for cruising flight, said rotor (10) being always driven in rotation by said at least one turbine engine (5), without participating in traction or in drag, with reduced absorbed power.

4. A hybrid helicopter (1) according to claim 1, wherein said rotor (10) firstly exerts all of the lift needed for takeoff, for landing, for hovering, and for flying vertically, and secondly always provides a fraction of the lift needed for cruising flight, said rotor (10) being always driven in rotation by said at least one turbine engine (5), with reduced contribution to traction but no contribution to drag, and with reduced absorbed power.

5. A hybrid helicopter (1) according to claim 3, wherein the lift developed by the rotor (10) is about 1.05 times the weight of the hybrid helicopter (1) for a flightpath airspeed of zero, and lies in the range 0.6 to 0.9 times the weight of the helicopter at maximum flightpath airspeed.

6. A hybrid helicopter (1) according to claim 1, wherein the maximum flightpath airspeed is about 220 kt for a maximum authorized takeoff weight of the hybrid helicopter (1) of about 8 t.

7. A hybrid helicopter (1) according to claim 1, wherein the span of the wing (3) made up of two half-wings (8) is substantially equal to the radius (R) of the rotor (10).

8. A hybrid helicopter (1) according to claim 1, wherein the wing (3) is in the high position relative to the fuselage (2).

9. A hybrid helicopter (1) according to claim 8, wherein the dihedral angle of the wing (3) is negative.

10. A hybrid helicopter (1) according to claim 1, wherein the wing (3) is in the low position relative to the fuselage (2).

11. A hybrid helicopter (1) according to claim 10, wherein the dihedral angle of the wing (3) is positive.

12. A hybrid helicopter (1) according to claim 1, wherein the wing (3) is in an intermediate position between the high position and the low position.

13. A hybrid helicopter (1) according to claim 7, wherein the aspect ratio (λ

) of the wing (3) is about 5.30.

14. A hybrid helicopter (1) according to claim 1, wherein the diameter (D) of the rotor (10) is about 16 m.

15. A hybrid helicopter (1) according to claim 1, wherein the lift/drag ratio (f) of the rotor (10) is about 12.2 for a flightpath airspeed greater than 150 kt.

16. A hybrid helicopter (1) according to claim 1, wherein the lift/drag ratio (F) of the assembly comprising the wing (3) and the rotor (10) is about 12 for a flightpath airspeed greater than 150 kt.

17. A hybrid helicopter (1) according to claim 1, wherein the diameter of a propeller (6) lies in the range 2.5 m to 4.5 m.

18. A hybrid helicopter (1) according to claim 1, wherein the diameter of a propeller (6) is 2.6 m.

19. A hybrid helicopter (1) according to claim 1, wherein said hybrid helicopter (1) is fitted with two propellers (6), each propeller (6) being situated at an outside end of the wing (3).

20. A hybrid helicopter (1) according to claim 1, wherein the collective pitch and the cyclic pitch of the blades (11) of the rotor (10) are controlled and adapted as a function of flight conditions.

21. A hybrid helicopter (1) according to claim 1, wherein the collective pitch of the propellers (6) is controlled and adapted as a function of flight conditions.

22. A hybrid helicopter (1) according to claim 1, wherein the horizontal stabilizer (30) and the vertical stabilizer (40) together form an upside-down U-shaped unit relative to the fuselage (2).

23. A hybrid helicopter (1) according to claim 1, wherein two turbine engines (5) are disposed on the fuselage (2).

24. A hybrid helicopter (1) according to claim 1, wherein two turbine engines (5) are disposed on the wing (3), the turbine engine (5) being located on either side of said fuselage (2).

25. A hybrid helicopter (1) according to claim 1, wherein the antitorque function is performed by a single propeller (6).

26. A hybrid helicopter (1) according to claim 1, wherein the antitorque function is performed by differential thrust between the two propellers (6), one exerting thrust towards the front and the other exerting thrust towards the rear of the hybrid helicopter (1).