Aircraft with dual flight regimes

• US 20110031355A1
• Filed: 05/29/2010
• Published: 02/10/2011
• Est. Priority Date: 06/04/2009
• Status: Active Grant

• Current Assignee: Alvarez Calderon F., Alberto
• Original Assignee: Alvarez Calderon F., Alberto
• Inventors: Alvarez Calderon F., Alberto
• Granted Patent: US 8,690,096 B2
• Time in Patent Office: Days
• US Class Current: 244/7.R
• 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 3/10 Shape of wings
• CPC Class Codes: B64C 39/08 having multiple wings
• CPC Class Codes: Y02T 50/10 Drag reduction

Abstract

The aircraft is capable of two distinct fuel-efficient flight regimes: one is a vertical flight regime supported by two large two-bladed rotors with low disc loading located on right and left longitudinal booms. The booms extend between outboard regions of a front wing and inboard regions of a rear wing that has a larger span an area. The other flight regime is high speed up to high subsonic Mach number with the aircraft supported by wing lift with high wing loading, and with the rotors stopped and faired with minimal local drag contiguous to the booms. The longitudinal location of the aircrafts center of gravity, aerodynamic center and the center of the rotors are in close proximity. The front wing is preferably swept back, and the rear wing is preferably of W planform.

Claims

1. An aircraft having a front wing and a rear wing, two longitudinal streamlined bodies attached to lateral portions of said wings, with each of said longitudinal bodies supporting a rotor (all figures except FIG. 5).

2. Claim 1 in which each of said rotors has two blades, with said blades adapted to be stopped in flight with their long dimension adjacent to said longitudinal bodies in a low drag disposition (all figures except FIG. 5).

3. Claim 1 in which said front wing has backward sweep, and said rear wing has a W shaped planform (FIGS. 1, 4, 6).

4. Claim 1 in which said front wing is swept forward, and said rear wing is swept backwards (FIG. 2).

5. Claim 1 in which said front wing is swept forward, and said rear wing has a W-planform (FIG. 3).

6. Claim 1 further characterizes in having a central fuselage between said lateral bodies (FIG. 1).

7. Claim 1 further characterized in that the longitudinal positions of the center of gravity of said aircraft, of the aerodynamic center of said aircraft, and the axis of rotation of said rotors are in dose proximity. (FIG. 1).

8. The structure of claim 1 further characterized in that said aircraft is capable of operating in vertical flight regime with said rotors operative, and in a high speed regime in which said rotors are stopped aligned with said bodies. (FIGS. 1, 4, 6).

9. The structure of claim 1 further characterized in having blades of said rotors with fixed pitch and free of articulations. (Part of FIG. 6).

10. The structure of claim 2 further characterized in that said longitudinal bodies have movable surface portions with a first position clear of the path of said rotors when in operation in vertical flight regime, and a second position enclosing said rotors when stopped in a low drag disposition in high speed regime (FIG. 7).

11. The structure of claim 2 further characterized in that each of said rotors has a motor with a shaft driving said rotors, with said rotors adapted to move in a vertical direction between a position for vertical flight regime in which said blades are operative at a vertical distance spaced from said longitudinal bodies, and a position for high speed regime in which said blades are stopped and contiguous to said longitudinal bodies (FIG. 8).

12. The structure of claim 2 further characterized in having a central body portion between said longitudinal bodies extending to the front of said forward wing, with said center body portion having a small two bladed rotor that operates during vertical flight regime with an approximately horizontal rotor plane, said small rotor stopped with said blades aligned and stored within said central body during high speed regime (FIG. 6).

13. Claim 3 further characterized in that the span of said rear wing is larger than the span of said front wing, with a portion of said longitudinal bodies adjacent their forward ends attached to said front wings adjacent the tips of said front wings, and with a rear portion of said longitudinal bodies attached to a portion of said rear wings at a location adjacent the rearmost change of sweep of said rear wing. (FIGS. 1, 3, 4, 6).

14. Claim 5 characterized in that portions of said wings in planform and portions of said central fuselage in planform are contiguous to portions of the tip paths of said rotors, to induce lifting forces on part of said wings and said fuselage when in vertical flight. (FIG. 2).

15. The structure of claim 12 being further characterized in that the horizontal plane of said operational small rotor can be tilted laterally to provide yaw control to said aircraft. (Part of FIG. 6).

16. The structure of claim 2, in which said longitudinal bodies have flap in their lower surfaces to laterally direct portions of the slipstream of said rotors for yaw control of said aircraft. (Part of FIG. 6).

17. The structure of claim 2, that is dependent on claim 1, incorporating the limiting features of claim 6, claim 12, and claim 14, but written without referring to claims 6, 12, and 14. (FIG. 1).

18. Claim 1, in which said aircraft has a vertical fin with a rotor having variable pitch blades and a vertical plane of rotation housed within said fin having approximately vertical side surfaces, with semi-circular doors provided on said side surfaces which enclose said rotor when inoperative during high speed flight regime, and open about an equatorial hinge line by approximately 90 degrees when in slow speed flight regime. (Part of FIG. 6)

19. A rotor having blades free of flapping articulation with blades that have tip portions incorporating metal with very high density, whereby said rotor has a substantially increased gyroscopic stabilizing effect in addition to its aerodynamic lift effects. (Part of FIG. 6).

20. An aircraft having a front wing, a rear wing, a central fuselage, and laterally extending right and left streamlined bodies between said wings with their root portions attached to said fuselage and with the outboard tips of said lateral bodies supporting a rotor. FIG. 5.