Stall recovery chine spoiler system

Patent metadata

Field	Value
Publication number	US-10858089-B2
Application number	US-201715483304-A
Country	US
Kind code	B2
Filing date	Apr 10, 2017
Priority date	Apr 10, 2017
Publication date	Dec 8, 2020
Grant date	Dec 8, 2020

Abstract

A chine spoiler system enhances aircraft wing stall recovery characteristics while optimizing a maximum lift coefficient (CLMAX) of an aft-swept wing on an aircraft having an engine nacelle mounted below the wing. The system includes a chine located on a surface of the nacelle; the chine is configured to generate a vortex at high angles of attack. The vortex passes over an upper surface of the wing, favorably influencing inboard wing aerodynamics to delay airflow separation from the wing, in advance of a stall. The vortex increases CLMAX, but also creates a nose-up pitching moment on an aft-swept wing, which degrades stall recovery. A chine spoiler system module is configured to render the chine ineffective at predetermined wing flap configurations and angles of attack (typically post CLMAX) to balance the objectives of achieving high pre-stall CLMAX, while providing a nose-down pitching moment increment for improved stall recovery.

First claim

What is claimed is:

1. A system for managing airflow over an aircraft wing including an engine nacelle suspended below the aircraft wing, the system comprising:
a chine mounted to an inboard surface of the engine nacelle, the chine configured to generate a vortex that passes over an inboard upper surface of the aircraft wing;
a chine spoiler system configured to selectively disable the chine, and
a chine spoiler control module operably coupled to the chine spoiler system and programmed to:
send a non-transitory signal to the chine spoiler system to disable the chine when a determined angle of attack of the aircraft wing is above a maximum lift angle of attack of the aircraft wing corresponding to a maximum coefficient of lift of the aircraft wing; and
send a non-transitory signal to the chine spoiler system to optimize post-stall pitch characteristics for improved stall recovery.

2. The system of claim 1 , wherein the chine spoiler control module is programmed to send the non-transitory signal to the chine spoiler system to disable the chine immediately when the determined angle of attack is above the maximum lift angle of attack.

3. The system of claim 1 , wherein the chine spoiler control module is programmed to send the non-transitory signal to the chine spoiler system to disable the chine immediately upon a wing stall event.

4. The system of claim 1 , wherein the aircraft wing is an aft-swept wing.

5. A system for managing airflow over an aircraft wing including an engine nacelle suspended below the aircraft wing, the system comprising:
a fixed chine mounted to an inboard surface of the engine nacelle, the fixed chine configured to generate a vortex that passes over an inboard upper surface of the aircraft wing to influence inboard wing aerodynamics in a manner to increase maximum coefficient of lift of the aircraft wing;
a chine spoiler system comprising a retractable chine spoiler device; and
a chine spoiler control module operably coupled to the chine spoiler system and programmed to send a non-transitory signal to the chine spoiler system to deploy the retractable chine spoiler device during an aerodynamic stall recovery of the aircraft wing.

6. The system of claim 5 , wherein the retractable chine spoiler device comprises a chine spoiler door.

7. The system of claim 6 , wherein the chine spoiler door is mounted on the engine nacelle proximal to the fixed chine to selectively influence airflow over the fixed chine.

8. The system of claim 7 , wherein the chine spoiler control module is further programmed to send a non-transitory signal to the chine spoiler system to extend the chine spoiler door immediately following a stall.

9. An aircraft having an aft-swept wing including an engine nacelle suspended below the aft-swept wing, the aircraft comprising:
a chine spoiler system for managing airflow over the aircraft wing, the chine spoiler system including a chine positioned on an inboard surface of the engine nacelle; and
a chine spoiler control module operably coupled to the chine spoiler system, the chine spoiler control module programmed to:
send a non-transitory signal to the chine spoiler system to disable the chine when a determined angle of attack of the aft-swept wing is above a maximum lift angle of attack of the aft-swept wing corresponding to a maximum coefficient of lift of the aft-swept wing; and
send a non-transitory signal to the chine spoiler system to optimize post-stall pitch characteristics for improved stall recovery.

10. The aircraft of claim 9 , wherein the chine spoiler control module is programmed to send the non-transitory signal to the chine spoiler system to disable the chine immediately when the determined angle of attack is above the maximum lift angle of attack.

11. The aircraft of claim 10 , wherein the chine spoiler control module is programmed to send the non-transitory signal to the chine spoiler system to disable the chine immediately upon a wing stall event.

12. An aircraft having an aft-swept wing including an engine nacelle suspended below the aft-swept wing, the aircraft comprising:
a chine spoiler system for managing airflow over the aircraft wing, the chine spoiler system including:
a fixed chine positioned on an inboard surface of the engine nacelle; and
a retractable chine spoiler door positioned on the engine nacelle, wherein the retractable chine spoiler door is configured to enable or disable the fixed chine; and

a chine spoiler control module operably coupled to the chine spoiler system and programmed to send non-transitory signals to the chine spoiler system to selectively enable and disable the fixed chine as a function of angle of attack of the aft-swept wing, and to disable the fixed chine immediately following a stall of the aft-swept wing.

13. The aircraft of claim 12 , wherein the engine nacelle has a recess, and wherein the retractable chine spoiler door fits within the recess when the fixed chine is enabled.

14. The aircraft of claim 13 , wherein the retractable chine spoiler door has a deployed position for disabling the fixed chine; and wherein the retractable chine spoiler door extends out of the recess when in the deployed position.

15. The aircraft of claim 12 , wherein the retractable chine spoiler door is mounted on the engine nacelle proximal to the fixed chine to selectively influence airflow over the fixed chine when the retractable chine spoiler door is in a deployed position.

16. A method of making a system for an aircraft to enable and disable a chine to selectively control aerodynamic airflow over an upper surface of an aft-swept aircraft wing having an engine nacelle suspended below the aft-swept aircraft wing; the method comprising steps of:
providing a chine on an inboard surface of an aircraft engine nacelle;
providing a chine spoiler system configured to enable and disable the chine;
installing a chine spoiler control module in the aircraft and operatively coupled to the chine spoiler system, the chine spoiler control module receiving signal inputs of aircraft wing flap configuration and angle of attack and being programmed to send a non-transitory signal to the chine spoiler system to disable the chine upon a wing stall event.

17. The method of claim 16 , in which the chine spoiler control module is further programmed to:
send a non-transitory signal to the chine spoiler system to maintain the chine in a normally disabled position at low angles of attack, including cruise phases of flight; and
send non-transitory signals to the chine spoiler system to enable and disable the chine as a function of angle of attack.

18. The method of claim 16 , further comprising configuring the chine to be retractable on the inboard surface of the engine nacelle;
wherein the chine spoiler control module is programmed to send a non-transitory signal to the chine spoiler system to disable the chine by retracting the chine.

19. The method of claim 16 , further comprising the step of fixing the chine to the engine nacelle, affixing a deployable chine spoiler door on the engine nacelle, and positioning the deployable chine spoiler door proximally with respect to the chine to influence airflow over the chine.

20. The method of claim 19 , in which the chine spoiler control module is programmed to send a non-transitory signal to the chine spoiler system to disable the chine by deploying the deployable chine spoiler door.

Assignees

• Boeing Co

Inventors

• Bays-Muchmore C Byram

Classifications

• B64C5/12

  for retraction against or within fuselage or nacelle · CPC title

• Y02T50/10

  Drag reduction · CPC title

• B64C23/06 Primary

  by generating vortices · CPC title

• B64C3/10

  Shape of wings · CPC title

• B64D29/02

  associated with wings · CPC title