ONE PIECE INLET LIP SKIN DESIGN

• US 20150260104A1
• Filed: 03/15/2014
• Published: 09/17/2015
• Est. Priority Date: 03/15/2014
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Wilson, Ronnie, Stemple, Alan D.
• Granted Patent: US 9,664,113 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B64D 29/06 Attaching of nacelles, fairings or cowlings
• CPC Class Codes: B64D 33/02 of combustion air intakes air intakes for gas-turbine plants or jet-propulsion plants per se F02C7/04; air intakes for combustion engines in general F02M35/00
• CPC Class Codes: F02C 7/04 Air intakes for gas-turbine plants or jet-propulsion plants
• CPC Class Codes: F02C 7/20 Mounting or supporting of plant; Accommodating heat expansion or creep
• CPC Class Codes: Y10T 29/49229 Prime mover or fluid pump making

Abstract

An aircraft engine inlet incorporates a lip skin having a skin web with a plurality of stiffeners integrally extending from the skin web. An aft edge land integrally extends from the skin web at an outer rim and an inner edge land integrally extends from the skin web at an inner rim. A central land integrally extends from the skin web with the plurality of stiffeners extending between said aft edge land and the central land.

Claims

1. An aircraft engine inlet comprising:

a lip skin having

a skin web;

a plurality of stiffeners integrally extending from the skin web;

an aft edge land integrally extending from the skin web at an outer rim;

an inner edge land integrally extending from the skin web at an inner rim; and

,

a central land integrally extending from the skin web, said plurality of stiffeners extending between said aft edge land and said central land.

2. The aircraft engine inlet as defined in claim 1 wherein the plurality of stiffeners comprises two stiffeners and the stiffeners extend substantially fore and aft on the skin web.

3. The aircraft engine inlet as defined in claim 1 wherein the stiffeners are asymmetrically located about an inlet axis.

4. The aircraft engine inlet as defined in claim 3 wherein the stiffeners are located at an offset angle of about 11 degrees.

5. The aircraft engine inlet as defined in claim 4 where in the stiffeners are separated by a clocking angle of about 25 degrees.

6. The aircraft engine inlet as defined in claim 1 further comprising:

a forward bulkhead engaged between the central land and the inner edge land.

7. The aircraft engine inlet as defined in claim 6 further comprising an inner barrel, said inner barrel abutting the inner rim and said forward bulkhead having an inner flange spanning and connecting the inner edge land and a mating surface on the inner barrel.

8. The aircraft engine inlet as defined in claim 7 further comprising an outer barrel abutting the outer rim and a first stringer engaging the aft edge land and outer barrel.

9. The aircraft engine inlet as defined in claim 8 further comprising an aft bulkhead inter connected to a second stringer and an aft edge of the outer barrel,

10. The aircraft engine inlet as defined in claim 9 further comprising a bracket attaching the inner barrel to internal nacelle structure and an inner attach angle engaging the aft bulkhead and the bracket.

11. A method for fabricating an engine inlet comprising:

forming a lip skin by spin forming with a thickness at least as thick as a thickest land or stiffener;

determining a pattern of lands and stiffeners to meet structural requirements for aerodynamic, sonic and step loads;

forming a plurality of lands and stiffeners integrally in the lip skin pursuant to the determined pattern.

12. The method as defined in claim 11 wherein the step of forming comprises machining the plurality of lands and stiffeners integrally in the lip skin.

13. The method as defined in claim 11 wherein the step of forming comprises chemical milling the plurality of lands and stiffeners integrally in the lip skin.

14. The method as defined in claim 12 wherein the plurality of lands and stiffeners are machined to a common thickness.

15. The method as defined in claim 12 wherein the plurality of lands and stiffeners are machined to differing thicknesses.

16. The method as defined in claim 11 further comprising:

attaching a forward bulkhead to a central land; and

abutting the lip skin at an outer rim to an outer barrel and an inner rim at an inner barrel.

17. The method as defined in claim 16 further comprising engaging a first stringer to an aft edge land on the lip skin and the outer barrel.

18. The method as defined in claim 17 further comprising engaging an outer periphery of the forward bulkhead to an inner edge land and a mating surface on the inner barrel.

19. The method as defined in claim 18 further comprising attaching an aft bulkhead to the outer barrel using a second stringer and to an L bracket on the inner barrel using an inner attach angle.

20. The method as defined in claim 19 further comprising attaching the L bracket to internal nacelle structure and the second stringer to an external skin of the nacelle.