The present disclosure relates generally to the field of engine mounts for aircraft and, more specifically, to engine mounts constructed from multiple sections to facilitate attachment of the engine to a wing of an aircraft.
Certain aircraft include wings with structural members that support an engine. The structural member is designed to support and securely connect the engine to the aircraft. Because of the position of the structural member relative to the engine, the structural member affects the air flow and thus the operation of the engine. The aerodynamics of the structural member has greater effect in aircraft with particular engines, such as those that include exposed blades. One type is an unducted turbofan engine that includes exposed fan blades in combination with a gas turbine engine. The fan aerodynamics become highly sensitive to the shape and size of the structural member.
The design aspects of the structural member are generally something of a compromise between the aerodynamic and structural requirements. The aerodynamic needs prefer that the structural member be small and unobtrusive to reduce aerodynamic drag. The structural needs require that the structural member have adequate size and dimensions to support the engine.
Thus, there is a need for a structural member that effectively mounts an engine to an aircraft and also includes an effective aerodynamic design.
One aspect is directed to a fitting to mount an engine to a wing of an aircraft. The fitting comprises a body with a first end and a second end. A first pocket is positioned at the first end with the first pocket sized to receive the forward engine mount fitting. A second pocket is positioned at the second end with the second pocket sized to receive a strut box of the wing of the aircraft. The body comprises a first section and a second section that are connected together.
In another aspect, the first section and the second section abut together at a joint that extends along a length of the body.
In another aspect, the body comprises a tapered shape that increases from the first end to the second end.
In another aspect, the taper is consistent along the length from the first end to the second end.
In another aspect, the first section is a mirror image of the second section.
In another aspect, the first end is open to receive the forward engine mount fitting and the second end is open to receive the strut box.
In another aspect, flanges extend along a first side of the body and an opposing second side of the body with the flanges comprising a central flange section and laterally-extending stiffeners that are spaced apart along a length of a central flange section.
In another aspect, a first portion of the flanges are mounted to the first section and a second portion of the flanges are mounted to the second section.
In another aspect, a receptacle is positioned along one side of the body with the receptacle comprising opposing lateral walls that extend outward from the side of the body and one or more ribs that extend between the lateral walls.
In another aspect, ribs extend outward from inner sides of the first section and the second section with the ribs abutting together when the first section and the second section are connected together.
In another aspect, the body comprises two or more flat sides.
One aspect is directed to a fitting to mount an engine to a wing of an aircraft. The fitting comprises a first section and a second section each comprising: a lateral side; a top side; a bottom side; and an inner side. The first section and the second section are configured to connect together along the inner sides to form a body with the body comprising: a first side formed by the lateral side of the first section; a second side formed by the lateral side of the second section; a third side formed by the top sides of the first section and the second section; and a fourth side formed by the bottom sides of the first section and the second section.
In another aspect, an interior space is positioned within the body with the interior space comprising a first pocket positioned at a first end of the body to receive a forward engine mount fitting and a second pocket positioned at a second end of the body to receive the strut box of the wing.
In another aspect, the first pocket and the second pocket are each surrounded by the first section and the second section.
In another aspect, the first section is a mirror image of the second section.
In another aspect, ribs extend outward from inner faces of the lateral sides of the first section and the second section with the ribs having exposed ends that abut together when the first section and the second section are connected together.
In another aspect, the lateral sides are flat to connect with brackets of an aft engine mount fittings.
In another aspect, flanges extend outward from the body and comprising a flange section and lateral stiffeners with the flanges configured to form a structural interface that takes both shear and tension.
In another aspect, fasteners that extend through and connect the first section to the second section.
In another aspect, the first section and the second section abut together with at a joint that extends longitudinally through the body.
One aspect is directed to a method of attaching an engine to a wing of an aircraft. The method comprises: attaching a first fitting to a first section of an aft engine mount fitting of a ridgeback fitting; attaching a second fitting to a second section of the aft engine mount fitting of the ridgeback fitting and connecting together the first section and the second section of the ridgeback fitting; attaching a forward engine mount fitting to the ridgeback fitting; attaching the ridgeback fitting to a strut box on a wing of an aircraft; and attaching the engine to the forward engine mount fitting and to the first fitting and the second fitting of the aft engine mount fitting and thereby attaching the engine to the wing of the aircraft.
In another aspect, the method further comprises positioning the forward engine mount fitting at first ends of the first section and the second section and then connecting together the first section and the second section of the ridgeback fitting and connecting the forward engine mount fitting to the ridgeback fitting.
In another aspect, the method further comprises aligning a first section of flanges on the first section with a second section of flanges on the second section and connecting together the first section and the second section and forming a single flange that extends along a length of the ridgeback fitting.
The features, functions and advantages that have been discussed can be achieved independently in various aspects or may be combined in yet other aspects, further details of which can be seen with reference to the following description and the drawings.
The fan 105 of the engine 103 is positioned forward of the ridgeback fitting 20. Air that flows through the fan 105 passes by the ridgeback fitting 20 that is covered by an aerodynamic forward pylon fairing (not illustrated). The ridgeback fitting 20 is shaped to reduce impingement of the air flow on the fan 105. In some examples, the ridgeback fitting 20 is positioned directly behind a center of the fan 105.
In some examples, the body 21 has a tapered shape with a smaller sectional area at the forward end 22 and a larger section area at the rear end 23. This tapered shape provides for transitioning between the strut box that connects to the rear end 23 and the forward engine mount fitting 30 that connects to the forward end 22. The tapered shape also facilitates airflow. In some examples, the taper is consistent along the length from the forward end 22 to the rear end 23.
The body 21 is formed from two sections 51, 52 that abut together and form a joint 53. In some examples, the two sections 51, 52 have a clamshell design that align together. The two sections 51, 52 include exposed edges along an inner side that abut together to form the joint 53. In some examples, each of the sections 51, 52 is substantially equal and forms one-half of the ridgeback fitting 20. In one specific example, the sections 51, 52 are mirror images. In some examples, the sections 51, 52 have different shapes and/or sizes with one of the sections 51, 52 being larger than the other.
An advantage of the body 21 formed by the two sections 51, 52 is the ability to access the interior sides prior to them being connected together. This provides for accessing fasteners 110 that are used to connect one or more of the forward engine mount fitting 30 and aft engine mount fitting 40. This overcomes a current issue with the inability to access these fasteners within an enclosed interior of the strut box (which are often referred to as “blind fasteners”).
In some examples as illustrated in
Flanges 60 extend along one or more sides of the body 21. The flanges 60 are configured to form a structural interface that takes both shear and tensions loads across the joint 53. The flanges 60 are positioned along one or more of the sides of the ridgeback fitting 20. In some examples, flanges 60 are positioned along the top side 24 and the bottom side 25. In some examples, the ridgeback fitting 20 does not include flanges 60.
The flanges 60 include a central flange section 61 and stiffeners 62 that are spaced apart along the flange section 61. The stiffeners 62 extend laterally outward away from the flange section 61 and have a tapering height that decreases away from the flange section 61. The stiffeners 62 structurally support the flange section 61. The flange section 61 includes leading and trailing ends that are tapered to improve structural load distribution. In examples with flanges 60 on two or more of the sides of the ridgeback fitting 20, the flanges 60 can have the same or different configurations. In some examples, the flanges 60 are symmetrical about a centerline that extends along the flange section 61.
In some examples, the flanges 60 are divided between the first section 51 and the second section 52. Each of the sections 51, 52 includes a portion of the flange section 61 and one set of the stiffeners 62. When the sections 51, 52 are abutted together, the opposing flange sections abut together and form a single flange section 61.
The two sections 51, 52 are connected together by fasteners 110. The fasteners 110 extend through the two sections 51, 52 and bridge the joint 53. In one example as illustrated in
An interior space 29 is formed within the ridgeback fitting 20. The two sections 51, 52 can be designed to have various numbers and arrangements of ribs and pocket configurations. The sections 51, 52 are designed to optimize the load distribution in the ridgeback fitting 20 itself when reacting to engine mount interface loads between the engine 103 and the strut box 104.
One or more ribs 70 extend outward from opposing sides and across the interior space 29. The ribs 70 provide strength and stiffness to the ridgeback fitting 20. In some examples, the ribs 70 extend between the opposing lateral sides 26, 27. The ribs 70 are formed from different sections that extend outward from the sides of the different sections 51, 52. When the sections 51, 52 are connected together, the ribs 70 on each of the sections align and abut together.
The interior space 29 also includes a pocket 89 at the rear end 23. The pocket 89 is sized to receive the strut box 104. In some examples, one or more fasteners 110 connect the strut box 104 to the pocket 89 of the ridgeback fitting 20.
The ridgeback fitting 20 is configured to be connected to the aft engine mount fitting 40 which in turn connects to the engine 103. The aft engine mount fitting 40 includes fittings 41 that are mounted to the lateral sides 26, 27 of the ridgeback fitting 20. Fasteners 110 connect the fittings 41 to the ridgeback fitting 20.
The ridgeback fitting 20 can be used to connect a variety of different engines 103 to a wing 102 of an aircraft 100. In some examples, the engines 103 have exposed fan blades. One specific example is an unducted turbofan engine. In other examples, the engine 103 includes ducted fans.
Various types of fasteners 110 are used for connecting the sections 51, 52 and connecting the forward engine mount fitting 30 and/or aft engine mount fitting 40. Examples include but are not limited to rivets, pins, nuts/bolts, and pegs.
By the term “substantially” with reference to amounts or measurement values, it is meant that the recited characteristic, parameter, or value need not be achieved exactly. Rather, deviations or variations, including, for example, tolerances, measurement error, measurement accuracy limitations, and other factors known to those skilled in the art, may occur in amounts that do not preclude the effect that the characteristic was intended to provide.
The present disclosure may be carried out in other ways than those specifically set forth herein without departing from essential characteristics of the invention. The present embodiments are to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.
This application claims priority to U.S. Provisional Patent Application Ser. No. 63/540,434 filed on Sep. 26, 2023, which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63540434 | Sep 2023 | US |