Patent Description:
The integration or connection of an aircraft wing to an aircraft body for composite material designs of aircraft is challenging in terms of satisfying structural strength requirements, providing corrosion prevention, facilitating the building or assembly of the aircraft wing to the aircraft body and meeting requirements for inspection and repairability of the connection between the aircraft wing and the aircraft body. The typical metallic connection architecture between the aft wing spar root fitting and the aircraft body fuselage is difficult to manufacture and often results in peaking loads transferred between a composite spar of the aircraft wing and the composite skin of the aircraft fuselage.

Document <CIT>, according to its abstract, states a trapezoidal panel pin joint for allowing deflection of an aircraft between a fuselage section and a wing section, wherein the pin joint comprises a vertical pin portion, a lug portion, and a clevis portion; wherein at least one vertical flexible tee member is positioned below the pin joint; and wherein the pin joint is coupled to at least two horizontal flexible tee members, such that the pin joint and vertical and horizontal flexible tee members, in combination, release two rotational degrees of freedom.

There is provided an assembly connecting an aircraft wing to an aircraft body, the assembly comprising the aircraft wing, the aircraft body, a panel on the aircraft body, the panel having a panel forward edge, the panel forward edge having a forward edge surface; the panel having a panel bottom, the panel bottom having a panel bottom surface; the panel forward edge surface opposing a rearward edge surface of a rearward extending flange on the aircraft wing; the panel bottom surface opposing a top surface of a rearward extending plate on the aircraft wing; a forward connection connected to the panel and to the rearward extending flange and connecting the panel and the rearward extending flange; the forward connection comprising a forward splice plate, the forward splice plate being engaged in surface engagement with the panel and being connected to the panel; and the forward splice plate being engaged in surface engagement with the rearward extending flange and being connected to the rearward extending flange.

There is provided a method of assembling an aircraft wing to an aircraft body, the method comprising moving the aircraft wing toward the aircraft body; positioning a panel forward edge surface of a panel on the aircraft body opposite a rearward edge surface on a rearward extending flange on the aircraft wing; positioning a panel bottom surface on the panel opposite a top surface on a rearward extending plate on the aircraft wing with there being a gap between the panel bottom surface and the top surface of the rearward extending plate on the aircraft wing; and positioning a plurality of forward splice plates at spatially arranged positions along the panel forward edge surface and along the rearward edge surface of the rearward extending flange; and, connecting the plurality of forward splice plates to the panel and to the rearward extending flange.

Further details can be seen with reference to the following description and drawings.

<FIG> is a representation of a side elevation view of the port side or left side of an aircraft body <NUM> with the port side or left side aircraft wing <NUM> joined to the side of the aircraft body <NUM>. Although the assembly connecting the aircraft wing <NUM> to the aircraft body <NUM> to be described refers to the connection of the left side or port side aircraft wing <NUM> to the aircraft body <NUM>, it should be understood that the concepts of the assembly are equally well applicable to the connection of the starboard side or right side aircraft wing to the aircraft body. The assembly and method of this disclosure for connecting the aircraft wing <NUM> to the aircraft body <NUM> facilitates the building process of integrating and fitting an aft wing spar root of the aircraft wing <NUM> to the fuselage of the aircraft body <NUM>. The assembly allows improved load paths from the aircraft wing <NUM> to the aircraft body <NUM> and thereby reduces the overall weight of the assembly structure. Several features of the assembly enable easy inspection at critical joints between the aircraft wing <NUM> and the aircraft body <NUM>. Improved joints of the assembly allow fay seal application during assembly of the aircraft wing <NUM> to the aircraft body <NUM> for corrosion protection at supporting fay seal surfaces.

Referring to <FIG> shows a representation of the root end or inboard end <NUM> of the aft wing spar <NUM>, or rearward wing spar. <FIG> is a representation of an outboard portion of the fuselage <NUM> and the outboard end <NUM> of the aircraft wheel well to which the root end of the aft wing spar <NUM> represented in <FIG> is joined. As represented in <FIG>, the assembly connecting the aircraft wing <NUM> to the aircraft body <NUM> includes a trap panel or a panel <NUM>. The panel <NUM> is represented in <FIG> as connected to the aircraft fuselage <NUM>. The outboard side of the panel <NUM> is represented in <FIG>.

<FIG> is a representation of the inboard side of the panel <NUM> removed from the fuselage <NUM>. The panel <NUM> is often referred to as a "trap" panel due to its general trapezoidal configuration. The panel <NUM> is typically constructed as one, monolithic piece of aluminum to reduce cost. However, other equivalent materials could be employed in constructing the panel <NUM>. The panel <NUM> has a planar, outboard side surface <NUM> represented in <FIG>, and an opposite, planar, inboard side surface <NUM> represented in <FIG>. A thickness dimension of the panel <NUM> is substantially constant between the outboard side surface <NUM> and the inboard side surface <NUM>. A plurality of outboard stiffener ribs <NUM> arranged in a grid pattern are formed integrally on the outboard side surface <NUM> of the panel <NUM>. A plurality of inboard stiffener ribs <NUM> arranged in a grid pattern are formed integrally on the inboard side surface <NUM> of the panel <NUM>. The stiffener ribs <NUM>, <NUM> add rigidity to the panel <NUM> and strengthen the panel.

The panel <NUM> has a panel forward edge that is directed toward the forward end of the length of the aircraft fuselage. The panel forward edge has a forward edge surface <NUM>. The forward edge surface <NUM> has a thickness dimension that is substantially the same as the thickness dimension of the panel <NUM> between the outboard side surface <NUM> and the inboard side surface <NUM> of the panel.

The panel <NUM> has a top that is oriented toward the top of the aircraft fuselage of the aircraft body <NUM>. A panel top flange <NUM> is integrally connected to the top of the panel <NUM>. The panel top flange <NUM> projects outwardly from the inboard side surface <NUM> of the panel <NUM>, but does not project outwardly from the outboard side surface <NUM> of the panel <NUM>. The panel top flange <NUM> is oriented at a perpendicular orientation or at a right angle relative to the inboard side surface <NUM> of the panel <NUM>. The panel top flange <NUM> has a panel top surface <NUM> or a top flange surface <NUM> that extends along the panel top flange <NUM>. The panel top flange surface <NUM> is generally aligned with the length of the aircraft fuselage.

The panel <NUM> has a bottom that is oriented toward the bottom of the aircraft fuselage of the aircraft body <NUM>. A panel bottom flange <NUM> is integrally connected to the bottom of the panel <NUM>. The panel bottom flange <NUM> projects outwardly from the outboard side surface <NUM> of the panel <NUM> and from the inboard side surface <NUM> of the panel <NUM>. The panel bottom flange <NUM> is oriented at an angle relative to the outboard side surface <NUM> and the inboard side surface <NUM> of the panel <NUM>. The panel bottom flange <NUM> has a panel bottom surface or bottom flange surface <NUM> that extends along the panel bottom flange <NUM>. The panel bottom flange surface <NUM> is generally aligned with the length of the aircraft fuselage.

The panel <NUM> has a rearward end that is directed toward the rearward end of the length of the aircraft fuselage. A panel rearward flange <NUM> is integrally connected to the rearward end of the panel <NUM>. The panel rearward flange <NUM> extends between the panel top flange <NUM> and the panel bottom flange <NUM>. The panel rearward flange <NUM> is continuous with the panel top flange <NUM> and the panel bottom flange <NUM>. The panel rearward flange <NUM> projects outwardly from the outboard side surface <NUM> of the panel <NUM> and from the inboard side surface <NUM> of the panel <NUM>. The panel rearward flange <NUM> is oriented at an angle relative to the outboard side surface <NUM> of the panel <NUM> and the inboard side surface <NUM> of the panel <NUM>. The panel rearward flange <NUM> has a panel rearward surface <NUM> or a rearward flange surface <NUM> that extends along the panel rearward flange <NUM>.

The assembly connecting the aircraft wing <NUM> to the aircraft body <NUM> also includes a terminal fitting <NUM> or a wing rear spar terminal fitting <NUM>. The terminal fitting <NUM> is represented in <FIG> as attached to the aft wing spar <NUM> at the inboard, root end of the aircraft wing <NUM>. The terminal fitting <NUM> is represented in <FIG> as removed from the aft wing spar <NUM>. The terminal fitting <NUM> is constructed of a strong metal, for example titanium. Other equivalent materials could be used to construct the terminal fitting <NUM>. Composite materials could also be used to construct the terminal fitting <NUM>.

The terminal fitting <NUM> has a rearward extending flange, or aft flange <NUM>. With the terminal fitting <NUM> connected to the aircraft wing <NUM>, the aft flange <NUM> extends in a rearward direction relative to the aircraft body <NUM>. The terminal fitting <NUM> also includes an outboard flange <NUM>. The outboard flange <NUM> extends outwardly or in an outboard direction from the aft flange <NUM>. As represented in <FIG>, the outboard flange <NUM> is secured to the inboard end of the aft wing spar <NUM> by fasteners, or by other equivalent means. The terminal fitting <NUM> also includes an inboard flange <NUM>. The inboard flange extends inwardly or in an inboard direction from the aft flange <NUM>. When the aircraft wing <NUM> is secured to the aircraft body <NUM>, the inboard flange <NUM> is secured to the aircraft fuselage. In this disclosure, when the aircraft wing <NUM> is secured to the aircraft body <NUM>, the inboard flange <NUM> of the terminal fitting <NUM> is secured by fasteners or by other equivalent means to an aft spar of the center wing box of the aircraft fuselage. As represented in <FIG>, <FIG>, <FIG> and <FIG>, the aft flange <NUM> of the terminal fitting <NUM> has a planar, inboard side surface <NUM>. As represented in <FIG>, the aft flange <NUM> of the terminal fitting <NUM> has a planar, outboard side surface <NUM>. A thickness dimension of the aft flange <NUM> is substantially constant between the outboard side surface <NUM> and the inboard side surface <NUM> of the aft flange <NUM>.

The aft flange <NUM> has a flange rearward edge that is directed toward the rearward end of the length of the aircraft fuselage. The flange rearward edge has a rearward edge surface <NUM>. The aft flange rearward edge surface <NUM> has a thickness dimension that is substantially the same as the thickness dimension of the aft flange <NUM> between the outboard side surface <NUM> and the inboard side surface <NUM> of the aft flange <NUM>.

The assembly also includes a side fitting <NUM> or a rear spar side fitting <NUM>. The side fitting <NUM> is represented secured by fasteners or other equivalent means to the aircraft fuselage in <FIG> and <FIG>. <FIG> and <FIG> represent the side fitting <NUM> secured by fasteners or other equivalent means to an aft spar <NUM> of the center wing box. <FIG> is a representation of the side fitting <NUM> removed from the aft spar <NUM> of the center wing box of the aircraft fuselage. As represented in <FIG>, the side fitting <NUM> has a base <NUM> that is configured or shaped to fit in a vertical orientation flat against the aft spar <NUM> of the center wing box. A vertically oriented inboard flange <NUM> and a vertically oriented outboard flange <NUM> extend rearwardly from opposite sides of the side fitting base <NUM>. The side fitting <NUM> has a stiffener flange <NUM> or a stiffener <NUM> that extends rearwardly from a top of the base <NUM>. The stiffener flange <NUM> is horizontally oriented relative to the base <NUM>. As represented in <FIG>, <FIG>, the side fitting stiffener flange <NUM> or side fitting stiffener <NUM> aligns with and is positioned in a same plane as a horizontal flange of the aircraft body. As represented in <FIG>, the side fitting stiffener <NUM> is aligned with and positioned in a same horizontal plane as a longeron flange <NUM> of a wheel well longeron <NUM>.

As represented in <FIG>, a splice plate <NUM> is connected by fasteners to both the stiffener flange <NUM> of the side fitting <NUM> and to the wheel well longeron flange <NUM>. The splice plate <NUM> connected between the side fitting <NUM> and the wheel well longeron flange <NUM> provides a second, separate load path between the aircraft wing <NUM> and the fuselage of the aircraft body <NUM>.

The assembly also includes a main landing gear up-lock fitting <NUM> or an up-lock fitting <NUM> on the trap panel <NUM>. As represented in <FIG> and <FIG>, the up-lock fitting <NUM> is integrally formed into the reinforcing inboard stiffener ribs <NUM> that are integral with the inboard side surface <NUM> of the trap panel <NUM>. A bushing (not shown) connects a main landing gear (not shown) to the up-lock fitting <NUM>. The up-lock fitting <NUM> being integrally formed with the trap panel <NUM> provides a direct load path from the main landing gear into the body of the aircraft and reduces the number of parts required for the connection of the main landing gear to the aircraft body <NUM>, thereby saving weight and improving integration space.

Also represented in <FIG>, <FIG> is a lower plate <NUM> or lower splice plate <NUM> connected to the inboard end of the aircraft wing <NUM> below the aft flange <NUM>. <FIG> is a representation of a plan view of the lower splice plate <NUM> removed from the aircraft wing <NUM>. The lower plate <NUM> is constructed as one, monolithic piece of titanium. However, other equivalent materials could be employed in constructing the lower plate <NUM>. <FIG> is a representation of a plan view of the top of the lower plate <NUM>. As represented in <FIG>, <FIG>, <FIG>, the lower plate <NUM> has a configuration with a wide base portion <NUM> and a more narrow, rearward extending portion <NUM> or rearward portion <NUM>. The base portion <NUM> of the lower plate <NUM> is secured to the bottom of the aft wing spar <NUM> and the bottom of the terminal fitting <NUM>. The rearward extending portion <NUM> of the lower plate <NUM> projects rearwardly from the connection of the base portion <NUM> to the aft wing spar <NUM> and the terminal fitting <NUM>. The rearward extending portion <NUM> of the lower plate <NUM> has a top surface <NUM> that extends rearwardly from beneath the aft wing spar <NUM> and the terminal fitting <NUM>.

Prior to assembling the aircraft wing <NUM> to the aircraft body <NUM>, the trap panel <NUM> is connected to the fuselage <NUM> of the aircraft body <NUM> as represented in <FIG>, <FIG>. The panel <NUM> is positioned relative to the fuselage <NUM> with the panel top flange surface <NUM> engaging against a bottom surface of the fuselage <NUM>. An upper connection connects the panel <NUM> to the bottom surface of the fuselage <NUM> or to the bottom surface of the aircraft body <NUM>. The upper connection is comprised of at least one upper splice plate <NUM>, and preferably a plurality of upper splice plates <NUM>. As represented in <FIG> and <FIG>, the upper splice plates <NUM> are generally thin, flat pieces of material such as a composite material or other equivalent type of material. The upper splice plates <NUM> represented in <FIG> and <FIG> have general, rectangular configurations. However, the upper splice plates <NUM> could have other equivalent configurations that enable the upper splice plates <NUM> to lay flat in surface engagement against the outboard side surface <NUM> of the panel <NUM> and the outboard surface of the fuselage <NUM> as represented in <FIG> and <FIG>. The upper splice plates <NUM> are spatially positioned along the panel top surface or the panel top flange <NUM> and along the outboard surface of the fuselage <NUM>. The upper splice plate or plurality of upper splice plates <NUM> are engaged in surface engagement with the outboard side surface <NUM> of the panel <NUM> and are connected to the panel <NUM> by fasteners such as nut and bolt fasteners or other equivalent types of fasteners, and the upper splice plate or plurality of upper splice plates <NUM> are engaged in surface engagement with the fuselage <NUM> of the aircraft body and are connected to the fuselage <NUM> by fasteners such as nut and bolt fasteners, or other equivalent types of fasteners. The upper connection provided by the upper splice plate or upper splice plates <NUM> connects the panel <NUM> to the fuselage <NUM> of the aircraft body <NUM>, or connects the panel <NUM> to the bottom surface of the fuselage <NUM> of the aircraft body <NUM>.

With the upper splice plates <NUM> secured to the outboard side surface <NUM> of the panel <NUM>, the panel <NUM> has exposed surface areas <NUM> on the panel outboard side surface <NUM>. The exposed surface areas <NUM> are adjacent the panel top flange <NUM> and between adjacent upper splice plates <NUM> of the plurality of upper splice plates. The panel exposed surfaces <NUM> provide means for inspection of the outboard side surface <NUM> of the panel <NUM> for signs of panel fatigue, for example panel cracks at the panel exposed surface areas <NUM>.

In assembling the aircraft wing <NUM> to the aircraft body <NUM>, the assembled aircraft wing <NUM> is moved toward the aircraft body <NUM>. The root end or inboard end of the aft wing spar <NUM> of the aircraft wing <NUM> is moved toward the outboard surface of the fuselage <NUM> and the outboard end of the wheel well <NUM>. The movement is continued until the root end <NUM> or the inboard end of the aft wing spar <NUM> of the aircraft wing <NUM> comes into contact with the outboard surface of the fuselage <NUM>. Alternatively, the aircraft body <NUM> and aircraft wing <NUM> are aligned by moving the wing <NUM> inboard until an alignment criteria with the fuselage or aircraft body <NUM> is met (such as the terminal fitting aft flange <NUM> aligning with the panel forward edge surface <NUM>).

The movement of the aircraft wing <NUM> to the aircraft body <NUM> positions the trap panel forward edge surface <NUM> opposing the rearward edge surface <NUM> of the rearward extending aft flange <NUM> as represented in <FIG>. The movement of the aircraft wing <NUM> to the aircraft body <NUM> also positions the panel bottom flange surface <NUM> opposing the top surface <NUM> of the rearward extending portion <NUM> of the lower splice plate <NUM>.

There is a gap between the panel bottom flange surface <NUM> and the top surface <NUM> of the rearward extending portion <NUM> of the lower splice plate <NUM>. A cross-section view of the gap is represented in <FIG>. The gap has an inboard portion <NUM> of the gap and an outboard portion <NUM> of the gap on opposite sides of the gap. As represented in <FIG>, the inboard portion of the gap <NUM> tapers as the inboard portion of the gap <NUM> extends into the gap. The outboard portion of the gap <NUM> also tapers as the outboard portion of the gap <NUM> extends into the gap.

With the movement of the aircraft wing <NUM> to the aircraft body <NUM> positioning the panel bottom flange surface <NUM> opposite the top surface <NUM> of the rearward extending portion <NUM> of the lower splice plate <NUM> as represented in <FIG>, and <FIG>, a shim is inserted into the gap between the panel bottom flange surface <NUM> and the top surface <NUM> of the rearward extending portion <NUM> of the lower splice plate <NUM>. The shim is comprised of an inboard shim <NUM> and a separate outboard shim <NUM>. The inboard shim <NUM> is inserted into the inboard portion of the gap <NUM> and the outboard shim <NUM> is inserted into the outboard portion of the gap <NUM>. The tapered cross-section configurations of the inboard portion of the gap <NUM> and the outboard portion of the gap <NUM> facilitate the insertions of the inboard shim <NUM> and the outboard shim <NUM> into their respective gaps. After installation, there is a gap between the inboard shim <NUM> and the outboard shim <NUM> that allows a squeeze out of the fay sealant. The taper of the shims <NUM>, <NUM> prevents total scraping off of the fay sealant as the shims are inserted into the gaps. The inboard shim <NUM> and the outboard shim <NUM> provide fay seals between the aluminum of the trap panel <NUM> and the titanium of the lower splice plate <NUM>.

There is a forward connection connected to the panel <NUM> and connected to the rearward extending aft flange <NUM> on the aircraft wing <NUM>. The forward connection is represented in <FIG> and <FIG>. The forward connection connects the panel <NUM> to the rearward extending aft flange <NUM>. The forward connection is comprised of a forward splice plate, or a plurality of forward splice plates. <FIG> represents a single, large forward splice plate <NUM> connecting the panel <NUM> to the rearward extending flange <NUM>. The large forward splice plate <NUM> is secured to the panel outboard side surface <NUM> and is secured to the rearward extending flange outboard side surface <NUM>. <FIG> represents a plurality of small forward splice plates <NUM> connecting the panel <NUM> to the rearward extending flange <NUM>. The plurality of small forward splice plates <NUM> are secured to the panel inboard side surface <NUM> and are secured to the reward extending flange inboard side surface <NUM>. It should be understood that a large splice plate <NUM> could replace the small splice plates <NUM>, and that the small splice plates <NUM> could replace the large splice plate <NUM>. In <FIG>, the forward connection splice plates <NUM>, <NUM> are engaged in surface engagement with the panel <NUM> and are connected to the panel by fasteners, such as nut and bolt fasteners, and are engaged in surface engagement with the rearward extending aft flange <NUM> and are connected to the rearward extending flange <NUM> by fasteners, such as nut and bolt fasteners. In <FIG>, the plurality of small splice plates <NUM> are spatially arranged at positions along the forward edge surface <NUM> of the panel <NUM> and are spatially arranged at positions along the rearward edge surface <NUM> of the rearward extending aft flange <NUM>.

Adjacent small splice plates <NUM> of the plurality of forward splice plates connected to the panel inboard side surface <NUM> as represented in <FIG> leave exposed surface areas <NUM> on the panel inboard side surface <NUM> adjacent the panel forward edge surface <NUM>. The panel exposed surface areas <NUM> provide means for inspection of the panel inboard side surface <NUM> for signs of fatigue, for example the formation of cracks at the panel exposed surface areas <NUM>.

The assembly and method of this disclosure for connecting the aircraft wing <NUM> to the aircraft body <NUM> facilitates the building process of integrating and fitting the inboard end of the aft wing spar <NUM> of the aircraft wing <NUM> to the fuselage <NUM> of the aircraft body <NUM>. The assembly provides structural strength to the connection between the aircraft wing <NUM> and the aircraft body <NUM>. The assembly allows an improved load path from the aircraft wing <NUM> to the aircraft body <NUM> provided by the splice plates <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, which also reduce the overall weight of the assembly structure. The use of the splice plates <NUM>, <NUM>, <NUM>, <NUM>, <NUM> also enable easy inspection at critical joints between the aircraft wing <NUM> and the aircraft body <NUM>. The improved joints of the assembly allow fay seal application in the gap <NUM>, <NUM> between the panel bottom flange surface <NUM> and the lower splice plate top surface <NUM>, providing corrosion protection.

Claim 1:
An assembly connecting an aircraft wing (<NUM>) to an aircraft body (<NUM>), the assembly comprising:
the aircraft wing (<NUM>); a rearward extending flange (<NUM>) on the aircraft wing, the rearward extending flange having a rearward edge surface; a rearward extending plate (<NUM>, <NUM>) on the aircraft wing, the rearward extending plate having a top surface;
the aircraft body (<NUM>);
a panel (<NUM>) on the aircraft body (<NUM>), the panel having a panel forward edge, the panel forward edge having a forward edge surface (<NUM>);
the panel having a panel bottom, the panel bottom having a panel bottom surface (<NUM>);
the panel forward edge surface (<NUM>) opposing the rearward edge surface of the rearward extending flange (<NUM>) on the aircraft wing (<NUM>);
the panel bottom surface (<NUM>) opposing the top surface of the rearward extending plate on the aircraft wing (<NUM>);
a forward connection connected to the panel and to the rearward extending flange (<NUM>) and connecting the panel (<NUM>) and the rearward extending flange (<NUM>);
the forward connection comprising a forward splice plate (<NUM>, <NUM>), the forward splice plate (<NUM>, <NUM>) being engaged in surface engagement with the panel (<NUM>) and being connected to the panel (<NUM>); and,
the forward splice plate (<NUM>, <NUM>) being engaged in surface engagement with the rearward extending flange and being connected to the rearward extending flange.