Composite fabric spar with staggered capped plies

Abstract

A composite aircraft wing construction includes a wing spar having a web composed solely of prepreg fabric and having first and second spar caps projecting at an angle from opposite edges of the web, wherein the first and second spar caps are composed of staggered and alternating portions of prepreg fabric and unidirectional prepreg tape of the web.

Description

Technical Field

[0001] The present disclosure relates to composite aircraft wing constructions. In particular, the present disclosure relates to a spar having a web constructed solely of prepreg fabric and having first and second spar caps projecting at an angle from opposite edges of the web, wherein the first and second spar caps are constructed from alternating portions of prepreg fabric and unidirectional prepreg tape of the web. Background Art

[0002] Figure 1 1 is a schematic diagram of a typical configuration of the internal structure of an aircraft wing 12. The internal structure of the wing 12 is basically composed of a framework of spars 14 and ribs 16 contained within the outer skin 18 of the wing, such as Figure 1 In the current aircraft structure, the wing spar 14 and the wing rib 16 are made of composite materials.

[0003] The spar 14 extends the length of the wing from the fuselage end or root end 22 of the wing 12 to the tip end 24 of the wing. The spar 14 provides the wing 12 with most of its strength.

[0004] The spar 14 is typically constructed from pre-impregnated composite tapes. Construction of the spar 14 is typically an automated process where a machine rapidly lays down multiple pre-impregnated composite tapes on the surface of a layup tool or curing tool.

[0005] Figure 2 is a schematic diagram of a cross-sectional view of a typical layup tool or curing tool 26. The tool 26 has dimensions that substantially correspond to the dimensions of the spar 14 to be constructed on the tool. Figure 2 Only the cross-sectional dimensions of the tool 26 are shown in FIG. 1 , but it should be understood that the tool 26 will have a length dimension that corresponds to the length dimension of the spar 14 to be constructed on the tool.

[0006] Figure 3 2 is an illustration of the manner in which prepreg tapes or strips are laid down by an automated fiber placement (AFP) machine onto the surface of a layup tool or curing tool 26. The spar 14 is constructed on the tool 26 by laying down layers or plies of prepreg tapes 28 side by side at a 0° angle along the length of the tool 26, thereby forming a full longitudinal layer of composite material along the full length of the spar 14. Figure 3 As shown, the AFP machine also lays down an additional layer of prepreg tape 30 side by side at -45° on top of the prepreg tape 28 oriented at 0°. Figure 3 2, but the AFP machine will also lay down additional layers of prepreg tape side by side at a +45° orientation and a 90° orientation relative to the length of the tool 26. Several layers of prepreg tape plies may be laid down on the tool 26 when constructing the spar 14.

[0007] Composite aircraft wing spars constructed in the manner described above are susceptible to wrinkles in the layers of prepreg tape laid down on the layup tool or curing tool 26. This is due to the length of the tool 26 having a variation in geometry along the length of the tool, which is associated with a variation in the geometry of the spar 14 formed on the tool. In a typical construction of the spar 14, the width dimension of the spar 14 tapers and narrows as it extends from the fuselage end or root end 22 of the spar to the tip end 24 of the spar. In addition, the height dimension of the spar 14 typically tapers and decreases as the spar 14 extends from the fuselage end 22 of the spar to the tip end 24 of the spar. Still further, the spar 14 may have a curved portion or one or more angled portions as the spar 14 extends from the fuselage end 22 to the tip end 24 of the spar. These variations in the geometry of the spar 14 along the length of the spar often result in wrinkles forming between the layers or plies of prepreg tape that make up the spar construction. Wrinkles formed between layers of prepreg tape of the spar 14 may result in significant strength and stiffness reductions in the spar 14. Currently, solutions for overcoming the strength and stiffness reductions in the construction of the spar 14 caused by wrinkles are time consuming and costly. Summary of the invention

[0008] The aircraft wing constructions and in particular aircraft wing spar constructions of the present disclosure substantially eliminate the formation of wrinkles as the composite plies or layers are laid up on a layup tool or curing tool when constructing the aircraft wing spar of the present disclosure.

[0009] The spar of the present disclosure has a length dimension extending between a fuselage end or root end of the spar and an opposite tip end of the spar. The spar has a C-shaped channel cross-sectional configuration along its length dimension.

[0010] The C-channel cross-section configuration of the spar provides the spar with a web at a central portion of the spar. The web has a height dimension between a top edge or top side of the web and an opposite bottom edge or bottom side of the web. The web has a length dimension between a fuselage end of the spar and an opposite tip end of the spar. The web also has a thickness dimension between a first side surface of the web and an opposite second side surface of the web.

[0011] The C-channel cross-sectional configuration of the spar also provides the spar with a first spar cap on the top edge of the web. The first spar cap has a length dimension extending along the top edge of the web between the fuselage end of the spar and the tip of the spar. The first spar cap also has a width dimension protruding from the top edge of the web, and a thickness dimension between a top surface of the first spar cap and an opposite bottom surface of the first spar cap.

[0012] The C-channel cross-sectional configuration of the spar also provides the spar with a second spar cap on the bottom edge of the web. The second spar cap has a length dimension extending along the bottom edge of the web between the fuselage end of the spar and the tip of the spar. The second spar cap also has a width dimension protruding from the bottom edge of the web, and a thickness dimension between a top surface of the second spar cap and an opposite bottom surface of the second spar cap.

[0013] The web of the spar is constructed from layers or plies of prepreg fabric. The web is constructed solely from prepreg fabric.

[0014] The first spar cap is composed of portions of the prepreg fabric of the web and the first prepreg tape. The first prepreg tape is a unidirectional tape in which the composite fibers are oriented along the length direction of the spar. The portions of the prepreg fabric of the web and the first prepreg tape constituting the first spar cap are interleaved with portions of the prepreg fabric of the web and the first prepreg tape arranged in alternating layers.

[0015] The portion of the prepreg fabric constituting the web of the first spar cap extends through the bend as the portion of the prepreg fabric extends from the web to the first spar cap. The bend orients the first spar cap at an angle relative to the web. The first prepreg tape constituting the first spar cap is spaced from the bend by at least 0.25 inches.

[0016] The second spar cap is composed of parts of the prepreg fabric of the web and the second prepreg tape. The second prepreg tape is a unidirectional tape in which the composite fibers are oriented along the length direction of the spar. The parts of the prepreg fabric and the second prepreg tape of the web constituting the second spar cap are interleaved with the parts of the prepreg fabric and the second prepreg tape of the web arranged in alternating layers.

[0017] The portion of the prepreg fabric constituting the web of the second spar cap extends through the bend as the portion of the prepreg fabric extends from the web to the second spar cap. The bend orients the second spar cap at an angle relative to the web. The second prepreg tape constituting the second spar cap is spaced from the bend by at least 0.25 inches.

[0018] The construction of the spar of the present disclosure eliminates prepreg tape from the web and the bends at the top and bottom edges of the web that connect the web to the first and second spar caps, respectively. This eliminates prepreg tape from areas of the spar that would form wrinkles in the tape. The prepreg fabric of the spar is more easily formed without wrinkles over the complex surfaces of the web and the bends at the top and bottom edges of the web. The unidirectional prepreg tapes that are partially interleaved with the prepreg fabric in the first and second spar caps improve the stiffness of the spar in the spanwise direction or along the length dimension of the spar, resulting in a structurally more efficient design. The spar web constructed of 100% prepreg fabric resists shear loads. The spar caps constructed as a mixture of prepreg fabric and prepreg tapes resist bending loads.

[0019] The features, functions, and advantages that have been discussed can be achieved independently in various embodiments or may be combined in yet other embodiments further details of which can be seen with reference to the following description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic diagram of the internal structure of a prior art aircraft wing including a wing spar and a wing rib frame.

[0021] Figure 2 is a schematic diagram of a prior art method of laying down a prepreg tape on a layup tool or a curing tool.

[0022] Figure 3 is a schematic diagram of a prior art method of laying up prepreg tapes in overlapping layers or plies in constructing a prior art aircraft wing spar.

[0023] Figure 4 is a schematic diagram of an aircraft wing configuration including an aircraft wing spar of the present disclosure.

[0024] Figure 5 yes Figure 4 A schematic diagram of a cross-section of an aircraft wing spar of the present disclosure is shown in FIG. DETAILED DESCRIPTION

[0025] Figure 4 is a schematic diagram of a perspective view of the internal structure of an aircraft wing structure 32 employing an aircraft wing spar 34 of the present disclosure. Figure 4 Only one aircraft wing spar 34 is shown in FIG. 3 , but it will be appreciated that an aircraft wing may be constructed using a plurality of aircraft wing spars 34 of the type to be described herein.

[0026] like Figure 4 As shown, an aircraft wing spar 34 extends through the length of the interior of an aircraft wing 32 between a fuselage end or root end 36 of the spar 34 and a tip end 38 of the spar. As the spar 34 extends through the interior of the wing 32, it intersects with a plurality of rib structures 42 in the interior of the wing, as is conventional. As will be described in greater detail herein, the aircraft wing spar 34 is constructed entirely of composite materials.

[0027] The spar 34 has a length dimension extending between a fuselage end 36 of the spar and an opposite tip 38 of the spar. The spar 34 has a C-shaped channel cross-sectional configuration along its entire length dimension. The configuration of the spar 34 to be described herein may be used in spars having other cross-sectional configurations.

[0028] The C-shaped channel cross-sectional configuration of the spar 34 provides the spar with a web 44 at a central portion of the spar. The web 44 has an elongated rectangular configuration having a height dimension between a top edge or top side 46 of the web 44 and an opposite bottom edge or bottom side 48 of the web. The web 44 may have a plurality of Figure 4 . For example, the web 44 may have an elongated tapered configuration as the web extends from the fuselage end 36 of the web to the tip 38 of the web. The web 44 has a length dimension between the fuselage end 36 of the spar 34 (which forms the fuselage end 36 of the web 44) and the opposite tip 38 of the spar 34 (which forms the tip 38 of the web 44). The web 44 also has a thickness dimension between a first side surface 52 of the web and an opposite second side surface 54 of the web.

[0029] The C-channel cross-sectional configuration of the spar 34 also provides the spar with a first spar cap 56 on the top edge 46 of the web 44 . Figure 4 The first spar cap 56 shown in has an elongated rectangular configuration. The first spar cap 56 may have other equivalent configurations. For example, when the first spar cap 56 extends from the fuselage end 36 of the spar 34 to the tip 38 of the spar, the first spar cap 56 may have a tapered configuration. The first spar cap 56 has a length dimension extending along the top edge 46 of the web 44 between the fuselage end 36 of the spar 34 (which forms the fuselage end 36 of the first spar cap 56) to the tip 38 of the spar 34 (which forms the tip 38 of the first spar cap 56). The first spar cap 56 also has a width dimension that protrudes from the top edge 46 of the web 44 and extends therefrom to the rear edge 58 of the first spar cap 56. Figure 4 As shown, the width dimension of the first spar cap 56 extends from the top edge 46 of the web 44 at a right angle relative to the web 44. The width dimension of the first spar cap 56 may extend from the top edge 46 of the web 44 at other angular orientations. The first spar cap 56 also has a thickness dimension between a top surface 62 of the first spar cap and an opposing bottom surface 64 of the first spar cap.

[0030] The C-channel cross-sectional configuration of the spar 34 also provides the spar with a second spar cap 66 on the bottom edge 48 of the web 44. The second spar cap 66 has an elongated rectangular configuration extending from the fuselage end 36 of the spar 34 to the tip 38 of the spar. The second spar cap 66 may have other equivalent configurations. For example, when the second spar cap 66 extends from the fuselage end 36 of the spar 34 to the tip 38 of the spar, the second spar cap 66 may have a tapered configuration. The second spar cap 66 has a length dimension extending along the bottom edge 48 of the web 44 between the fuselage end 36 of the spar 34 (which forms the fuselage end 36 of the second spar cap 66) to the tip 38 of the spar 34 (which forms the tip 38 of the second spar cap 66). The second spar cap 66 has a width dimension protruding from the bottom edge 48 of the web 44 and extending therefrom to the rear edge 68 of the second spar cap 66. The width dimension of the second spar cap 66 protrudes from the bottom edge 48 of the web 44 at a right angle relative to the web 44. The width dimension of the second spar cap 66 may protrude from the bottom edge 48 of the web 44 at other angular orientations. The second spar cap 66 also has a thickness dimension between a top surface 72 of the second spar cap 66 and an opposing bottom surface 74 of the second spar cap 66.

[0031] Figure 5 yes Figure 4 A schematic diagram of a cross section of the configuration of an aircraft wing spar 34 is shown in FIG. Figure 5 In the center is an illustration of a cross-section of a layup tool or curing tool 76 used to construct an aircraft wing spar 34. Figure 5 As shown, the laying tool 76 has a C-shaped channel cross-section configuration that has been rotated 90° clockwise. Figure 5 The configuration of the laying tool 76 shown in FIG. extends the entire length of the tool. The length of the laying tool 76 corresponds to the length of the aircraft wing spar 34 to be constructed on the tool. Figure 5 As shown, a first composite prepreg fabric layer 82 is laid up on the layup tool 76. The first prepreg fabric layer 82 extends completely over a top surface 84 of the tool 76, over a first side surface 86 of the tool 76, and over a second side surface 88 of the tool 76. The first prepreg fabric layer 82 also extends along the entire length dimension of the tool 76.

[0032] A first prepreg tape 92 is laid over the portion of the first prepreg fabric layer 82 that is located on the first side surface 86 of the tool. The first prepreg tape 92 has a length dimension that extends the entire length dimension of the first prepreg fabric layer 82 and the entire length dimension of the tool 76. The first prepreg tape 92 is a unidirectional tape with composite fibers oriented along the length dimension of the first prepreg fabric layer 82 and the length dimension of the tool 76.

[0033] A second prepreg tape 94 is then laid over the portion of the first prepreg fabric layer 82 that covers the second side surface 88 of the tool 76. The second prepreg tape 94 has a length dimension that extends the entire length dimension of the first prepreg fabric layer and the entire length dimension of the tool 76. The second prepreg tape 94 is a unidirectional tape with composite fibers oriented along the length dimension of the first prepreg fabric layer 82 and the length dimension of the tool 76.

[0034] Second prepreg fabric layer 96 is then laid over first prepreg fabric layer 82, first prepreg tape 92, and second prepreg tape 94. Second prepreg fabric layer 96 has a width dimension that extends completely across first prepreg fabric layer 82 on top surface 84 of tool 76, across first prepreg tape 92 on first side surface 86 of tool 76, and across second prepreg tape 94 on second side surface 88 of tool 76. Second prepreg fabric layer 96 has a length dimension that extends completely across the length dimension of first prepreg fabric layer 82 and the length dimension of tool 76.

[0035] Another first prepreg tape 98 is then laid over the portion of the second prepreg fabric layer 96 extending over the first prepreg tape 92, which is located over the portion of the first prepreg fabric layer 82 extending over the first side surface 86 of the tool 76. Another first prepreg tape 98 has a width dimension that is substantially the same as the width dimension of the first prepreg tape 92. Another first prepreg tape 98 also has a length dimension that is substantially the same as the length dimensions of the second prepreg fabric layer 96, the first prepreg tape 92, the first prepreg fabric layer 82, and the tool 76. Another first prepreg tape 98 is a unidirectional tape with composite fibers oriented along the length dimension of the second prepreg fabric layer 96 and the length dimension of the tool 76.

[0036] Another second prepreg tape 102 is then laid over the portion of the second prepreg fabric layer 96 extending over the second prepreg tape 94, which is located over the portion of the first prepreg fabric layer 82 extending over the second side surface 88 of the tool 76. Another second prepreg tape 102 has a width dimension that is substantially the same as the width dimension of the second prepreg tape 94. Another second prepreg tape 102 has a length dimension that is substantially the same as the length dimensions of the second prepreg fabric layer 96, the second prepreg tape 94, the first prepreg fabric layer 82, and the length dimension of the tool 76. Another second prepreg tape 102 is a unidirectional tape with composite fibers oriented along the length dimension of the second prepreg fabric layer 96 and the length dimension of the tool 76.

[0037] A third prepreg fabric layer 104 is then laid over the second prepreg fabric layer 96, the other first prepreg tape 98, and the other second prepreg tape 102. The third prepreg fabric layer 96 has a width dimension that completely covers the second prepreg fabric layer 96, the other first prepreg tape 98, and the other second prepreg tape 102. The third prepreg fabric layer 104 also has a length dimension that is substantially the same as the length dimensions of the second prepreg fabric layer 96, the other first prepreg tape 98, the other second prepreg tape 102, and the length dimension of the tool 76.

[0038] The spar 34 described above is composed of the first prepreg fabric layer 82, the first prepreg tape 92, the second prepreg tape 94, the second prepreg fabric layer 96, another first prepreg tape 98, another second prepreg tape 102, and the third prepreg fabric layer 104. This is only one example of the construction of the spar 34. Depending on the loads to be experienced by the spar 34 in use of the aircraft configured with the spar, the number of prepreg fabric layers and prepreg tapes may be changed according to the loads to be experienced on the wing configured with the spar.

[0039] After layup, the prepreg fabric layers, first prepreg tape and second prepreg tape are vacuum bagged, positioned in an autoclave and subjected to a cure cycle that forms the aircraft wing spar 34. The spar 34 is then cooled and trimmed to complete the construction of the spar.

[0040] For an aircraft wing spar 34 constructed as described above, the central web 44 of the spar 34 is constructed from and consists of prepreg fabric layers or plies 82, 96, 104. The central web 44 is constructed from and consists of only prepreg fabric.

[0041] The first spar cap 56 is comprised of portions of the prepreg fabric layers 82, 96, 104 of the web 44 and the first prepreg tapes 92, 98. The first prepreg tapes 92, 98 are unidirectional tapes in which the composite fibers are oriented along the length dimension of the spar 34. The portions of the prepreg fabric layers 82, 96, 104 of the web 44 and the first prepreg tapes 92, 98 that comprise the first spar cap 56 are interleaved with portions of the prepreg fabric layers 82, 96, 104 of the web 44 and the first prepreg tapes 92, 98 that are arranged in alternating layers.

[0042] The portions of the prepreg fabric layers 82, 96, 104 of the web 44 that comprise the first spar cap 56 extend through the bend at the top edge or top edge 46 of the web 44 as the portions of the prepreg fabric extend from the web 44 to the first spar cap 56. The bend at the top edge or top edge 46 of the web 44 orients the first spar cap 56 at an angle relative to the web 44. The first prepreg tapes 92, 98 that comprise the first spar cap 56 are spaced apart from the bend at the top edge or top edge 46 of the web 44 by at least 0.25 inches from the bend.

[0043] The second spar cap 66 is constructed from portions of the prepreg fabric layers 82, 96, 104 and second prepreg tapes 94, 102 of the web 44. The second prepreg tapes 94, 102 are unidirectional tapes in which composite fibers are oriented along the length dimension of the spar 34. The portions of the prepreg fabric layers 82, 96, 104 and second prepreg tapes 94, 102 of the web 44 that make up the second spar cap 66 are interleaved with portions of the prepreg fabric layers 82, 96, 104 and second prepreg tapes 94, 102 of the web 44 that are arranged in alternating layers.

[0044] As portions of the prepreg fabric layers 82, 96, 104 extend from the web 44 to the second spar cap 66, the portions of the prepreg fabric layers 82, 96, 104 of the web 44 that comprise the second spar cap 66 extend through a bend at the bottom edge or bottom edge 48 of the web 44. The bend at the bottom edge or bottom edge 48 of the web 44 orients the second spar cap 66 at an angle relative to the web 44. The second prepreg tapes 94, 102 that comprise the second spar cap 66 are spaced apart from the bend at the bottom edge or bottom edge 48 of the web 44 by at least 0.25 inches from the bend.

[0045] The above-described construction of the spar 34 eliminates prepreg tape from the web 44 and bends at the top edge or top edge 46 of the web 44 and the bottom edge or bottom edge 48 of the web 44 that connect the web 44 to the first spar cap 56 and the second spar cap 66, respectively. This eliminates prepreg tape from areas of the spar 34 that would form wrinkles in the tape. The prepreg fabric layers 82, 96, 104 are more easily formed without wrinkles on the complex surface of the web 44 and the bends at the top edge or top edge 46 and the bottom edge or bottom edge 48 of the web 44. The unidirectional prepreg tapes 92, 98 that are interleaved with portions of the prepreg fabric layers 82, 96, 104 in the first spar cap 56 and the unidirectional prepreg tapes 94, 102 that are interleaved with portions of the prepreg fabric layers 82, 96, 104 in the second spar cap 66 improve the stiffness of the spar 34 in the spanwise direction or along the length dimension of the spar, resulting in a structurally more efficient design. The spar web 44 constructed entirely of prepreg fabric layers 82, 96, 104 resists shear loads. The first spar cap 56 constructed as a mixture of prepreg fabric layers 82, 96, 104 and prepreg tapes 92, 98 and the second spar cap 66 constructed as a mixture of prepreg fabric layers 82, 96, 104 and prepreg tapes 94, 102 resist bending loads.

[0046] Since various modifications could be made in the aircraft structure and method of construction thereof described and illustrated herein without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not limiting. Accordingly, the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.

Claims

1. An aircraft wing spar comprising: a web located at a central portion of the wing spar, the web having a length extending along the length of the wing spar, the web being constructed solely of prepreg fabric; a first spar cap located on a first edge of the web, the first spar cap having a length extending along the length of the web, the first spar cap being constructed from prepreg tape and the prepreg fabric of the web; and a second spar cap, the second spar cap being located on a second edge of the web, the second spar cap having a length extending along the length of the web, the second spar cap being constructed from prepreg tape and the prepreg fabric of the web, wherein the prepreg tape is a unidirectional prepreg tape oriented along the length of the first spar cap and the length of the second spar cap, and Wherein, the wing spar has a C-shaped channel cross-section configuration.

2. An aircraft wing spar according to claim 1, wherein: a first portion of the prepreg fabric of the web extending from the first edge of the web and over the first spar cap; and A second portion of the prepreg fabric of the web extends from the second edge of the web and over the second spar cap.

3. An aircraft wing spar according to claim 2, wherein: said first portion of said prepreg fabric of said web is interleaved with said prepreg tape of said first spar cap; and The second portion of the prepreg fabric of the web is interleaved with the prepreg tapes of the second spar cap.

4. An aircraft wing spar according to claim 3, wherein: said first portion of said prepreg fabric of said web is interleaved with said prepreg tapes of said first spar cap in alternating layers; and The second portion of the prepreg fabric of the web is interleaved with the prepreg tapes of the second spar cap in alternating layers.

5. The aircraft wing spar of claim 2, wherein: the first portion of the prepreg fabric of the web extends from the first edge of the web at an angle relative to the web; and The second portion of the prepreg fabric of the web extends from the second edge of the web at an angle relative to the web.

6. The aircraft wing spar of claim 2, wherein: the first portion of the prepreg fabric of the web being formed in a first bend as the first portion of the prepreg fabric of the web extends from the first edge of the web; the second portion of the prepreg fabric of the web being formed in a second bend as the second portion of the prepreg fabric of the web extends from the second edge of the web; The prepreg tape of the first spar cap is positioned at least 0.25 inches from the first bend; and The prepreg tape of the second spar cap is positioned at least 0.25 inches from the second bend.

7. An aircraft wing structure comprising: a spar having a length dimension between a fuselage end of the spar and an opposite tip end of the spar; the spar having a web at a central portion of the spar, the web having an elongated rectangular configuration, the web having a height dimension between a top edge of the web and an opposite bottom edge of the web, the web having a length dimension between the fuselage end of the spar and the opposite tip end of the spar, and the web having a thickness dimension between a first side surface of the web and an opposite second side surface of the web; a first spar cap, the first spar cap being located on a top edge of the web, the first spar cap having an elongated rectangular configuration, the first spar cap having a length dimension extending along the top edge of the web between the fuselage end of the spar and the tip of the spar, the first spar cap having a width dimension protruding from the top edge of the web, and the first spar cap having a thickness dimension between a top surface of the first spar cap and an opposing bottom surface of the first spar cap; a second spar cap, the second spar cap being located on a bottom edge of the web, the second spar cap having an elongated rectangular configuration, the second spar cap having a length dimension extending along the bottom edge of the web between the fuselage end of the spar and the tip of the spar, the second spar cap having a width dimension projecting from the bottom edge of the web, and the second spar cap having a thickness dimension between a top surface of the second spar cap and an opposing bottom surface of the second spar cap; The web is composed only of pre-impregnated fabric; said first spar cap being constructed from a first prepreg tape and said prepreg fabric of said web; and said second spar cap being constituted by a second prepreg tape and said prepreg fabric of said web, wherein the first prepreg tape of the first spar cap is a unidirectional prepreg tape in which fibers are oriented along the length direction of the first spar cap, and the second prepreg tape of the second spar cap is a unidirectional prepreg tape in which fibers are oriented along the length direction of the second spar cap, and Wherein, the wing spar has a cross-sectional configuration of a C-shaped channel.

8. An aircraft wing structure according to claim 7, wherein: a first portion of the prepreg fabric of the web extending from the top edge of the web and over the first spar cap; and A second portion of the prepreg fabric of the web extends from the bottom edge of the web and through the second spar cap.

9. An aircraft wing structure according to claim 8, wherein: said first portion of said prepreg fabric of said web is interlaced with said first prepreg tape of said first spar cap; and The second portion of the prepreg fabric of the web is interlaced with the second prepreg tape of the second spar cap.

10. An aircraft wing structure according to claim 9, wherein: the first portion of the prepreg fabric of the web is interleaved with the first prepreg tape of the first spar cap in alternating layers; and The second portion of the prepreg fabric of the web is interleaved with the second prepreg tapes of the second spar cap in alternating layers.

11. The aircraft wing structure according to claim 8, wherein: said first portion of said prepreg fabric of said web extends from said top edge of said web at an angle relative to said web; and The second portion of the prepreg fabric of the web extends from the bottom edge of the web at an angle relative to the web.

12. The aircraft wing structure of claim 8, wherein: the first portion of the prepreg fabric of the web being formed in a first bend as the first portion of the prepreg fabric of the web extends from the top edge of the web; the second portion of the prepreg fabric of the web being formed in a second bend as the second portion of the prepreg fabric of the web extends from the bottom edge of the web; The first prepreg tape of the first spar cap is spaced at least 0.25 inches from the first bend; and The second prepreg tape of the second spar cap is spaced at least 0.25 inches from the second bend.

13. A method of constructing an aircraft wing, comprising: forming a wing spar having a central web composed solely of prepreg fabric; forming a first spar cap on the wing spar, the first spar cap being composed of a first unidirectional prepreg tape and a first portion of the prepreg fabric of the central web; as well as forming a second spar cap on the wing spar, the second spar cap being composed of a second unidirectional prepreg tape and a second portion of the prepreg fabric of the central web, wherein the first unidirectional prepreg tape is a unidirectional prepreg tape oriented along the length of the first spar cap, and the second unidirectional prepreg tape is a unidirectional prepreg tape oriented along the length of the second spar cap, and Wherein, the wing spar has a C-shaped channel cross-section configuration.

14. The method according to claim 13, wherein: interlacing the first portion of the prepreg fabric of the central web with the first unidirectional prepreg tape; and The second portion of the prepreg fabric of the central web is interlaced with the second unidirectional prepreg tape.

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