Feb' 5» 1946­ ' ­A. A. GAssNER 2,394,12 AIRPLANE WING STRUCTURE _AND METHOD OF „MAKING THE SAME Filed April 29, 1941 ' 2 sheèts-sheet 1 Feb. 5, '1946.7 A, A. GAssNER v 2,394,162 AIRPLANE WING STRUCTURE AND METHOD OF MAKING THE SAME Filed April 29. 1941 I 2y Sheets-Sheet 2 _ l „ . INVENTOR | " ' . ‘"‘ì ALFRED A.GAs_sNER Patented Feb. 5, 1946 ~ 2,394,162 UNITED STATE s~l Parrain*A orslcs AIRPLANE WING STRUCTURE AND METHOD ’ 0F MAKING THE SAME Alfred A. Gassner, New York, N. Y., assignor, by mesne assignments, to William B. Scarborough, Englewood, N. J., as trustee ­ » „ Application April 29,1941, Serial No. 390,895 Y 10 Claims. (Chau-123) This invention relates to airplane wing struc shaped, the plies are bonded together kby means ~ tures and methods of making the same, and has of a. suitable adhesive, preferably thermosetting particular reference to the manufacture of mul adhesive interposed between or applied to the tiple-ply airplane wings and similarly-construct plies before they are assembled in the manner ed airplane parts, such as ailerons, flaps. eleva described, heat and pressure being utilized in tors, rudders, and the like. bonding so that the plies form a self-sustaining The construction of airplane wings and the like unit of the configuration described. of multiple plies of sheet material, such as wood This front shell is then fitted with chordwise bonded together with thermo-setting adhesive, en' capstrips which are arranged in> pairs opposite ables-the apportionment of load-sustaining ma 10 each other on the upper and lower inner sur terial throughout the wing in accordance with faces at spaced intervals lengthwise of the shell the stresses to which the wing is subjected in and are bonded thereto. After these opposite flight without the use of rivets and other separate cap strips have been so applied to the shell, they fastening members. A wing so constructed is are grooved longitudinally, i. e.. chordwise of the light and strong, and may be rapidly formed to shell, and thin pre-shaped chordwise webs of ply the end that aircraft production is expedited. «wood or other material are fitted in the grooves The construction of wings and the like of ply of each pair of opposite cap strips and secured wood or equivalent material nevertheless presents in place by suitable adhesive, or the like. numerous construction problems,for owing to the . After assembly of the nose shell in the manner nature of the material used, it must be assembled 20 described,­ a rear shell of similar J-shaped cross in layers or plies, which must be bonded into a section is formed in the same way and is inserted rigid and substantially homogeneous structure part way into the nose shell, but in inverted po- _ under conditions such that there are no voids be sition with respect thereto, so that the long-arm tween the plies, which are difllcult to ascertain of the rear section becomes a complement of the after bonding', and there must be no unusual 25 lower surface of the wing and the short arm stresses set up within the material during man thereof lies against the under side of the long ufacture which might lead to subsequent failure. arm of the nose shell. In this position the two This is particularly so where large Wings having shells are bonded together under heat and pres substantial surface areas are required because the sure by means of thermosetting adhesive, so that expanse of the material which must lbe used ren 30 the two oppositely arranged shells form the upper ders proper assembling and effective bonding ex and lower surfaces of the wing section. Trans tremity difficult and often uncertain. verse or chordwise cap strips are bonded to the In accordance with this invention, a multiple upper and lower inner surfaces of the rear shell, ply aircraft wing structure and method of mak routed or grooved, and fitted with transverse ing the same are provided which enables the con 35 plates or webs in the manner previously described. struction of large wings and other parts of su Depending upon the desired width of the wins. perior strength with the same facility as small additional rear shells of the same or similar J» wings and other parts may be constructed, with shaped section may be successively bonded to the out sacrifice of light weight and without compli aforementioned rear or second shell inthe same cation of the construction process. The method 40 way that the latter was bonded lto the front or of this invention also enables proper apportion nose shell. Whether one or more rear shells are ment of the plies in accordance with the load employed. a false or rear spar of U-shaped cross requirements of the wing so that the strain is section is inserted to complete the wing section, distributed over the whole surface of the wing this false spar being placed Just within the trail and thus a true stressed skin wing is provided. 46 ing edge of the Wing and serving as a support for The invention comprises assembling wood plies, ailerons, flaps, or the like. '_ preferably with 'the grains of successive plies run It will be seen that the airplane wing structure ning at an angle to each other, and conforming of this invention and the method of producing them to predetermined contour by means of a die the same provide avery simple and effective mul of proper configuration, so that, in case of a nose 50 tiple-ply wing of any desired size, this wing hav piece for a wing, for example, it has a generally ‘ing 4great strength without sacrifice of lightness J-shaped cross-section with the curve of the J and without requiring the use of separate spanwlse of this section constituting the nose or leading spars or -girders. since the vertical webs of the edge of the wing, and the long arm thereof the second or rear shell or shells act as shear webs top surface of the wing. So assembled and or spars, and no interior bracing ls needed, as 2 8,804,108 ' ulcwlngstrucmrescfmanmncmœnacn., thick attire mid-section of the upper surface. and compression,and mixed tension andeompres will observedthat plies I2', I2, i8' and'il . sion. auch as torsion. provided with a deep indentation at For a more complete understanding oi' the in tip ends, which extends along the vention, reference may be had to the accomnelly- ’ ottbewingsothatthethickness ing drawings, in which: oftbewallattbeleadlngedgeofthewingde Figure V1 is a development of the nose or front progressively from root to tip, vis., seven .shell of an airplane wing'constructed according tothreepliesintheillustratedcœe.l to this invention and showing the arrangement oi Inthis mannenthethicknessofthewalloi‘ the superposed plies; ' ­ Fig.2isatransversesectionofthenœeorfront shell after the plies have been bonded together; » Pig. 3 illustrates the-shell equipped with oppo sitetransversecapstripsonitsupperandiower inner surfaces; ` - 15 -Flg.4isanenlargedtransversesectionas seenalongtheline4-4ofFig.3,showlngthe ingoneor moresparstakingallormostofthe construction of one of the cap strips after it has Y load. _ „ been grooved or routed to provide for the chord me plies with their edges scarfed to overlap wise webs or stringers; ` smoothly, are assembled, with the thermosetting Fig. 5 is a transverse section through the sec- ­ adhesive interposed between them. in a female ond or rear shell; . Y, die having the proper airfoii configuration. and Fig.6illustratesthle'r'nanner'ozifassemblingthe­ arepressedagainsttheinteriorofthedieby nose and rear shells and the apparatus for eiiect means of fluid pressure',v such as ­air under pres ing the bonding operation; and sure applied against the surface of a rubber Fig. 7 illustrates the completed wing section as blanket sealed along the edges of the die beyond seen at the root end. Y the edges of the plywood assembly. Further Referring to Fig. 1 of the drawings, numeral Il . details of the construction of the die and the designates the nose shell whichis shown in Fig. 1 method of forming curved shells are disclosed in as in developed form. The shell consists of a se 30 the patent to J. H. Potchen and 0. H. Basquin. ries of layers or plies of wood in superposed rela No. 2,308,453, granted January 12, 1943. tion, each, except the small ones, comprising a Heat is simultaneously applied to the plywood series of edge-glued strips and cut out to pre assembly, so that the adhesive is fused and im scribed shape in accordance with the contour ot pregnates the nbres of the wood and bonds the templets. These layers or plies are laid one upon adjacent layers together -to form the J-shaped the other in the proper relationships shown in nose or iront shell shown in Fig. v2, which has r Fig. l, with sheets of dry thermo-setting adhesive the spanwlse length shown in Fig. 1. The trans such as a phenol, urea, orl similarl synthetic resin, verse or chordwise width of the long leg of the interposed between them. In the alternative self-sustaining shell Il is preferably the entire arrangement, a water-dispersion of a thermo 40 width of the top of the completed wing. and . setting resin may beappliedv to the abutting sur serves as the continuous chordwise base of the faces of the plies or layers and the whole dried to wing, as will be shown. ' ' the proper water content. Molded cap strips Il and 2l, constituting AsshowninFlg.1,thesurfaceplyHisalarge superimposed layers of decreasing width of ply sheet, preferably consisting of. three plies with wood bonded together. are applied opposite each ‘ the grain of the outer plies running spanwise of other on the upper and lower inner surfaces ci ­ the wing and the grain of the intermediate ply.