GB439954A - Improvements in aeroplane wings - Google Patents

Abstract

439,954. Aircraft wing structure. A.T.S. CO., Ltd., 3, Clement's Inn, London, and LLOYD, J., Whitley Aerodrome, Coventry. June 13, 1934, No. 17516. [Class 4] An aeroplane wing (or part thereof) covered with fabric or other fairing of which the rigidity is small relative to that of the internal structure, comprises a main strength member comprising two side webs connected together by top and bottom plates so as to form a box girder which approximately fits the wing profile at and in the vicinity of its greatest depth over a width of from one-fifth to two-fifths of the average wing chord, the plates being longitudinally corrugated with not less than five corrugations and being supported by transverse bulkheads or supports. Fig. 2 shows in plan view a wing spar which tapers in depth but not in width from wing centre to wing tip and which comprises top and bottom corrugated plates 1, 2, Fig. 3, connected by transversely corrugated webs 3, 4. The corrugations of plates 1 and 2 are uniform throughout the span but the plates may be built up from a number of plates of successively decreasing thickness united as at 7, 8, 9, Fig. 2, by lap or other joints. The plate elements may each be constructed from two sheets centrally joined as at 10, Fig. 3. Narrow tapering reinforcing strips 11, 12, Figs. 3 and 5, may be employed as shown in Fig. 2. Webs 3, 4 have vertical corrugations 13, Fig. 4, which at top and bottom edges are received by and secured to channels 14 to which plates 1, 2, and 11, 12 are riveted. Flanged elements 15, Figs. 4 and 5 are riveted to the channels 14 and to the webs in alternate corrugations. Transverse supports comprise channel members, 16, 17, Fig. 3, braced apart by a strut 18 and trussed by diagonal members connected to the centres of the webs. Means of attachment for nose and tail ribs comprise fittings 25, 26, 27, 28 secured to webs 3, 4 and plates 1 and 2 in line with the transverse supports. According to modifications the transverse supports may comprise bulkheads formed from plane or corrugated plates with flanged edges and according to the Provisional Specification the compartments thus formed in the girder may be used for fuel storage or like purposes. The side members 3, 4 may be formed of flat sheet metal reinforced by transverse or longitudinal stiffeners or may be of lattice construction. Covering of fabric, wood, celluloid or thin metal may be attached directly to members 1, 2 or to rail members affixed thereto. Alternative forms of corrugated sheet are shown in Figs. 6 and 7. The Specification contains an analysis of the factors influencing the shape and spacing of the corrugations in relation to the thickness of material to be employed. Specification 384,838 is referred to.