GB499068A - Improvements in and relating to wings, control surfaces, rudders and the like of aircraft - Google Patents

Abstract

499,068. Aircraft structures. JUNKERS FLUGZEUG - UND - MOTORENWERKE AKT.-GES. Feb. 3, 1938, No. 3395. Convention date, Feb. 8, 1937. [Class 4] Wings and other aircraft components are provided with box girders which occupy a considerable fraction of the chord and which are constituted by longitudinal walls adapted to resist buckling and bending, thin by comparison with their length and formed without any sudden change of thickness in the longitudinal direction, at least two adjacent walls being rigidly connected, the remaining connections being constructed so that they permit relative movement between the walls they connect. Various forms of girder are shown diagrammatically: in one form, Fig. 1, walls 1 and 3 are rigidly connected and walls 2 and 4 are articulated to each other and to the walls 1, 3 ; alternatively the connection between walls 2 and 4 also is rigid. In another form the walls are divided in a plane containing the neutral axis of the spars the connections between the part side walls so formed and the upper and lower walls being rigid. In a further form, Fig. 5, walls 1, 2, 3 are rigidly connected and wall 4 is attached to the side walls by joints comprising bolts 19 interconnecting thin contacting flanges 17, 18. Walls 1 and 4 which form parts of the upper and lower boundaries of the wing each comprise a corrugated plate 14 firmly secured on both sides to tension and compression resisting members 15, 16. Transverse bracing members may be employed at points of localized stress such as engine mounting attachment points.