GB585408A - Improvements in or relating to jigs for use in the construction of wings and control surfaces for aircraft - Google Patents

Abstract

585,408. Making aircraft. FAIREY AVIATION CO., Ltd., CHAPLIN, H. E., and COSTIGAN, F. J. May 17, 1944, No. 9455. [Classes 83 (ii) and 83 (iii)] [Also in Group XXXIII] Work-holders.-In a method of constructing wings and control surfaces for aircraft, sections of the skin which have been bent to shape mechanically either by rolling or pressing, are placed in a mould which accurately defines the external profile of the wing or the like at each rib or similar part and are clamped tightly thereagainst throughout the process of fixing the skin to the internal structure. The mould is in two parts, each comprising a number of vertical members a at positions corresponding to the ribs of the wing section, an upper horizontal member b at the nose of the wing section, two lower horizontal members c at positions corresponding to the webs of the front and rear wing spars and a preformed steel sheet d shaped to the external profile of the wing section. The mould part for the upper surface of the wing is fixed to the ground whilst the part for the bottom surface is mounted on rollers e so that it may be wheeled into position against the first part to which it is secured by means of dowel pins g, clamps j, k at the top and clamps x, t on the feet, co-operating respectively with openings h, lugs n and lugs z. The feet of the fixed part have projecting rails v to receive rollers w carried by the movable part on eccentric spindles to enable the height of the mould part to be adjusted. Adapted to be wheeled into position between the outer mould sections before they are clamped together is a structure having wheels u, a table o conforming to the shape of the web of the rear spar and end members p supporting a nose jig bar 40 and the web of the front spar. The wing ribs comprise nose and interspar sections 21, 22 with the corresponding rib boom angle pieces 23, 24 which in the first instance are clamped to the members 21, 22 by means of detachable backing plates. These rib assemblies are temporarily secured to angles q on the table o and to the bar 40 so as to be assembled in position together with members 27, 28 which may be expanded by screw devices 29 so as to firmly hold the booms 23, 24 against the skin 44 which has been temporarily secured in the upper mould, the lower mould section being in the first instance clamped to the upper mould without the lower skin in position. Hand holes in the table and spaces between the uprights a of the lower mould section allow access to the interior of the wing for manipulating the expansion members and the drilling and riveting of the interspar booms and ribs, the upper front spars and booms 46 and the drilling and fixing of the upper skin 44 with self-tapping screws, is now performed, using the pressure plates, table and upper mould section as drilling- jigs. The pressure plates are removed and the lower mould section withdrawn whilst the lower skin is temporarily secured to it, after which it is again clamped to the upper mould section and the lower skin secured to the wing. On the upper side, the booms may be notched as at 25 to accommodate stringers 26.