GB387719A - Improvements in or relating to aircraft structures - Google Patents

Abstract

387,719. Storing fuel on aircraft. DUNCANSON, F., Merecoombe, Gothering- ton, Gloucestershire. Aug. 13, 1931, No. 22879. Addition to 326,870, [Class 4, Aeronautics]. [Class 4.] The tapered tubular spar of the parent Specification is adapted to act as a liquid storage chamber being rendered fuel-tight over the whole or a portion of its span and provided with filling and draw-off apertures. Fig. 3 shows the spar 17 provided with transverse bulkheads 18 which with the central portion of the spar form a fuel tank 180. Perforated baffle plates 19 restrict the movement of the liquid. When the full length of the spar is employed it is subdivided by numerous baffle plates which may be of the type shown in Fig. 14 or Fig. 16, that of Fig. 14 comprising an annular U-shaped frame 119 such as described in the parent Specification to which is detachably secured a wire gauze or chamois leather baffle 190. When the spar is formed of a central parallel portion athwart the body and joined to tapering portions in the wings the central portion only may be used as a tank. Alternatively the tank portions may be arranged on one or both sides of the body and exterior thereto. Applications to twin-engined machines are shown in which the parts of the spar adjacent the engine are used as fuel containers. In cases where the engines are mounted on the level of the wings as shown in Fig. 9, the top half of the spar only is used as a fuel container, a bulkhead 21, Fig. 10, being provided approximately midway of the spar depth, which bulkhead may be provided with tapering channel portions 210 for stiffening and for improving drainage. The portions of the spar below the horizontal bulkhead may also be employed for fuel storage. Oil tanks 30, Figs. 10 and 12, may be fitted adjacent the tanks 180 and may be provided with surface oil coolers 31 on the top or bottom surface of the spar being arranged to project forwardly of the wing into the air stream. The metal plates forming the spar tube at the tank portion will be close riveted at their seams and a jointing material or fluid will be applied to the contacting surfaces or the seams may be rendered fluidtight by soldering, brazing or welding. Vertical longitudinal partitions may be fitted. Apertures or manholes 40, Fig. 3, with detachable covers may be provided on the spar. The outermost bulkheads 18 and any division plates intermediate the inner bulkhead and the outer ends may be made weaker than the spar itself so that distortion of the spar due to accident will cause them to rupture and permit the contained fuel to flow toward the wing tips.