GB517775A - Aircraft construction - Google Patents

Abstract

517,775. Flying boats. MARTIN CO., G. L. July 28, 1938, No. 22495. Convention date, July 28, 1937. [Classes 4 and 113 (ii)] A flying boat has a high wing braced by struts pivoted to adjustable brackets on the hull, sponsons being pivoted to the same brackets. Provision for angular adjustment of the sponsons relatively to the hull is provided. As applied to a high wing flying boat, Fig. 1, the main plane is braced by inclined struts 16, 17 which are pivotally connected at their lower ends to adjustable brackets such as Fig. 11, to which the sponsons 25 are also pivotally attached, the forward struts 16 passing through wells 31 in the sponsons. Movement of the latter is controlled by twopart struts 18, 19 of which each part is pivotally connected to the wing strut, the upper part being pivotally connected to the main plane, and the lower parts, which incorporate shock absorbing devices and which are also adjustable in length, being connected to the sponsons, Fig. 3. The upper surface of the sponson corresponds to that of N.A.C.A 2300 series aerofoil whilst the lower surface is formed with a tapered step 32 so disposed as to co-operate with the forward hull step 11. The.means for adjusting the root end of the sponson relative to the hull may be manual or power means. As shown in Fig. 11, bracket 28, is vertically movable by rotation of a screw 71. The mounting of the after end of the sponson is similar but the bracket is wholly above the top surface of the sponsons. The dihedral angle of the spbnsons may be adjusted by means such as shown in Fig. 15 in which the effective length of the strut is variable by moving a piston 53 in a cylinder 52 by hydraulic means comprising an electric or hand pump 59 drawing fluid from a reservoir 58, a control valve 57 and pipe lines 55, 56. The sponsons may be used for load carrying and, as shown in Fig. 12, may be adapted to serve as fuel tanks. In this form the tank area is defined by main beams, root rib and outer rib. The tank is subdivided into a number of compartments by partitions 37 communication between which is effected by longitudinal corrugations 39 formed in the lower skin Fig. 3. The tip section is separately constructed and may be upwardly tilted and the bottom surface upwardly curved as shown at 44, Fig. 9. Alternatively the tip section may continue the taper of the main section. The under surface of the hull is also corrugated in order to cushion the water shock on alighting.