GB319983A - Improvements in aircraft with particular reference to airfoils - Google Patents

Abstract

319,983. Burnelli, V. J., and Wilford, E. B. Nov. 14, 1928. Planes and the like, construction of; steering, balancing, and regulating altitude.-An aerofoil is made with a central section 11, Figs. 1 and 2, supporting telescopic end sections 22, 31 which are capable of movement on arcuate tracks 15. Sparrs 23, 32 on the respective sections are attached to arms 28, 28<1> formed with racks 29, 29<1> engaged by sprocket wheels 18 driven from a central sprocket wheel. The arrangement of tracks is such that the trailing edge is arranged to be low ered more than the leading edge. Transverse ribs 12, 13 and compression ribs 14, Fig. 4, are provided, the latter preferably forming the housings for the tracks and some of the operating means therefor. A deflector 24 extends beyond the upper face of the leading section 23 and an extension 25 of the lower face prevents air entering between the entering and central section. The trailing edge section 31 may be moved by means indicated in Fig. 5 and comprising a sliding shaft 38, crank-arm 36, link 35 and horn 34. A universal joint is provided at 37 and a slotted coupling 40 is connected by an arm 42 with an operating rod 43. Auxiliary ailerons are provided preferably supported by a pair of struts in positions either vertically above or below the main aerofoil, the lateral stability being increased thereby during a high angle of attack. Preferably each aileron is pivoted to the struts at a point slightly in advance of the centre of pressure thereon.