GB670366A - Device for protecting against icing, and for de-icing outer elements of aircraft - Google Patents

Abstract

670,366. De-icing aircraft. SOC. NATIONALE D'ETUDE ET DE CONSTRUCTION DE MOTEURS D'AVIATION. Aug. 3, 1949 [Aug. 4, 1948], No. 20229/49. Class 4. [Also in Group XIII] In a de-icing apparatus for aircraft elements air from the vicinity of the leading edge of the element is fed to a combustion chamber independent of the aircraft propulsion plant, the products of combustion being conveyed to the outer surface of the element, over which they are discharged as a thin layer which mingles with the boundary layer and thus improves the aerodynamic qualities of the element. As applied to an aerofoil such as a wing 1, Figs. 1 and 2, air entering an opening 3 in the undersurface near the leading edge passes into a combustion chamber 5, in which fuel supplied to a burner 6 is ignited by a sparking plug 8, the products of combustion passing through pipes 10 to slots 11 in the upper surface. through which they are discharged in a rearward tangential direction. Fig. 4 shows a half-section of an engine air intake, in which combustion air enters through an axial duct 12 and cooling air through a co-axial annular duct 13. A portionof the cooling air passes through passages 4 to the independent combustion chamber 5, the combustion products being led to an annular duct 11 near the leading edge of the inner surface 17 of the cooling air duct. from which duct they pass through slots 22 rearwardly over the surfaco 17. In the ease of the air inlet shown in Fig. 7, the products of combustion are fed to two duets 11a, 11b from which they are discharged rearwardly over the inner and outer surfaces 17, 18 of the cooling air duct and also, through ducts 30. to the leading edge of the intake. A duct 28a within the duct 30 is traversed by cold air entering a chamber 28 surrounding the duct 11a. In the further embodiment shown in Fig. 13, an inner cowl 1a carries an axial burner 5 to which air is supplied through openings 34, and the combustion products pass through pipes 10 and openings 35 over the cooling air duct surface 17. The pipes 10 lie in depressions 3S at the leading edge of the air intake 12, cold air passing through passages 37 formed by the depressions 38 and then being discharged over the surface 17 through openings 39. In addition, hot lubricating oil may be circulated by pipes 42, 43 through a, chamber 40 at the leading edge 15 of the outer cowling.