LIGHT TWIN-ENGINED MULTI-PURPOSE AIRCRAFT LADOGA-9 FOR GROUND AND WATER BASES Russian patent published in 1999 - IPC

FIELD: aviation; manufacture of light twin-engined multi-purpose aircraft. SUBSTANCE: aircraft has fuselage with rigid bottom made in form of hull, cantilever wing, tail unit and twin-engined power plant. Wing is raised above upper surface of fuselage by 0.25 m. Two turboprop engines have power about 800 hp each. Engines are enclosed in nacelles and are located on center-section wing. They are provided with multi-blade reversible tractor-type propellers and turbo-supercharged system. Rigid bottom is made with transversal flare of 20 to 25 deg and one planing step. Lower portion of fuselage after planing step is raised by angle of 8 deg relative to level and performs function of second planing step. Fuselage has hydrodynamic ratio of about 6.2 and aerodynamic cleanness factor of 0.021 for steady planing on water surface at prelaunch speeds with trim angles of 8.5 to 9 deg. Aircraft performs safe flight at trim angles from 3 to 8 deg at optimal combination of aerodynamic efficiency and seaworthiness. Volume of passenger cabin is equal to 23 cu. m at height of 1.7 m and width of 1.6 m. Sealing shaping strips of both doors of aircraft ensure pressurization of aircraft at an altitude of 3000 m. Torsion-box type wing is used for main fuel tanks having capacity of 650 kg of fuel each. Each additional fuel tank has capacity of 100 kg of fuel. EFFECT: improved service characteristics. 10 cl, 15 dwg