Fuel system for canard aircraft

Abstract

A high wing Canard aircraft mounts three strake fuel tanks within the top of the aircraft fuselage on the right and left sides thereof in a fore and aft array interconnected by horizontal interconnect lines at the bottoms of the strake tanks to provide an alternate fuel path in the event of tank-line contamination blockage and forming a secondary gravity feed system. A pair of wing tanks integrated to the high wing of the Canard aircraft, to the rear of the strake tanks, feed along with individual horizontal fuel lines from the strake tanks to a central fuel collector tank interposed between the main high wing sections with low pressure drop flapper check valves at the ends of the individual horizontal lines internally of the collector tank for preventing fuel from leaving the collector tank. The primary gravity feed system defined thereby isolates each tank from the other, thereby preventing large fuel excursions during extreme flight maneuvers. A sump tank integrated to and underlying the common collector tank supplies fuel through the main fuel supply line to the engine via primary and secondary boost pumps. The excess fuel returning from the engine at boost pump pressure functions as the motive fluid for jet pumps, one in the front of each forward strake tank and one in the outboard portion of each wing tank for supplying fuel to the collector tank at a rate one half of the engine take-off fuel demand. Overflow return lines are routed from the top of the collector tank back to each tank containing a jet pump. These lines also terminate with low pressure drop flapper check valves to prevent cross flow between tanks. Filler manifolds overlying one of the strake tanks to each side of the aircraft meter fuel to the tanks along one side, at a rate proportional to the tank size.