System and method for reduced flammability of an aircraft fuel system

摘要

Disclosed is a method for controlling the flammability of fuel vapors in an aircraft main fuel tank that is located in whole or in part in the fuselage contour. The method comprises a fuel system architecture and fuel consumption sequencing maintaining liquid fuel in said main tanks during all normal operations. Ceasing the withdrawal of fuel from the main tank when the fuel reaches a predetermined level thereby limiting the volume and flammability exposure time of the fuel vapor ullage. Once the predetermined level is met the fuel is supplied from wing tanks throughout the remainder of the mission. The predetermined main tank fuel level at which wing tank fuel begins to be consumed is determined by the aircraft flight reserves fuel volume stored in the main tank as well as the amount necessary to continuously submerge the main tank fuel pumps during the entire mission.

主权项

1. A method for controlling the formation of flammable vapors in an aircraft main fuel tank located in whole or in part in the fuselage contour wherein each wing includes a main fuel tank, a wing tank outboard of the main fuel tank and a collector tank disposed within the main fuel tank that is in fluid communication with the wing tank; the method comprising:
(a) initially consuming fuel in the main tank until the fuel quantity has reached a predetermined reserve level; (b) sensing that the fuel has reached the predetermined level; (c) initiating the operation of at least one valve to transfer fuel from the wing tank to the collector tank thereby maintaining the predetermined level of fuel in the main tank; (d) the collector tank including at least one flow limiter to deter the escape of fuel into the main tank; and (e) maintaining the reserve fuel in the main tank at the predetermined level throughout the remaining mission of the aircraft.