Patent ID: 9556838
Date: 2017-01-31
CPC Classifications: B64C,B64D,F02C,F02M,Y10T

Claim:
1. A fuel supply system for an aircraft for delivering in use fuel from a fuel tank to an aircraft powerplant, the fuel supply system comprising: a fuel flow passage connecting the fuel tank and the aircraft powerplant and being configured to allow in use fuel to flow from the fuel tank to the powerplant, the fuel flow passage having a downstream end adjacent the powerplant and an upstream end adjacent the fuel tank, a downstream pump associated with the aircraft powerplant and configured to draw fluid along the fuel flow path so as to supply the fluid to the powerplant in use, an upstream pump disposed in or associated with the fuel tank and operable to pump fluid along the fuel flow passage, a pump inlet pressure sensor configured to monitor a pressure at an inlet to the downstream pump, a pump outlet pressure sensor disposed at an outlet of the downstream pump and configured to monitor a pressure at an outlet of the downstream pump, and a fuel system controller configured to, in response to the pressure at the inlet to the downstream pump monitored by the pump inlet pressure sensor, control the upstream pump so as to maintain the pressure at the inlet to the downstream pump at or above a threshold pressure, and additionally configured to, in response to the pressure at the outlet of the downstream pump monitored by the pump outlet pressure sensor, adjust the threshold pressure.