US Patent 7762080 Fuel metering pump calibration method

A system and method for accurately supplying fuel flow to a gas turbine engine from a fuel metering pump regardless of variations in operating conditions of the fuel metering pump. The system determines an updated flow characteristic curve for an electrically powered positive displacement pump that is configured to supply fluid via a valve that is configured to open at a predetermined fluid inlet pressure. Electrical current is supplied to the pump to thereby cause the pump to supply the fluid to the valve. The electrical current supplied to the pump is monitored to determine when the valve opens, and one or more points on the updated flow characteristic curve are determined based on the determination of when the valve opens.