Hybrid electrical/mechanical turbine engine fuel supply system

A gas turbine engine system, comprising:

• a gas turbine engine including one or more fuel manifolds and a gearbox;
• a plurality of secondary fuel loads;
• an electric fuel metering pump having a fuel inlet and a fuel outlet, the electric fuel metering pump adapted to be selectively energized and, upon being energized, to draw fuel into its fuel inlet and supply the fuel, via its fuel outlet, to the one or more fuel manifolds;
• and
• a mechanically-driven fuel pump coupled to the gas turbine engine gearbox to be driven thereby, the mechanically-driven fuel pump having a fuel inlet and a fuel outlet, the mechanically-driven fuel pump fuel inlet in fluid communication with the electric fuel metering pump fuel inlet, the mechanically-driven fuel pump fuel outlet in fluid communication with the electric fuel metering pump fuel inlet and the plurality of secondary fuel loads,
• wherein the electric fuel metering pump may draw fuel into its fuel inlet from upstream of the mechanically-driven fuel pump fuel inlet.

A turbine engine fuel supply system, comprising:

• a priority flow line configured to supply fuel to one or more gas turbine engine fuel manifolds;
• a plurality of secondary fuel loads;
• an electric fuel metering pump having a fuel inlet and a fuel outlet, the electric fuel metering pump adapted to be selectively energized and, upon being energized, to draw fuel into its fuel inlet and discharge the fuel from its fuel outlet for supply to the priority flow line;
• a mechanically-driven fuel pump having a fuel inlet and a fuel outlet, the mechanically-driven fuel pump fuel inlet in fluid communication with the electric fuel metering pump fuel inlet, the mechanically-driven fuel pump fuel outlet in fluid communication with the electric fuel metering pump fuel inlet and the plurality of secondary fuel loads;
• and
• an ecology valve mounted on the priority flow line downstream of the electric fuel metering pump.
• wherein the electric fuel metering pump may draw fuel into its fuel inlet from upstream of the mechanically-driven fuel pump fuel inlet.