A fuel system for an aircraft engine, comprising: a fuel metering unit fluidly connectable to a fuel source of the aircraft engine; a flow divider separate from the fuel metering unit and mountable to the aircraft engine at a location remote from the fuel metering unit, the flow divider having a fuel inlet port fluidly connected to the fuel metering unit via a fuel line; and a primary and a secondary fuel manifold (14, 16) fluidly connected to the flow divider; wherein the fuel metering unit and the flow divider are configured to be operated in a fuel supply mode in which fuel is allowed to flow in a first direction through the fuel line from the fuel metering unit to the flow divider to feed the primary and secondary fuel manifolds (14, 16), characterised in that: the fuel metering unit and the flow divider are configured to be operated in an ecology mode in which fuel is allowed to flow in a second direction through the fuel line from the flow divider towards the fuel metering unit; the fuel system further comprises an ecology ejector; the fuel metering unit includes a discharge pressurizing valve having an inlet port fluidly connectable to a source of fuel, an ecology outlet port fluidly connected to a suction inlet port of the ecology ejector, and an inlet/outlet port selectively connectable in flow communication to either one of the inlet port or the ecology outlet port of the discharge pressurizing valve; the fuel inlet port of the flow divider is selectively fluidly connectable to the primary and the secondary fuel manifold (14, 16), the flow divider having an ecology outlet port selectively fluidly connectable to the primary and secondary fuel manifolds (14, 16), and a flow restrictor fluidly connected to the ecology outlet port; and the fuel line extends from the inlet/outlet port of the discharge pressurizing valve to the inlet port of the flow divider, the ecology outlet port of the flow divider fluidly connected to the fuel line via the flow restrictor. a fuel metering unit fluidly connectable to a fuel source of the aircraft engine; a flow divider separate from the fuel metering unit and mountable to the aircraft engine at a location remote from the fuel metering unit, the flow divider having a fuel inlet port fluidly connected to the fuel metering unit via a fuel line; and a primary and a secondary fuel manifold (14, 16) fluidly connected to the flow divider; wherein the fuel metering unit and the flow divider are configured to be operated in a fuel supply mode in which fuel is allowed to flow in a first direction through the fuel line from the fuel metering unit to the flow divider to feed the primary and secondary fuel manifolds (14, 16), characterised in that: the fuel metering unit and the flow divider are configured to be operated in an ecology mode in which fuel is allowed to flow in a second direction through the fuel line from the flow divider towards the fuel metering unit; the fuel system further comprises an ecology ejector; the fuel metering unit includes a discharge pressurizing valve having an inlet port fluidly connectable to a source of fuel, an ecology outlet port fluidly connected to a suction inlet port of the ecology ejector, and an inlet/outlet port selectively connectable in flow communication to either one of the inlet port or the ecology outlet port of the discharge pressurizing valve; the fuel inlet port of the flow divider is selectively fluidly connectable to the primary and the secondary fuel manifold (14, 16), the flow divider having an ecology outlet port selectively fluidly connectable to the primary and secondary fuel manifolds (14, 16), and a flow restrictor fluidly connected to the ecology outlet port; and the fuel line extends from the inlet/outlet port of the discharge pressurizing valve to the inlet port of the flow divider, the ecology outlet port of the flow divider fluidly connected to the fuel line via the flow restrictor. the fuel metering unit and the flow divider are configured to be operated in an ecology mode in which fuel is allowed to flow in a second direction through the fuel line from the flow divider towards the fuel metering unit; the fuel system further comprises an ecology ejector; the fuel metering unit includes a discharge pressurizing valve having an inlet port fluidly connectable to a source of fuel, an ecology outlet port fluidly connected to a suction inlet port of the ecology ejector, and an inlet/outlet port selectively connectable in flow communication to either one of the inlet port or the ecology outlet port of the discharge pressurizing valve; the fuel inlet port of the flow divider is selectively fluidly connectable to the primary and the secondary fuel manifold (14, 16), the flow divider having an ecology outlet port selectively fluidly connectable to the primary and secondary fuel manifolds (14, 16), and a flow restrictor fluidly connected to the ecology outlet port; and the fuel line extends from the inlet/outlet port of the discharge pressurizing valve to the inlet port of the flow divider, the ecology outlet port of the flow divider fluidly connected to the fuel line via the flow restrictor.