Abstract: A fuel flow control valve is adapted to control the flow of fuel in a spill line to control the amount of fuel usable in a two speed gas turbine. The valve includes fluid pressure operated valve means controlled by two variable volume fluid pressure chambers to provide appropriate fuel flow for `run` and `idle` conditions, and positioning means to automatically position the fluid pressure operated valve means when the control valve is at rest to provide a flow of fuel appropriate for `start-up` of the gas turbine that is greater than the flow required in the `idle` condition but less than that required in the `run` condition. Operating fluid pressures connected to the chambers may comprise either gaseous fluid pressures tapped from a stage of the compressor of the gas turbine or a combination of said gaseous pressure source and a liquid fluid pressure source preferably comprising a fuel pressure supply tapped from the fuel supply line to the gas turbine.