Abstract: The known control systems for reducing NOx in the combustion systems of past gas turbine engines has incorporated a variety of expensive and complicated techniques to reduce the NOx level. The present apparatus reduces the formation of NOx within the combustion zone by controlling the air portion of the air/fuel ratio. The present apparatus includes a device for controllably varying the quantity of compressed air directed into a manifold resulting in controlling the air to a plurality of injection nozzles and into a combustor. A throttling mechanism moves between an open position and a closed position varying the flow rate of compressor air to the combustor apparatus provides an economical, reliable and effective method for reducing and controlling the amount of nitrogen oxide (NOx) carbon monoxide (CO) and unburned hydrocarbon (UHC) emitted from the gas turbine engine.

Abstract: A controller [20] for scheduling the flow of a liquid fuel to a gas turbine engine [16]. The controller includes a fuel valve assembly [246], a compressor discharge pressure responsive (P.sub.CD) actuator [150], a differential linkage assembly [152] which is connected to the P.sub.CD actuator and a fuel demand responsive actuator [142] and operates a metering valve [154] in the fuel valve assembly.

Abstract: A split type fuel manifold for gas turbine engines which includes a simple check valve rather than the heretofore used individual valves or complex central valve for uniformly distributing fuel to an array of liquid fuel injectors supplied by the manifold.