How is the fuel supplied to the engine once the initial start spray is done?

The fuel supply to the engine after the initial start spray is achieved by the fuel manifold and nozzles for primary and secondary flow. In jet engines, the fuel system is designed to deliver fuel efficiently and reliably under a variety of operating conditions.

Once the initial start spray is initiated, fuel is supplied through a complex network involving the fuel manifold, which distributes the fuel to the engine. This manifold ensures that the fuel reaches the appropriate nozzles, where it is atomized and mixed with air for combustion. The primary flow refers to the main fuel flow needed for engine operation, while the secondary flow may be used for additional needs such as starting or varying engine power settings.

This method of fuel delivery is critical for maintaining the proper fuel-air mixture for effective combustion, thereby optimizing engine performance and efficiency. Other options, such as manual control or gravity feed, do not provide the systematic and controlled fuel delivery necessary for engine operation.