Which components make up the ignition system?

Which components make up the ignition system?

• A. Battery, alternator, ignition switch, wiring harnesses.
• B. Alternator, FADEC, Engine fuel control, Ignition exciter, Main igniter, AB igniter, AB flame sensor, Two fan speed transmitters, Thermocouple harnesses.
• C. Starter motor, fuel pump, ignition coil, spark plugs.
• D. ECU, sensor, actuator array.

Answer: (B)

Ignition systems on jet engines are not just a spark source; they include the devices that generate the ignition pulse, the actual igniters, and the sensors and controls that ensure reliable light-off and monitor flame. The components in this set form a complete ignition subsystem: the ignition exciter provides the high-energy timing signals to the igniters, while the main igniter and AB igniter are the devices that create the spark to ignite the fuel-air mixture. The AB flame sensor checks for flame presence so the control system can confirm successful ignition and shut down ignition if flame is not detected. Supporting data and control elements such as the two fan speed transmitters supply rotational speed information used by the engine control to time ignition, and thermocouple harnesses feed temperature readings that help assess combustion conditions. The FADEC and engine fuel control coordinate when ignition should occur, particularly during start, and manage fuel delivery while the alternator provides the electrical power that drives this whole system. This combination of ignition drive, flame sensing, and the associated sensing and control links is what makes up the ignition system. Other options miss essential ignition components or bundle in systems that aren’t specific to ignition alone, such as a starter motor or general ECU/sensor/actuator arrays.

Ignition systems on jet engines are not just a spark source; they include the devices that generate the ignition pulse, the actual igniters, and the sensors and controls that ensure reliable light-off and monitor flame. The components in this set form a complete ignition subsystem: the ignition exciter provides the high-energy timing signals to the igniters, while the main igniter and AB igniter are the devices that create the spark to ignite the fuel-air mixture. The AB flame sensor checks for flame presence so the control system can confirm successful ignition and shut down ignition if flame is not detected. Supporting data and control elements such as the two fan speed transmitters supply rotational speed information used by the engine control to time ignition, and thermocouple harnesses feed temperature readings that help assess combustion conditions. The FADEC and engine fuel control coordinate when ignition should occur, particularly during start, and manage fuel delivery while the alternator provides the electrical power that drives this whole system. This combination of ignition drive, flame sensing, and the associated sensing and control links is what makes up the ignition system. Other options miss essential ignition components or bundle in systems that aren’t specific to ignition alone, such as a starter motor or general ECU/sensor/actuator arrays.