What is the primary function of the FODS controller?

The primary function of the FODS (Fault Operational Data System) controller is to conduct built-in tests of fire and overheat detectors. This function is crucial as it ensures that the safety systems associated with the APU (Auxiliary Power Unit) are operational and can effectively detect hazardous conditions that may arise, such as fires or overheating. Regular testing of these systems helps maintain safety standards and operational readiness, allowing for timely intervention if any issues are detected.

Monitoring APU operating temperatures, controlling fuel flow, or performing diagnostics while important roles, do not directly pertain to the specific responsibility of the FODS controller concerning safety and detection tests. The emphasis on fire and overheat detector testing highlights the FODS controller's focus on safety and the integrity of auxiliary power operations.