What does a "circuit breaker" do in an aircraft?

A circuit breaker in an aircraft functions to protect electrical circuits from overloads. In the event of a fault that causes a circuit to draw more current than it is designed to handle, the circuit breaker interrupts the flow of electricity. This prevents potential damage to the electrical components and wiring, maintaining the safety and integrity of the aircraft's electrical systems.

Understanding the role of circuit breakers is critical in aviation, as they ensure that electrical components can operate safely under normal conditions. Should any malfunction occur, pilots and maintenance crews can monitor the status of the circuit breakers to diagnose issues closely related to the electrical systems without risking extensive damage or failure of vital components.

Other functions mentioned in the options are not related to the role of a circuit breaker. For example, regulating engine speed, controlling fuel flow, and tracking altitude involve different systems and mechanisms that serve specific functions distinct from the protective role of circuit breakers.