What is considered an electrical emergency?

What is considered an electrical emergency?

• A. Loss of all generators
• B. Loss of battery power
• C. APU surge
• D. Overvoltage on bus

Answer: (A)

Electrical emergencies are defined by a loss of power generation. When all generators fail, there is no source of electrical power feeding the aircraft buses, so essential systems must run on a limited battery supply, which is only temporary. That complete loss of generation is the most severe electrical condition the airplane can face. The other options describe abnormal conditions or partial faults rather than a total power loss. An APU surge indicates an abnormal electrical output from the APU rather than a confirmed loss of generation. An overvoltage on the bus is a fault condition that the system would protect against, not a loss of power itself. Loss of battery power, while serious, doesn’t necessarily equal zero generation if engines or the APU are still supplying power. So the scenario with no generator output at all best fits an electrical emergency.

Electrical emergencies are defined by a loss of power generation. When all generators fail, there is no source of electrical power feeding the aircraft buses, so essential systems must run on a limited battery supply, which is only temporary. That complete loss of generation is the most severe electrical condition the airplane can face.

The other options describe abnormal conditions or partial faults rather than a total power loss. An APU surge indicates an abnormal electrical output from the APU rather than a confirmed loss of generation. An overvoltage on the bus is a fault condition that the system would protect against, not a loss of power itself. Loss of battery power, while serious, doesn’t necessarily equal zero generation if engines or the APU are still supplying power. So the scenario with no generator output at all best fits an electrical emergency.