What is the electrical power priority order?

What is the electrical power priority order?

• A. Ships generators, APU, GPU
• B. GPU, APU, Ships generators
• C. APU, GPU, Ships generators
• D. External power, ships generators, APU

Answer: (A)

Electrical power priority order is about using power sources in a defined sequence so the aircraft stays reliably powered while preserving options for emergencies. The highest priority is the ship’s generators because they are the primary, engine-driven sources tied directly to the aircraft’s electrical system and are available during normal operations. They provide stable, conditioned power to the essential and nonessential buses as needed, without needing external support. If the ship’s generators aren’t available or aren’t supplying power, the next source is the APU, which is a self-contained onboard generator used for start and for providing power when the engines aren’t supplying it. Only after both ship’s generators and the APU are unavailable would a Ground Power Unit be used. The GPU supplies power from an external ground source and is typically used on the ground when no onboard source can power the system, making it the last resort in the sequence.

Electrical power priority order is about using power sources in a defined sequence so the aircraft stays reliably powered while preserving options for emergencies. The highest priority is the ship’s generators because they are the primary, engine-driven sources tied directly to the aircraft’s electrical system and are available during normal operations. They provide stable, conditioned power to the essential and nonessential buses as needed, without needing external support. If the ship’s generators aren’t available or aren’t supplying power, the next source is the APU, which is a self-contained onboard generator used for start and for providing power when the engines aren’t supplying it. Only after both ship’s generators and the APU are unavailable would a Ground Power Unit be used. The GPU supplies power from an external ground source and is typically used on the ground when no onboard source can power the system, making it the last resort in the sequence.