When parked, which power sources supply electrical power to the aircraft?

Prepare for the Delta 737 PA-LOD Exam with flashcards and multiple choice questions. Each question includes hints and explanations, ensuring you're ready for exam day!

Multiple Choice

When parked, which power sources supply electrical power to the aircraft?

On the ground, the aircraft’s electrical power comes from one of a few sources, and the system is designed to use whichever is available. External power from a ground power unit or fixed facility can power the aircraft’s electrical buses without running the engines. If external power isn’t connected, the APU can be started to supply electrical power and support systems while the engines stay off. If neither external power nor the APU is providing power, the aircraft relies on its battery to support essential loads needed to keep critical avionics and basic flight-deck functions alive for a limited time. That combination—external power or the APU as the primary sources, with the battery providing essential loads if neither is available—is why the best answer is the one that recognizes all three sources.

On the ground, the aircraft’s electrical power comes from one of a few sources, and the system is designed to use whichever is available. External power from a ground power unit or fixed facility can power the aircraft’s electrical buses without running the engines. If external power isn’t connected, the APU can be started to supply electrical power and support systems while the engines stay off. If neither external power nor the APU is providing power, the aircraft relies on its battery to support essential loads needed to keep critical avionics and basic flight-deck functions alive for a limited time.

That combination—external power or the APU as the primary sources, with the battery providing essential loads if neither is available—is why the best answer is the one that recognizes all three sources.

More practice questions