FAA Aircraft Dispatcher Practice Exam

When the Auxiliary Power Unit (APU) is inoperative, a critical consideration is to ensure that external electrical and pneumatic power is available. The APU is responsible for providing power and air for starting engines, as well as maintaining systems when the aircraft is on the ground. If the APU is not functioning, the aircraft will need an alternative means of obtaining these essential services.

External power units can supply the necessary electrical power for the aircraft's systems and cockpit, while external pneumatic sources are required for engine start when the APU is unavailable. Without this support, the aircraft could be unable to start or maintain its systems, leading to delays or operational issues.

Additionally, while ensuring enough fuel is available, checking the flight plan accuracy, and notifying management of the APU issue are all important tasks, they do not address the immediate need for the aircraft to have power and air for engine start and system operations. Thus, ensuring the availability of external electrical and pneumatic power is paramount when the APU is inoperative.