What is the primary purpose of the APU generator?

What is the primary purpose of the APU generator?

• A. To supply pneumatic power for cabin pressurization
• B. To provide electrical power only when external power is connected
• C. To supply electrical power (and possibly pneumatic power via APU) when main generators are unavailable or on the ground
• D. To recharge the batteries during flight

Answer: (C)

The main idea is that the APU generator is a self-contained power source for the aircraft. Its primary job is to provide electrical power to the airplane’s systems when the main generators aren’t available—such as when the engines aren’t running or when external power isn’t connected on the ground. It can also supply pneumatic power via bleed air if the aircraft design uses that capability, for tasks like starting engines or supporting certain pneumatic systems when needed. It isn’t the routine source for cabin pressurization, and its role isn’t to recharge batteries during flight as the primary function. In short, the APU generator keeps the aircraft powered and operable when the primary power sources aren’t in use, and can provide bleed air if required.

The main idea is that the APU generator is a self-contained power source for the aircraft. Its primary job is to provide electrical power to the airplane’s systems when the main generators aren’t available—such as when the engines aren’t running or when external power isn’t connected on the ground. It can also supply pneumatic power via bleed air if the aircraft design uses that capability, for tasks like starting engines or supporting certain pneumatic systems when needed. It isn’t the routine source for cabin pressurization, and its role isn’t to recharge batteries during flight as the primary function. In short, the APU generator keeps the aircraft powered and operable when the primary power sources aren’t in use, and can provide bleed air if required.