What does the APU do on the ground?

What does the APU do on the ground?

• A. It provides electricity and air conditioning while the aircraft is on the ground
• B. It powers the main propulsion system
• C. It controls the aircraft's flight surfaces
• D. It provides emergency landing gear retraction

Answer: (A)

The APU’s job on the ground is to provide the aircraft with electrical power and conditioned air while the main engines are not running. This lets you run cabin climate control, lights, avionics, and other systems without needing ground power or the engines, and it can also supply bleed air to start the engines. It isn’t responsible for powering the engines, moving flight surfaces, or retracting landing gear, which are handled by other systems. That’s why the description of supplying electricity and air conditioning on the ground is the best fit.

The APU’s job on the ground is to provide the aircraft with electrical power and conditioned air while the main engines are not running. This lets you run cabin climate control, lights, avionics, and other systems without needing ground power or the engines, and it can also supply bleed air to start the engines. It isn’t responsible for powering the engines, moving flight surfaces, or retracting landing gear, which are handled by other systems. That’s why the description of supplying electricity and air conditioning on the ground is the best fit.