What is one role of the APU during ground operations?

The Auxiliary Power Unit (APU) plays a critical role in providing air conditioning during ground operations. When the aircraft is on the ground and the main engines are not running, the APU delivers the necessary electrical power and bleed air to maintain climate control within the cabin. This is essential for ensuring the comfort of passengers and crew members, especially in extreme weather conditions.

In addition to providing air conditioning, the APU also supports other functions, such as powering essential systems and starting the main engines, but during ground operations, its air conditioning function is particularly important. When the aircraft is stationary and using ground power, proper temperature regulation is essential, which highlights the importance of the APU in maintaining an optimal operational environment before takeoff.