Question

When does the checklist indicate the requirement to shut down the APU?

a) After landing and parking
b) Before takeoff
c) During mid-flight
d) During the pre-flight check

Answer 1

The checklist indicates the requirement to shut down the APU after landing and parking, to allow the plane to switch to ground power and air sources.

Step-by-step explanation:

The checklist in an aircraft typically indicates the requirement to shut down the Auxiliary Power Unit (APU) after the aircraft has landed and parked. Therefore, the correct answer is: a) After landing and parking. The APU is commonly used to provide electrical power and pneumatic pressure for aircraft systems while the main engines are not running, particularly during the pre-flight, boarding, and deplaning phases. Once the aircraft has reached its parking stand and connected to ground power and air sources, there should be no further need for the APU, and it can be shut down to conserve fuel and reduce wear.