FAA Military Competency Practice Exam

What designated airspace associated with an airport becomes inactive when the control tower at the airport is not in operation?

1. Class C

2. Class D

3. Class E

4. Class A

The correct answer is: Class D

The correct response is based on the operational status of the control tower at an airport, particularly Class D airspace. Class D airspace is specifically designed as the controlled airspace associated with airports that have an operational control tower. When the control tower is not in operation, the Class D airspace becomes inactive, thereby reverting to the underlying airspace classification, usually Class E or G, depending on the area. This is crucial for pilots to know because the operational procedures and regulations they must follow differ significantly under each class of airspace. In contrast, Class C and Class A airspace do not become inactive simply due to the control tower's status. Class C airspace remains active as it is associated with larger airports and is generally managed by air traffic control even when the tower is not operational. Class A airspace, which extends from 18,000 feet MSL up to and including 60,000 feet, is active all the time and requires specific qualifications and equipment to operate within it. Class E airspace, on the other hand, is generally uncontrolled and is available for use regardless of the control tower's status. Thus, understanding the dynamics of Class D airspace is essential for safe and compliant operation around airports with changing tower statuses.