What must be accomplished before entering any class D airspace?

Establishing radio communication with Air Traffic Control (ATC) is essential before entering any Class D airspace. Class D airspace is typically surrounding an airport with a control tower, and it is crucial for maintaining safe flight operations. Before entering this airspace, pilots must check in with ATC to ensure they are aware of your intentions and to receive any necessary instructions or traffic advisories. This requirement helps ensure the safety and efficiency of air traffic operations, coordinating the activities of multiple aircraft in close proximity.

The other options may be relevant to flight operations or safety but are not mandatory prerequisites for entering Class D airspace. For example, while obtaining a flight plan is essential for certain types of operations, particularly for instrument flight rules (IFR), it is not required for every flight, especially VFR (Visual Flight Rules) flights. Similarly, landing fees may be applicable at some airports, but they are not a requirement for entering the airspace itself. A pre-flight inspection is a crucial safety measure that every pilot must perform, but it is distinct from communication protocols necessary for entering controlled airspace.