What must be established prior to entering Class D airspace?

Before entering Class D airspace, it is essential to establish two-way communication with Air Traffic Control (ATC). Class D airspace is generally established around airports that have an airport traffic control tower, and the rules governing this type of airspace require pilots to communicate with ATC to ensure safe and organized traffic flow.

This communication is critical because it allows the pilot to receive instructions, advisories, and information about other traffic in the vicinity. Maintaining communication with ATC helps ensure that all aircraft are aware of one another, which is crucial for avoiding potential collisions. The requirement for two-way communication means that the pilot must be able to both transmit and receive messages from ATC, confirming their presence and intentions within the airspace.

Establishing visual contact with other aircraft, obtaining a clearance, or receiving flight following services might be beneficial or necessary in other contexts, but they are not prerequisites for entering Class D airspace. The key requirement is that the pilot must first communicate with ATC to ensure compliance with the regulations governing the use of that airspace.