Coordination of secondary airport departures may be accomplished by interphone communications or 4th line data entry. Which methods are appropriate?

• A. Only voice radio
• B. Interphone or 4th line data entry
• C. Email and memo
• D. Visual signals

Answer: (B)

Coordinating departures at a secondary airport needs both a real-time, direct communication channel and a dependable way to record the details in the system so everyone is on the same page. Interphone is the immediate, two-way voice link that lets the controller at the primary facility and the staff at the secondary airport discuss timing, runway use, sequencing, and any special instructions as events unfold. That immediacy is crucial for making quick adjustments and reducing the chance of miscommunication.

The fourth line data entry provides the necessary record-keeping and visibility in the automation environment. By entering the coordination details into the data line, the departure instructions, clearances, and timing become part of the shared, auditable record that can be seen by all involved parties and used to align the flight plan with the operational workflow. This combination ensures that the communication is both timely and documented, supporting traceability and coordination across the system.

Email and memo are too slow for real-time operations, and visual signals aren’t reliable or clear enough for disciplined airspace coordination. Relying on voice radio alone lacks the formal data record and system integration needed for coordinated departures.