In the absence of core processing, communication with Ground Control/Control Tower should use which system?

The correct choice is related to the specific communication protocols utilized in aviation, especially in the context of communicating with Ground Control or Control Tower when core processing is not available.

UHF (Ultra High Frequency) radios are crucial for aviation communication, particularly for air traffic control operations. UHF 3 is designated for specific communication needs that align well with ground control and tower communication functions.

In instances where the primary systems may be down or unavailable, relying on the designated UHF frequency for these interactions ensures that pilots maintain compliance with communication protocols essential for safe operations on the ground and during takeoff or landing procedures.

Utilization of UHF 3 specifically allows for proper alignment with air traffic frequencies that ground control operates on, ensuring clarity and maintaining operational communication standards. This is vital for pilots to receive instructions, relay their status, and navigate any ground or runway operations effectively in the absence of core processing.