Transponder codes may be changed without coordination upon initial contact if what condition is met?

Transponder codes may be changed without coordination upon initial contact when both facilities are operating under ERAM (En Route Automation Modernization). This system allows for real-time tracking and communication between air traffic control facilities. When both facilities are utilizing ERAM, it indicates a shared platform that facilitates immediate information exchange about aircraft status, sequencing, and tracking.

In this situation, the facilities have access to up-to-date data and can efficiently manage transponder code assignments without the need for prior coordination. This capability streamlines operations and enhances situational awareness for controllers, allowing them to focus on other critical aspects of air traffic management.

The other conditions presented do not inherently provide the necessary infrastructure or communication capabilities to change transponder codes without coordination. For example, shared frequency, being in the same state, or having completed pre-flight checks does not guarantee the seamless data exchange and operational efficiency that ERAM provides. Therefore, operating under ERAM is the key condition that permits this action.