When should a code change be requested?

The appropriate time to request a code change is when an aircraft is in your area of responsibility. This ensures that the flight is under your control and that you are equipped to manage its safety and operational needs. When an aircraft enters your designated airspace, you have a direct responsibility to monitor and assist it, thus necessitating the appropriate code change to enhance situational awareness and maintain communication with the aircraft.

Requesting a code change solely when it is convenient could lead to gaps in communication or oversight, potentially compromising safety. Similarly, requesting a change immediately after a flight plan is filed can lead to confusion, as the aircraft may still be outside of your jurisdiction and not yet under your procedural control. Lastly, requesting a code change before any radar service requests does not align with the operational protocols that prioritize communication and situational awareness only after an aircraft is within your area of responsibility.