What must be done when transmitting non-essential messages to ATC?

When transmitting non-essential messages to Air Traffic Control (ATC), it is crucial to limit messages to those that contribute to safety. This principle ensures that communication is focused and relevant, aiding in the effective management of air traffic and minimizing unnecessary communication that could potentially distract controllers or disrupt the flow of traffic.

Maintaining clear and concise communication helps prevent confusion and allows ATC to prioritize essential operational communications. By focusing on messages that enhance safety, non-essential communications can support situational awareness without overwhelming or cluttering the airways, thereby facilitating a more organized and efficient airspace system.

The other choices might not align with established procedures in air traffic communication. For example, providing a brief overview of the situation or only communicating during emergencies could lead to unnecessary distractions or miscommunications. Transmitting only when cleared by the aircraft may not be feasible or appropriate for routine non-essential messages. The emphasis on safety remains paramount in all forms of communication with ATC.