When should a message be transmitted immediately after call up?

Transmitting a message immediately after call up is most effective when the message is short. Short messages can be conveyed quickly, ensuring that communication is efficient. This allows the controller to provide timely instructions or information without unnecessary delays, which is crucial in maintaining safety and operational flow in non-radar environments.

When the message is concise, it minimizes the likelihood of misunderstanding and allows the recipient to process the information swiftly. In contrast, longer messages may require more time to convey and could lead to interruptions in the communication flow, potentially adding confusion or delaying critical instructions. Thus, brevity plays a vital role in ensuring that all communications are clear and rapid in high-paced air traffic scenarios.