What term describes an aircraft that has failed to report and the appropriate time frame has elapsed?

The term "overdue" is used to describe an aircraft that has not made its required reports and the designated timeframe for those reports has passed. In aviation operations, particularly in air traffic control, there are established procedures and timelines for aircraft to report their position, status, or intentions. If an aircraft fails to report within the expected timeframe, it raises a concern for safety and operational continuity.

When an aircraft becomes overdue, it indicates that it should have communicated its status or position but has not done so. This situation prompts ATC to take specific actions to locate the aircraft, ensuring that it is not in distress or experiencing unforeseen difficulties.

In contrast, terms like "missing" generally refer to an aircraft that has not been located, whereas "unreported" may imply a lack of communication in a more general sense, without the specificity of time constraints. "Lost" often refers to scenarios where navigation has failed, but it does not specifically indicate a failure to report within a designated timeframe. Thus, "overdue" accurately reflects the critical context of time-sensitive communication in aviation operations.