How is an aircraft defined as overdue?

An aircraft is defined as overdue when it cannot be contacted by either radio or radar and 30 minutes have passed since its Estimated Time of Arrival (ETA). This definition is critical for air traffic controllers and search and rescue operations because it establishes a standard timeframe for assessing the status of an aircraft that is expected to arrive at a specific point but has not done so.

The rationale behind the 30-minute period is that it allows enough time for potential delays or minor communication issues while also ensuring that a timely response can be orchestrated in case there is a genuine issue with the aircraft. Once this timeframe elapses without contact, appropriate actions can be initiated to locate the aircraft and ensure the safety of those on board.

The choice of 30 minutes strikes a balance between allowing for reasonable delays and ensuring proactive measures are taken to account for potential emergencies. Thus, this timeframe is a well-established guideline within aviation safety protocols.