What is "Mayday" used for in distress signals?

"Mayday" is a crucial term used in distress communications to indicate a life-threatening emergency. It conveys the urgency of a situation where there is an immediate threat to the safety of the aircraft, crew, or passengers. The term is internationally recognized and universally understood among pilots, air traffic controllers, and maritime operators, which helps ensure a swift and appropriate response to emergencies.

When "Mayday" is transmitted, it is typically followed by specific details about the nature of the emergency, the position of the aircraft, and the type of assistance required. This practice is essential for coordinating rescue efforts and ensuring that affected parties receive the necessary help as quickly as possible.

The other options pertain to different types of communication in aviation but do not carry the same weight of urgency that "Mayday" embodies. For instance, routine communications and non-critical situations would not invoke the use of "Mayday," as those situations do not involve an immediate threat to life or safety. Similarly, while requesting immediate landing clearance may be urgent, it does not indicate a life-threatening emergency, making it distinct from the use of "Mayday."