What does ALNOT signify in search and rescue operations?

ALNOT, which stands for Alert Notice, is specifically utilized in search and rescue operations to indicate a situation wherein all attempts to contact an aircraft have been unsuccessful after issuing an INREQ (Information Request). This notice serves as a crucial marker that alerts search and rescue authorities to the potential distress of the aircraft, triggering necessary actions to locate and assist it.

This makes it an essential component in the search and rescue protocol, where timely response can be the difference in ensuring the safety of individuals aboard the aircraft. The understanding of ALNOT as an important operational alert highlights the seriousness and urgency in search and rescue contexts, distinguishing it from other alerts that serve different purposes, such as those focused on airspace violations or aircraft performance issues.