Which frequency is designated for distress communications under PRC-149?

The frequency designated for distress communications under PRC-149 is 121.5 MHz. This frequency is part of the aeronautical emergency frequency allocations and is widely recognized as the international distress frequency for civil aviation. It is crucial for pilots and air traffic control to monitor this frequency, as it is often used for emergency situations where immediate assistance is required.

While other frequencies such as 406.025 MHz are used in emergency beacons and satellite communications for distress, 121.5 MHz has been historically significant and remains a key frequency for initial distress communications. It provides immediate access to emergency services and can be monitored by aircraft, ground stations, and search and rescue teams. Understanding this frequency is vital for effective communication in emergency scenarios when rapid response is necessary.