What frequency is also utilized by aircraft for emergency locator beacons?

The frequency utilized by aircraft for emergency locator beacons is 121.5 MHz. This frequency is recognized globally for emergency distress communications. Aircraft use emergency locator transmitters (ELTs), which are specifically designed to transmit signals on 121.5 MHz when activated, indicating an emergency situation.

The rationale for using this specific frequency is that it is monitored by search and rescue organizations around the world, including the Coast Guard, ensuring that alerts are received and acted upon promptly.

While 406 MHz is also used for emergency beacons, particularly by newer ELTs, it primarily provides improved accuracy and is intended for satellite monitoring. However, 121.5 MHz has historical significance and remains a default emergency frequency.

The other frequencies listed, such as 164.5 MHz and 148.1 MHz, do not serve the same purpose for emergency locator beacons, making 121.5 MHz the definitive choice for emergency signaling in aviation.