What is universally recognized as the emergency frequency?

The emergency frequency that is universally recognized is 121.5 MHz. This frequency is designated for use by aircraft in distress and is monitored by air traffic control and various ground stations. It is a vital resource that pilots can use to communicate emergencies, receive assistance, and alert authorities to their situation.

When an aircraft declares an emergency on this frequency, they can often receive immediate help from nearby aircraft or air traffic services. Additionally, this frequency is also used for emergency locator transmitters (ELTs) that automatically activate in a crash scenario, broadcasting signals to facilitate search and rescue operations.

Among the other frequencies provided, while they may serve various purposes, none have the same universal emergency recognition as 121.5 MHz. For example, 123.0 MHz is often used for common traffic advisory frequencies, 118.0 MHz is typically a standard VHF aviation communication channel, and 122.8 MHz is generally utilized for private airport traffic control, not emergencies.