What is the frequency at which Emergency Locator Transmitters (ELTs) transmit?

Emergency Locator Transmitters (ELTs) are specifically designed for use in aviation to aid in search and rescue operations following an aircraft accident. The standard frequency at which ELTs transmit is 121.5 MHz. This frequency was widely used for distress signaling and is monitored by air traffic control and search and rescue agencies.

The choice of 121.5 MHz for ELTs is significant because it is part of the integrated global distress system, which allows for better coordination and a quicker response in emergency situations. This frequency is also utilized by various emergency equipment, making it a universal standard in aviation safety protocols.

Other frequencies listed, such as 123.45 MHz, 132.3 MHz, and 127.0 MHz, are not designated for emergency distress signals and serve different communication purposes within the aviation community. They are used for air-to-air or air-to-ground communication among pilots and air traffic controllers but do not have the same emergency signaling function as 121.5 MHz.