Explore: Emergency Frequencies

distress. The frequencies are 121.5 MHz for civilian, also known as International Air Distress (IAD), International Aeronautical Emergency Frequency, or VHF

Cospas-Sarsat system no longer monitors the frequency. 243 MHz for NATO military aircraft emergency frequencies 406 MHz to 406.1 MHz is used by the Cospas-Sarsat

transmissions on the emergency frequencies, as most 406 MHz beacons are required to be equipped with 121.5 "homers." Furthermore, the 121.5 MHz frequency remains the

one meter. Frequencies immediately below VHF are denoted high frequency (HF), and the next higher frequencies are known as ultra high frequency (UHF). VHF

on the 121.5 MHz distress frequency and serves as a backup for ELT-type airborne beacons. For military users, the Emergency has a miniaturized transmitter

control may re-establish communications with NORDO aircraft by using emergency frequencies, voice features of NAVAIDs, or aviation light signals. In the event

490 kHz Aircraft emergency frequency Call for help – for emergency frequencies in current use Distress signal GMDSS Mayday Medium frequency radio propagation

officially designated emergency frequencies, from personal radio service operators, and report such calls to appropriate emergency authorities; (c) To promote

Mayday is an emergency procedure word used internationally as a distress signal in voice-procedure radio communications. It is used to signal a life-threatening

effectiveness because the affected stations usually change frequencies, put on additional frequencies and/or increase transmission power. Jamming has also occasionally