guard frequency

guard frequency

An emergency VHF/UHF (very high frequency/ultrahigh frequency) channel monitored as a secondary frequency by all air and ground stations in a geographical area. The guard frequencies 121.5, 243 and 406 MHz are reserved around the world and are known as international aeronautical emergency frequencies. They should not be used for normal voice messages or general conversation.
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Due to the orthogonality of the carriers, adjacent single band channels can be placed side-by-side without need for guard frequency interval between them [11].
We heard Red Crown making calls on guard frequency to another unidentified aircraft, which made it difficult to hear our CO.
The local controller immediately saw the problem and got on the guard frequency (a frequency that can be heard by all aircraft no matter what other frequency they're on) and told Pacer 19 to hold short of the runway Pacer 19 was able to stop as the F-15s continued their takeoffs.
With that in mind, now is a good time to remind readers that FAA Notices to Airmen (Notams) for years have required all operators, if capable, to monitor the so-called Guard frequency (121.
We could communicate with the ship over guard frequency, and at roughly 20 miles out, we received the ship's TACAN signal.
NATCA alleged that "controllers at Oakland Air Route Traffic Control Center last Sunday were deliberately prevented from monitoring the distress calls from a small plane in trouble" when the supervisor cut the sound on the loudspeaker system tuned to the guard frequency (121.
As we climbed higher, we picked up an E-2C on guard frequency.
The pilot of the airattack aircraft tried to contact the pilot of the Navy aircraft on VHF guard frequency (121.
I asked the HAC to raise the landing gear and to get out a Mayday call on guard frequency.
My COTAC, bless him, had pulled out his PRC-90 and had tried to talk on guard frequency.
As I switched off of guard frequency back to Washington Center, the controller frantically called for me to contact the next ATC sector.