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Is 121.5 an Emergency Freq for Logan or Airplanes?

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#1
Hello everyone,

Is 121.5 an emergency freq for airplanes? I've seen it called an emergency freq on some sites a while back...

Though I've never heard it used as such... actually... I've never heard it used...

When ever there is an emergency at Logan I hear the pilots talking to the tower, approach and MassPort, never 121.5.

Let me know if I should delete this out of my Logan bank.


Thanks!
 

Gezelle007

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#2
121.5 is the international emergency channel for all aircraft. It is known as "guard". The military version of this frequency is 243.0. I do believe they are harmonics of each other.
 
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Sumter County, GA, USA
#3
Eastie,

I suggest you keep 121.500 (& 243.000) programmed in your favorite aviation bank. If that's your favorite part of the hobby (e.g., aviation scanning), then use 121.5 as a priority channel.

If ATC cannot reach the intended aircraft, they will ask other planes on frequency to try to raise a specific aircraft on "GUARD." Of course, there is always the risk of having a true aviation emergency.

I keep both 121.5 & 243.0 in my active scan lists, as I live and travel near a number of major airports and military aviation training areas.

Enjoy,
 

zerg901

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#4
I think that most air traffic control towers keep one radio listening on 121.50. I am not sure if the FAA enroute centers do or not. If a plane has 2 air band radios, I think they usually keep one tuned to 121.50. 121.50 kinda serves as a international backup freq. If military fighter jets are trying to contact a civilian aircraft, I am pretty sure that procedures call for them to use 121.50. Peter Sz
 

Lynch_Christopher

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#5
I think that most air traffic control towers keep one radio listening on 121.50. I am not sure if the FAA enroute centers do or not. If a plane has 2 air band radios, I think they usually keep one tuned to 121.50. 121.50 kinda serves as a international backup freq. If military fighter jets are trying to contact a civilian aircraft, I am pretty sure that procedures call for them to use 121.50. Peter Sz
Having friends who work at Boston Center the FAA enroute centers I believe monitor 121.500.
 
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#6
Having friends who work at Boston Center the FAA enroute centers I believe monitor 121.500.
Perhaps you could ask him how often they actually hear something on that channel.

Although 121.5 is the emergency channel, in most cases the plane with an emergency is already in contact with a controller on another frequency and they stay on that freq.


121.5 is also used by obsolete ELTs (emergency locator transmitters) and by some homing beacon systems used by scuba divers, along with some other types of users. For a couple decades now, all new EPIRBs and ELTs have used 406MHz, and I think that satellite monitoring of 121.5MHz has ceased.
 
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#7
Correct. Why Dial 9-1-1 when you have already dialed the 9 digit Non-Emergency # to report your issue. So why change freq's if you already are in-contact.

121.5000 is used, if contact can not be make with the already connected channel paths.

Perhaps you could ask him how often they actually hear something on that channel.

Although 121.5 is the emergency channel, in most cases the plane with an emergency is already in contact with a controller on another frequency and they stay on that freq.


121.5 is also used by obsolete ELTs (emergency locator transmitters) and by some homing beacon systems used by scuba divers, along with some other types of users. For a couple decades now, all new EPIRBs and ELTs have used 406MHz, and I think that satellite monitoring of 121.5MHz has ceased.
 
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