What is 123.45 MHz?

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cpsTN

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I have tried to find this freq but to no avail. Since it is numerically interesting (12345), I assume it is a general Citizens Band-type freq for small aircraft. Generally on weekends, I hear chat between small aircraft from, what I assume, is the airport here in town that has an AFB (Sewart) associated with it. Is this assumption true?
 
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kny2xb

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I forgot where I read the usage originally. I have 123.450 labeled as "Long Range Air-to-Air". I believe that it's meant for trans-oceanic flights, but I have heard it used as a chat frequency without knowing where the aircraft talking were at that time. I'm on the west coast of Florida, so they could have been out over the Gulf, maybe not.

I found this: "VHF air to air frequency 123.45 MHz enable aircraft engaged in flights over remote and oceanic areas, out of range of VHF ground stations, to exchange necessary operational information
and to facilitate the resolution of operational problems."

As a side note, I also have programmed in: 122.750 which is designated as private fixed wing aircraft air-to-air, and 123.025 which is designated as helicopter [rotary wing] air-to-air.

So in general, I guess commercial flights use 123.450, and private planes use 122.750. Hopefully either a pilot or another aviation scannist can clarify this better.

Take care.
 

RadioDaze

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That didn't help. Everytime I try to read it, it tries to get me to register for something and won't let me go. I am not doing that. I DID do a bing search and have the general idea. Thank You.
I didn't have any issues with the web page. Sorry about that. Here's what it said, and the mods can remove it if it's a copyright problem.

*******
There are two frequencies that all pilots know by heart: 121.50 and 123.45. The first one is the emergency frequency that can be used at any time when safety of the flight is endangered. The second one… well… how to describe it… it’s piece of ambiguity.

ICAO Annex 10 states that “123.45 Mhz shall be designated for use as an Air-to-Air communications channel to enable aircraft engaged in flights over remote and oceanic areas, out of range of VHF ground stations, to exchange necessary operational information and to facilitate the resolution of operational problems“. As all ICAO documents, this is a recommendation, which can be overruled by local laws.

Most of Europe is not continental nor remote, but several pilots do use it as a chat frequency. The UK NATS published an AIC (16/2003 Pink 53) to remind pilots that this frequency is not for general use by pilots, as it is officially allowed to some helicopters companies. Moreover using 123.45 in a UK FIR can result in interference at other places.

Germany defined 122.80 as a “chat frequency”, and 123.45 is also used by Bangalore Tower (India). When googling it, I found many references mentioning this frequency being recognized as air-to-air frequency in the US, but no official confirmation. Finding the official chat frequency (if any) in the national AIPs or in the standardized Jeppesen manuals is not easy.

With such a complicated situation (referred to as a “mess” by some NATS collaborators), it’s not surprising that some urban legends exists about it in the flying community. The following dialog supposedly happened in Frankfurt:

“US-Airforce C-130: TWR tell 747 in front of us to call us on 123.45
TWR: XX777 would you mind calling C-130 on 123.45?
xx777: Sorry TWR, we do not talk on 123.45, we are professional pilots
US-Airforce C-130: OK, TWR tell those professional pilots they still have the gear pins in!”
(The pins are security locks put on ground to avoid unwanted retraction)

Now, I’d like to know what is your personal use of 123.45. No matter if you’re an airline pilot using it on the Atlantic, or a club-pilot using it to chat with friends, share your habits in comments.
*******
 

nd5y

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So in general, I guess commercial flights use 123.450, and private planes use 122.750. Hopefully either a pilot or another aviation scannist can clarify this better.
It depends on your location. Lately In my area I have been hearing airline pilots on 122.775 more than 123.45. 122.825 and 122.875 are also commonly used.

VHF com radios can operate on any frequency from 118.0-136.975 so some pilots will use whatever frequency they want or don't get chased off of by legitimate users.

Here is the chart of what is allowed in the US.
Electronic Code of Federal Regulations:
 
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WouffHong

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123.45

I have tried to find this freq but to no avail. Since it is numerically interesting (12345), I assume it is a general Citizens Band-type freq for small aircraft. Generally on weekends, I hear chat between small aircraft from, what I assume, is the airport here in town that has an AFB (Sewart) associated with it. Is this assumption true?
Some DO consider it AIrcraft Channel 19 (CB) - The stuff one picks up sometimes is downright weird! :) :roll: :roll: :wink:

Wouff
 

mass-man

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Interesting...for many years the morning radio traffic helicopters here in DFW used 123.45 to chat and advise each other of traffic snarls as they couldn't all be in the same place at the same time. I will have to listen on Monday and see if that is still true.
 

cpsTN

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I heard a chat between two aircraft one Saturday morning (on 123.45 MHz) as two private planes flew over. I assumed it was them but it could have been a coinsedence. Everything I have heard on 123.45 has been chat of one type of the other. I will do a freq search on the scanner and see what I can hear in the 120-125 range. Thanks guys.
 

nd5y

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Interesting...for many years the morning radio traffic helicopters here in DFW used 123.45 to chat and advise each other of traffic snarls as they couldn't all be in the same place at the same time. I will have to listen on Monday and see if that is still true.
Unless they changed recently, the traffic reporter aircraft had certain FAA approved flight paths that they had to follow.

The air to air coordination frequencies used were 122.775 west of state highway 360 and 123.025 east of state highway 360. I have never heard of them using 123.45.

I don't know how many traffic reporting aircraft are left in the DFW area. A few years ago at least some if not all of the companies that operated the aircraft stopped doing it.
 

ff-medic

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I have tried to find this freq but to no avail. Since it is numerically interesting (12345), I assume it is a general Citizens Band-type freq for small aircraft. Generally on weekends, I hear chat between small aircraft from, what I assume, is the airport here in town that has an AFB (Sewart) associated with it. Is this assumption true?


Google is your friend.

" or, as a back-up, the VHF inter-pilot air-to-air frequency 123.45)."

Reference = www.faa.gov/.../PilotBulletin_WxDevProc_Both_Formats_11Apr08_SMS.doc

And I found FAA as well as FCC documents that 123.45 is the inter-pilot air to air freq.

FF-Medic !!!
 

jaymatt1978

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Interesting thread going here. Let me preface this by saying I live in Northern NJ (north of NYC). One day I was listening to123.45 and two pilots were going at it,just chatting shooting the breeze. Usually convesations on 123.45 arre brief, but these guys were going at it for at least a half hour. Finally one pilot said something to the affect of " I'm just passing over Albany" and the other mentioned he was south of Atlantic City!!!!
 
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