Do you know how to use 123.45 ?
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 recomnendation, 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 interefence at other places (click here for more information).
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.
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4 Comments, Comment or Ping
Matt
I’ve mainly used it coordinate flights of 2 or more aircraft (ok so the most I’ve ever done is two…). We take off separately and then join up enroute and we can talk about things we see. One time we spotted something “suspicious” off the coast, near the area where TWA800 had crashed back in the 90’s.
I’ve also used it to get inflight PIREPs from other pilots without going through Flight Service here in the U.S. You can transmit blind to anyone in the area and sometimes you might get some good information about the weather up ahead.
Jun 4th, 2008
Chris
I’ve heard it being used here in Australia for chatting, and occasionally co-ordinating formation flying.
Jun 4th, 2008
Julien
I looked up what the ERSA has to say about 123.45 in Australia. Short version: “Communications between aircraft on this frequency are restricted to the exchange of information relating to aircraft operations”. Of course the operational reality is a tiny bit different.
I put the full text in a blog post here:
http://makingtimeforflying.blogspot.com/2008/06/plastic-pilot-recently-published-post.html
Julien.
Jun 6th, 2008
PlasticPilot
Thank you all for these complements, and Julien, thank you for the link back from your blog
Jun 6th, 2008
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