[Jenny]

At the moment if you arrive at an unmanned airfield and use the radio frequency you have to talk to 'ground' and any other aeroplane has to do the same... would make a lot more sense if they could talk directly to each other.

It would also be very nice to have an official air to air frequency.

[Keef]

I think that if you use "Safetycom" you can talk to "Puddletown Traffic". What you can't do is talk to G-BEJW.

If you're flying in Germany, you can talk air-air: there are frequencies set aside for that. In other countries, 123.45 has been used for that since time immoral.
I had heard rumours that 123.45 had been approved in the UK for that purpose, but I've heard that rumour so often in the past 30 years that I'm not sure. I think the real reason is that Ofcom will want their £100,000 for the frequency before you will be allowed to use it.

[Old Pilot]

Everyone uses 123.45.

Easy to remember.

[Jenny]

It was the 'official' bit I was interested in... I have no problem with the 'unofficial' bit!

[Paul_Sengupta]

Regarding air to air and 123.45...

AIC: Y 133/2012 04-OCT-2012
USE OF FREQUENCY 123.45 MHz IN THE UK

Cancels AIC Y 044/2010 (this was the original announcement, very similar to this AIC)

1 Introduction

1.1 ICAO Annex 10 (Aeronautical Telecommunications) Volume 5 designates frequency 123.45 MHz for use as a VHF 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 facilitate the resolution of operational problems.

1.2 This Circular is issued to remind pilots that use of the air-to-air channel can cause interference to and from aircraft using the same frequency for air-ground communications, and that pilots should adhere to the published procedures for the frequency.

2 Procedures

2.1 Procedures for the use of 123.45 MHz are as follows:

a. In remote and oceanic areas out of range of VHF ground stations, the air-to-air VHF communications channel on frequency 123.45 MHz shall only be used by aircraft fitted with communication equipment meeting the characteristics described in Annex 10 Vol 3, Part 2 Chapter 2. Amongst other requirements the aircraft radio must be capable of 25 kHz channel spacing.

b. Pilots shall only use frequency 123.45 MHz for the exchange of operational information and to facilitate the resolution of operational problems.

c. Pilots shall establish air-to-air communications on frequency 123.45 MHz by either a directed call to a specific aircraft or a general call, using the RTF phraseology shown at Annex A.

d. Pilots using 123.45 MHz as an air-to-air communication channel shall ensure that adequate watch is maintained on designated ATS frequencies, any other mandated frequencies and, where required by company operating procedures, the frequency of the aeronautical emergency channel.


Phraseology for use on Frequency 123.45 MHz

1 As an aircraft may be maintaining watch on more than one frequency, the initial call should include the identification ‘Interpilot’.

2 For use when making a directed call to a specific aircraft:
‘(Callsign of aircraft being called) (Callsign of calling aircraft) interpilot, do you read.’

3 For use when making a general call:
‘Any aircraft vicinity of (specific position) (callsign of calling aircraft) interpilot (any additional appropriate information).’