220.127.116.11.1Messages handled entirely by the aeronautical mobile service shall comprise the following parts in the order stated:
a) call indicating the addressee and the originator (see 18.104.22.168.3);
b) text (see 22.214.171.124.2.1.1).
Note. The following examples illustrate the application of this procedure:
(call) NEW YORK RADIO SWISSAIR ONE ONE ZERO
(text) REQUEST SELCAL CHECK
(call) SWISSAIR ONE ONE ZERO NEW YORK RADIO
(text) CONTACT SAN JUAN ON FIVE SIX
126.96.36.199.2 Messages requiring handling by the AFTN for part of their routing and similarly messages which are not handled in accordance with predetermined distribution arrangements (see 188.8.131.52) shall be composed as follows:
184.108.40.206.2.1 When originated in an aircraft: 1) call (see 220.127.116.11.3);
2) the word FOR;
3) the name of the organization addressed;
4) the name of the station of destination;
5) the text.
18.104.22.168.2.1.1 The text shall be as short as practicable to convey the necessary information; full use shall be made of ICAO phraseologies.
Note. The following example illustrates the application of this procedure:
(call) BOSTON RADIO SWISSAIR ONE TWO EIGHT
(address) FOR SWISSAIR BOSTON
(text) NUMBER ONE ENGINE CHANGE REQUIRED
22.214.171.124.2.2 When addressed to an aircraft. When a message, prepared in accordance with 4.4.2, is retransmitted by an aeronautical station to an aircraft in flight, the heading and address of the AFTN message format shall be omitted during the retransmission on the aeronautical mobile service.
126.96.36.199.2.2.1 When the provisions of 188.8.131.52.2.2 are applied, the aeronautical mobile service message transmission shall comprise:
a) the text [incorporating any corrections (COR) contained in the AFTN message];
b) the word FROM;
c) the name of the originating organization and its location (taken from the origin section of the AFTN message).
184.108.40.206.2.2.2 PANS. When the text of a message to be transmitted by an aeronautical station to an aircraft in flight contains approved ICAO abbreviations, these abbreviations should normally be converted during the transmission of the message into the unabbreviated words or phrases which the abbreviations represent in the language used, except for those which, owing to frequent or common practice, are generally understood by aeronautical personnel.
Note. The abbreviations which constitute the exceptions mentioned in 220.127.116.11.2.2.2 are specifically identified in the abbreviations encode sections of the PANS-ABC (Doc 8400).
Source: ICAO Annex 10.2