# Commission Implementing Regulation (EU) No 923/2012 of 26 September 2012 laying down the common rules of the air and operational provisions regarding services and procedures in air navigation and amending Implementing Regulation (EU) No 1035/2011 and Regulations (EC) No 1265/2007, (EC) No 1794/2006, (EC) No 730/2006, (EC) No 1033/2006 and (EU) No 255/2010 (Text with EEA relevance), Division SERA.14050: Radiotelephony call signs for aircraft

Extent: E+W+S+N.I.

(a) Full call signs:
An aircraft radiotelephony call sign shall be one of the following types:
(1) Type (a) the characters corresponding to the registration marking of the aircraft; or
(2) Type (b) the telephony designator of the aircraft operator, followed by the last four characters of the registration marking of the aircraft;
(3) Type (c) the telephony designator of the aircraft operator, followed by the flight identification.
(b) Abbreviated call signs:
The aircraft radiotelephony call signs shown in point (a), with the exception of Type (c), may be abbreviated under the circumstances prescribed in point SERA.14055(c). Abbreviated call signs shall be in the following form:
(1) Type (a) the first character of the registration and at least the last two characters of the call sign;
(2) Type (b) the telephony designator of the aircraft operator, followed by at least the last two characters of the call sign;
(3) Type (c) no abbreviated form.

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Source: https://www.legislation.gov.uk/eur/2012/923/annex/section/14/division/SERA.14050 (the official version)
Page: https://openlegislation.uk/eu-regulation-2012-923/annex/section-14/division-SERA.14050
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.