# Commission Implementing Regulation (EU) No 1207/2011 of 22 November 2011 laying down requirements for the performance and the interoperability of surveillance for the single European sky (Text with EEA relevance), Division 2: The following data items, where available on a digital bus, shall be transmitted by the transponder as requested by the ground-based surveillance chain, via the Mode S protocol and in accordance with the formats specified in ICAO document 9871 (2 nd edition):

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

(a) MCP/FCU selected altitude;
(b) roll angle;
(c) true track angle;
(d) ground speed;
(e) magnetic heading;
(f) indicated airspeed (IAS) or mach number;
(g) vertical rate (barometric or baro-inertial);
(h) barometric pressure setting (minus 800 hectoPascals);
(i) track angle rate or true airspeed if track angle rate is not available.

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Source: https://www.legislation.gov.uk/eur/2011/1207/annex/II/part/3/division/2 (the official version)
Page: https://openlegislation.uk/eu-regulation-2011-1207/annex-II/part-3/division-2
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.