SHGM Call Center: 444 60 01

Processes for Assignment of Mode-S

Mode-S, as a model of the Secondary Surveillance Radar (SSR) developed through state-of-the-art techniques, enables to forward any details such as registration mark, location, altitude and speed of the aircraft as well as the estimated time of arrival of the same to the next report point, etc., to the air traffic control units.


Mode-S (S=Selective) is based on coding of the aircraft through the individual selective addressing in the width of 24 bit. An individual code is assigned for each aircraft. Individual SSR Mode-S address is assigned by the ICAO or the authorized institutions.

Use of Mode-S, which is put into practice as a resolution in respect of the heavy traffic particularly in the central area of Europe, has become mandatory in many countries due to its advantages. It is not mandatory to use Mode-S within the airspace of our country; however, process for assignment of Mode-S code, requested to be used at the airspaces requiring use of such code, is carried out by our Directorate General in accordance with the regulations on assignment of Mode-S code, which are specified in Volume III and Volume IV of Annex 10. 


Process of Application For Mode-S

  • The Operator/Owner fully completes the Mode-S Code Assignment Request Form, available on the official web page of our Directorate General, in respect of the aircraft, for which it obtains the registration mark, and applies for the Mode-S code through an official letter.
  • The applicant is required to send the reserve Letter of Registration/Certificate of Registration and the current Mode-S Code Assignment Request Form as attached to the official letter.
  • Service fee provided in the service tariff of our Directorate General is paid prior to the application, by taking into account the maximum take-off weight of the respective aircraft, and the original copy of the bank receipt is attached to the application form. 
  • In case of registration of the same aircraft to another registry upon de-registration, then the application is performed again.
  • It is mandatory that Mode-S Code Assignment Request Form is signed by the personnel approved by Form 4.
Our Directorate General calculates the Mode-S code based on the details specified in the Mode-S Code Assignment Request Form, and reports it to the applicant through an official letter.
Communications and Air Traffic Systems Directorate
Address Gazi Mustafa Kemal Bulvarı No:128/A 06570 Maltepe / ANKARA
Contact Person  Ufuk EROL
Tel (312) 203 60 20
Fax (312) 212 46 84