Mode 5 frequency supportability

Helping with the implementation of military IFF Mode 5.

At EUROCONTROL, we provide support to military and state actors in their efforts to implement military IFF Mode 5 while preventing harmful interference to civil air traffic management.


In our efforts, EUROCONTROL and NATO jointly developed a guideline to help civil and military entities involved in the assessment of frequency supportability. The purpose of this document is to:

  • provide guidance to civil and military organisations involved in the national and international process of assessment of frequency supportability for the use of Military Secondary Surveillance Radar/Identification System IFF Mode 5;
  • prevent harmful interference to civil Air Traffic Management (ATM) systems while enabling the military to conduct required peacetime testing and operational training using IFF Mode 5.

The joint development of this document is based on the Memorandum of Cooperation (MoC) of 8 May 2003 between EUROCONTROL and NATO, and in particular its Articles 1.2 (g) and 4, and the related Practical Working Arrangements of 17 February 2014 (Annex 1, paragraph a).

The guideline can be received upon request and prior approval of the designated NATO or EUROCONTROL contact persons.

Request support

Contact us to learn more and request support (via our contact bubble).