Standardisation of ADS-B and WAM

EUROCONTROL is a co-leader of the ADS-B & WAM standardisation activities. The standards and related certification and guidance material make for a solid baseline for ADS-B Out, initial ADS-B In and WAM based operations. The ADS-B standardisation work is carried out by EUROCAE WG 51 and often jointly with RTCA SC-186. These standards have been delivered so far:


  • ADS-B Out for use in Non-Radar Airspace (ADS-B NRA, ED-126 / DO-303);
  • ADS-B Out for use in Radar Airspace (ADS-B RAD, ED-161 / D0-318);
  • ADS-B Out for Airport Surface Surveillance (ADS-B APT, ED-163 / DO-321);
  • Minimum Operational Performance Standards (MOPS) for 1090 MHz extended squitter ADS‑B (ED-102A / DO-260B);
  • Technical specification for a 1090 MHz extended squitter ADS-B ground system (ED-129B).


  • In-Trail Procedure in oceanic airspace (ITP, ED-159 / DO-312);
  • Visual Separation on Approach (VSA, ED-160 / DO-314);
  • Enhanced Traffic Situation Awareness during Flight Operations (AIRB, ED-164 / DO-319);
  • Enhanced Traffic Situation Awareness on the Airport Surface (SURF, ED-165 / DO-322);
  • Traffic Situation Awareness with Alerts (TSAA, ED-232 / DO-348);
  • CDTI Assisted Visual Separation (CAVS, ED-233 / DO-354);
  • Flight Deck Interval Management (FIM, ED-195A / DO-328A);
  • Aircraft Surveillance Applications (ASA) System MOPS including several ADS-B In applications (ED-194A / DO-317A);
  • Flight-deck Interval Management (FIM) MOPS (ED-236 / DO-361).


  • Technical specifications for a Wide Area Multilateration (WAM) surveillance system (ED-142 with ED-142A due for publication in 2019).

These documents are available for purchase via the EUROCAE and RTCA websites.

Aircraft systems

The standardised ADS-B Out applications are dependent on several aircraft systems, including position source and transponder. The avionic requirements supporting the ADS-B 1090 MHz ES version 2 protocol are specified in Minimum Operational Performance Standards (MOPS) for 1090 MHz Extended Squitter ADS B (ED-102A / RTCA DO-260B, with corrigendum), which is the ADS-B Out baseline mandated in the Implementing Regulation published by the European Commission EU No 1207/2011 (and amendment). The Implementing Regulations can be accessed via our Surveillance library.

The avionic requirements for the standardised ADS-B In applications are specified in the Aircraft Surveillance Applications (ASA) System Minimum Operational Performance Standards (MOPS) (ED-194A / DO-317B) and Flight-deck Interval Management (FIM) MOPS (ED-236 / DO-361).

The first milestone in ADS-B Out airworthiness approval was achieved through the EASA AMC20-24, which was published in 2008. This Airworthiness approval supports the operations in, for example, Iceland, Australia and Canada. Additional implementations are expected to follow.

The airworthiness approval document detailing the surveillance avionics requirements, including ADS-B Out, compliant with the European Commission EU No 1207/2011 mandate is EASA CS-ACNS.

Ground systems

The Technical Specifications for the ADS-B Ground Station are published by EUROCAE (ED-129B).

The Technical Specification for the Wide Area Multilateration (WAM) system has been published by EUROCAE (ED-142). An update of this specification, published as ED-142A, is expected in the course of 2019. This will include “Composite ADS-B / WAM” provisions. The updates are currently being prepared by Sub-Group 4 of the EUROCAE Working Group 51.

Surveillance Modernisation Support team

Contact us for further information