---
title: "GM1 141. ATS surveillance system — ANNEX I — Part-DEFINITIONS, ATM/ANS · Avioverse"
description: "GENERAL A comparable ground-based system is one that has been demonstrated, by comparative assessment or other methodology, to have a level of safety and…"
url: "https://avioverse.aero/regulations/easa/atm-ans/part-definitions/general/gm1-141-ats-surveillance-system"
---

# GM1 141. ATS surveillance system

ANNEX I — Part-DEFINITIONS · Regulation (EU) 2017/373 · EAR revision 12 Mar 2025

Official sources: [EASA Easy Access Rules (opens in a new tab)](https://www.easa.europa.eu/en/document-library/easy-access-rules/easy-access-rules-air-traffic-managementair-navigation-services-provision-services) · [EUR-Lex 2017/373 (opens in a new tab)](https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32017R0373)

GM Guidance material

## GM1 141. ATS surveillance system

GENERAL

A comparable ground-based system is one that has been demonstrated, by comparative assessment or other methodology, to have a level of safety and performance equal to or better than monopulse SSR.

GM — Regulation (EU) 2017/373 · ED Decision 2020/008/R · ATM/ANS Easy Access Rules · EAR revision 12 Mar 2025

[All rules in General provisions](https://avioverse.aero/regulations/easa/atm-ans/part-definitions/general)

Consolidated from the EASA Easy Access Rules (revision 12 Mar 2025, extracted 2 Nov 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.