---
title: "AIS.TR.350 Terrain and obstacle data – General requirements — SPECIFIC REQUIREMENTS FOR THE PROVIDERS OF AERONAUTICAL INFORMATION SERVICES, ATM/ANS · Avioverse"
description: "The coverage areas for sets of terrain and obstacle data shall be specified as:"
url: "https://avioverse.aero/regulations/easa/atm-ans/specific-requirements-for-the-providers-of/subpart-b/ais-tr-350"
---

# AIS.TR.350 Terrain and obstacle data – General requirements

SPECIFIC REQUIREMENTS FOR THE PROVIDERS OF AERONAUTICAL INFORMATION SERVICES · Regulation (EU) 2017/373 · EAR revision 12 Mar 2025

IR Implementing rule

## AIS.TR.350 Terrain and obstacle data – General requirements

The coverage areas for sets of terrain and obstacle data shall be specified as:

(a) Area 1: the entire territory of a Member State;

(b) Area 2: within the vicinity of an aerodrome, subdivided as follows:

(1) Area 2a: a rectangular area around a runway which comprises the runway strip plus any clearway that exists;

(2) Area 2b: an area extending from the ends of Area 2a in the direction of departure, with a length of 10 km and a splay of 15 % to each side;

(3) Area 2c: an area extending outside Areas 2a and 2b at a distance of not more than 10 km from the boundary of Area 2a; and

(4) Area 2d: an area outside Areas 2a, 2b and 2c up to a distance of 45 km from the aerodrome reference point, or to an existing terminal manoeuvring area (TMA) boundary, whichever is nearer;

(c) Area 3: the area bordering an aerodrome movement area which extends horizontally from the edge of a runway to 90 m from the runway centre line and 50 m from the edge of all other parts of the aerodrome movement area; and

(d) Area 4: the area extending 900 m prior to the runway threshold and 60 m to each side of the extended runway centre line in the direction of the approach on a precision approach runway, Category II or III.

IR · AIS.TR.350 — Regulation (EU) 2017/373 · Commission Implementing Regulation (EU) 2020/469 · ATM/ANS Easy Access Rules · EAR revision 12 Mar 2025

GM Guidance material

## GM1 AIS.TR.350(d) Terrain and obstacle data — General requirements

AREA 4

Where the terrain at a distance greater than 900 m (3 000 ft) from the runway threshold is mountainous or otherwise significant, the length of Area 4 should be extended to a distance not exceeding 2 000 m (6 500 ft) from the runway threshold.

GM · GM1 AIS.TR.350(d) — Regulation (EU) 2017/373 · ED Decision 2020/008/R · ATM/ANS Easy Access Rules · EAR revision 12 Mar 2025

[All rules in SUBPART B — TECHNICAL REQUIREMENTS FOR PROVIDERS OF AERONAUTICAL INFORMATION SERVICES (AIS.TR)](https://avioverse.aero/regulations/easa/atm-ans/specific-requirements-for-the-providers-of/subpart-b)

Consolidated from the EASA Easy Access Rules (revision 12 Mar 2025, extracted 13 Oct 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.