---
title: "GM1 ADR-DSN.M.635 Precision approach Category II and III lighting system — Certification Specifications and Guidance Material for Aerodrome Design (CS-ADR-DSN) — Issue 7, Aerodromes · Avioverse"
description: "The length of 900 m is based on providing guidance for operations under Category I, II and III conditions."
url: "https://avioverse.aero/regulations/easa/aerodromes/cs-adr-dsn/chapter-m-visual-aids-for-navigation-lights/gm1-adr-dsn-m-635"
---

# GM1 ADR-DSN.M.635 Precision approach Category II and III lighting system

Certification Specifications and Guidance Material for Aerodrome Design (CS-ADR-DSN) — Issue 7 · Regulation (EU) No 139/2014 · EAR revision 13 Mar 2026

GM Guidance material

## GM1 ADR-DSN.M.635 Precision approach Category II and III lighting system

The length of 900 m is based on providing guidance for operations under Category I, II and III conditions. Reduced lengths may support Category II and III operations but may impose limitations on Category I operations. Additional guidance is given in ICAO Annex 14, Attachment A, Section 11.

\[Issue: ADR-DSN/3]

GM · GM1 ADR-DSN.M.635 — Regulation (EU) No 139/2014 · ED Decision 2016/027/R · Aerodromes Easy Access Rules · EAR revision 13 Mar 2026

[All rules in CHAPTER M — VISUAL AIDS FOR NAVIGATION (LIGHTS)](https://avioverse.aero/regulations/easa/aerodromes/cs-adr-dsn/chapter-m-visual-aids-for-navigation-lights)

Consolidated from the EASA Easy Access Rules (revision 13 Mar 2026, 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.