---
title: "CS ADR-DSN.S.885 System design — Certification Specifications and Guidance Material for Aerodrome Design (CS-ADR-DSN) — Issue 7, Aerodromes · Avioverse"
description: "For a runway meant for use in runway visual range conditions less than a value of 550 m, the electrical systems for the power supply, lighting, and…"
url: "https://avioverse.aero/regulations/easa/aerodromes/cs-adr-dsn/chapter-s-electrical-systems/cs-adr-dsn-s-885"
---

# CS ADR-DSN.S.885 System design

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

IR Implementing rule

## CS ADR-DSN.S.885 System design

(a) For a [runway](https://avioverse.aero/glossary/easa/runway) meant for use in runway visual range conditions less than a value of 550 m, the electrical systems for the power supply, lighting, and control of the lighting systems included in Table S-1 should be so designed that an equipment failure should not leave the pilot with inadequate visual guidance or misleading information.

(b) Where the secondary power supply of an [aerodrome](https://avioverse.aero/glossary/easa/aerodrome) is provided by the use of duplicate feeders, such supplies should be physically and electrically separate so as to ensure the required level of availability and independence.

(c) Where a runway forming part of a standard taxi-route is provided with runway lighting and [taxiway](https://avioverse.aero/glossary/easa/taxiway) lighting, the lighting systems should be interlocked to preclude the possibility of simultaneous operation of both forms of lighting.

IR · CS ADR-DSN.S.885 — Regulation (EU) No 139/2014 · ED Decision 2014/013/R · Aerodromes Easy Access Rules · EAR revision 13 Mar 2026

[All rules in CHAPTER S — ELECTRICAL SYSTEMS](https://avioverse.aero/regulations/easa/aerodromes/cs-adr-dsn/chapter-s-electrical-systems)

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.