---
title: "CS 25.705 Runway overrun awareness and alerting systems — CS-25 · Avioverse"
description: "(See AMC 25.705) A runway overrun awareness and alerting system (ROAAS) must be installed."
url: "https://avioverse.aero/regulations/easa/cs-25/subpart-d/cs-25-705"
---

# CS 25.705 Runway overrun awareness and alerting systems

Large Aeroplanes (CS-25) · CS-25 · EAR revision 26 Jan 2023

IR Implementing rule

## CS 25.705 Runway overrun awareness and alerting systems

(See AMC 25.705)

A runway overrun awareness and alerting system (ROAAS) must be installed. The ROAAS shall reduce the risk of a longitudinal runway excursion during landing by providing alert, in flight and on ground, to the flight crew when the aeroplane is at risk of not being able to stop within the available distance to the end of the runway.

(a) During approach (from a given height above the selected runway) and landing, the ROAAS shall perform real-time energy-based calculations of the predicted landing stopping point, compare that point with the location of the end of the runway, and provide the flight crew with:

(1) in-flight, timely, and unambiguous predictive alert(s) of a runway overrun risk, and

(2) on-ground, timely, and unambiguous predictive alert(s) of a runway overrun risk. At the option of the applicant, the ROAAS may also provide an automated means of deceleration control that prevents or minimises runway overrun during landing.

(b) The ROAAS shall at least accommodate dry and wet runway conditions for normal landing configurations.

\[Amdt 25/24]

IR · CS 25.705 — CS-25 · ED Decision 2020/001/R · CS-25 Easy Access Rules · EAR revision 26 Jan 2023

AMC Acceptable means of compliance

## AMC 25.705 Runway overrun awareness and alerting systems

1\. When demonstrating compliance with CS 25.705, the applicant should take account of EUROCAE Document ED-250, ‘Minimum Operational Performance Standard for a Runway Overrun Awareness and Alerting System’, dated December 2017.

2\. When demonstrating compliance with CS 25.1581 and CS 25.1585, the applicant should include in the aeroplane flight manual the following elements:

(1) A description of the runway overrun awareness and alerting system (ROAAS) operational domain, including all conditions for which the ROAAS is expected to perform its intended function,

(2) Any operational limitations applicable to the ROAAS, and

(3) Operational procedures to be used by the flight crew when ROAAS alerts are triggered.

\[Amdt 25/24]

AMC · AMC 25.705 — CS-25 · ED Decision 2020/001/R · CS-25 Easy Access Rules · EAR revision 26 Jan 2023

[All rules in SUBPART D – DESIGN AND CONSTRUCTION](https://avioverse.aero/regulations/easa/cs-25/subpart-d)

Consolidated from the EASA Easy Access Rules (revision 26 Jan 2023, 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.