---
title: "CS 25.631 Bird strike damage — CS-25 · Avioverse"
description: "(See AMC 25.631) The aeroplane must be designed to assure capability of continued safe flight and landing of the aeroplane after impact with a 4 lb bird…"
url: "https://avioverse.aero/regulations/easa/cs-25/subpart-d/cs-25-631"
---

# CS 25.631 Bird strike damage

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

IR Implementing rule

## CS 25.631 Bird strike damage

(See AMC 25.631)

The aeroplane must be designed to assure capability of continued safe flight and landing of the aeroplane after impact with a 4 lb bird when the velocity of the aeroplane (relative to the bird along the aeroplane’s flight path) is equal to VC at sealevel or 0·85 VC at 2438 m (8000 ft), whichever is the more critical. Compliance may be shown by analysis only when based on tests carried out on sufficiently representative structures of similar design.

\[Amdt 25/18]

IR · CS 25.631 — CS-25 · ED Decision 2016/010/R · CS-25 Easy Access Rules · EAR revision 26 Jan 2023

AMC Acceptable means of compliance

## AMC 25.631 Bird strike damage

Consideration should be given in the early stages of the design to the installation of items in essential services, such as control system components, and items which, if damaged, could cause a hazard, such as electrical equipment. As far as practicable, such items should not be installed immediately behind areas liable to be struck by birds.

AMC · AMC 25.631 — CS-25 · ED Decision 2003/2/RM · 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.