---
title: "CS 25.969 Fuel tank expansion space — CS-25 · Avioverse"
description: "Each fuel tank must have an expansion space of not less than 2% of the tank capacity."
url: "https://avioverse.aero/regulations/easa/cs-25/subpart-e/cs-25-969"
---

# CS 25.969 Fuel tank expansion space

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

IR Implementing rule

## CS 25.969 Fuel tank expansion space

Each fuel tank must have an expansion space of not less than 2% of the tank capacity. It must be impossible to fill the expansion space inadvertently with the aeroplane in the normal ground attitude. For pressure fuelling systems, compliance with this paragraph may be shown with the means provided to comply with CS 25.979(b).

IR · CS 25.969 — CS-25 · ED Decision 2003/2/RM · CS-25 Easy Access Rules · EAR revision 26 Jan 2023

[All rules in SUBPART E – POWERPLANT](https://avioverse.aero/regulations/easa/cs-25/subpart-e)

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.