---
title: "CS 25.373 Speed control devices — CS-25 · Avioverse"
description: "If speed control devices (such as spoilers and drag flaps) are installed for use in en-route conditions:"
url: "https://avioverse.aero/regulations/easa/cs-25/subpart-c/cs-25-373"
---

# CS 25.373 Speed control devices

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

IR Implementing rule

## CS 25.373 Speed control devices

If speed control devices (such as spoilers and drag flaps) are installed for use in en-route conditions:

(a) The aeroplane must be designed for the symmetrical manoeuvres and gusts prescribed in CS 25.333, CS 25.337, the yawing manoeuvres in CS 25.351, and the vertical and lateral gust and turbulence conditions prescribed in CS 25.341(a) and (b) at each setting and the maximum speed associated with that setting; and

(b) If the device has automatic operating or load limiting features, the aeroplane must be designed for the manoeuvre and gust conditions prescribed in sub-paragraph (a) of this paragraph, at the speeds and corresponding device positions that the mechanism allows.

\[Amdt 25/1]

IR · CS 25.373 — CS-25 · ED Decision 2005/006/R · CS-25 Easy Access Rules · EAR revision 26 Jan 2023

[All rules in SUBPART C – STRUCTURE](https://avioverse.aero/regulations/easa/cs-25/subpart-c)

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.