---
title: "Appendix B to point 21L.A.103 Classification of changes to the design of an aircraft for which design compliance has been declared — Annex Ib, Initial Airworthiness · Avioverse"
description: "The following tables provide examples of ‘substantial’ changes."
url: "https://avioverse.aero/regulations/easa/initial-airworthiness/annex-ib/section-a-technical-requirements/appendix-b"
---

# Appendix B to point 21L.A.103 Classification of changes to the design of an aircraft for which design compliance has been declared

Annex Ib · Regulation (EU) No 748/2012 · EAR revision 27 Nov 2025

Appendix Appendix

## Appendix B to point 21L.A.103 Classification of changes to the design of an aircraft for which design compliance has been declared

The following tables provide examples of ‘substantial’ changes. The classification may change due to cumulative effects and/or combinations of individual changes.

A.1 Examples of ‘substantial’ changes for small aeroplanes (CS-23)

A.1.1 Table A-1 contains examples of changes that are ‘substantial’ for small aeroplanes (CS-23).

Table A-1 — Examples of when a new declaration of design compliance would be required under Subpart C for substantial changes for small aeroplanes (CS-23)

| Example | Description of change                                        | Notes                                                                                                                                                                      |
| ------- | ------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| 1.      | Change to wing location (tandem, forward, canard, high/low). | Proposed change to the design is so extensive that a substantially complete demonstration of compliance with the applicable detailed technical specifications is required. |
| 2.      | Change to engine configuration (tractor/pusher).             | Proposed change to the design is so extensive that a substantially complete demonstration of compliance with the applicable detailed technical specifications is required. |
| 3.      | Change from an all-metal to all-composite aeroplane.         | Proposed change to the design is so extensive that a substantially complete demonstration of compliance with the applicable detailed technical specifications is required. |

APPENDIX · Appendix B — Regulation (EU) No 748/2012 · ED Decision 2023/013/R · Initial Airworthiness Easy Access Rules · EAR revision 27 Nov 2025

[All rules in SECTION A - TECHNICAL REQUIREMENTS](https://avioverse.aero/regulations/easa/initial-airworthiness/annex-ib/section-a-technical-requirements)

Consolidated from the EASA Easy Access Rules (revision 27 Nov 2025, 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.