---
title: "GM No 2 to 21.A.121 Applicability – Applicable design data — Annex I, Initial Airworthiness · Avioverse"
description: "Applicable design data is defined as all the necessary drawings, specifications and other technical information provided by the applicant for, or holder…"
url: "https://avioverse.aero/regulations/easa/initial-airworthiness/annex-i/section-a-technical-requirements/gm-no-2-to-21-a-121-applicability-applicable-design-data"
---

# GM No 2 to 21.A.121 Applicability – Applicable design data

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

Official sources: [EASA Easy Access Rules (opens in a new tab)](https://www.easa.europa.eu/en/document-library/easy-access-rules/easy-access-rules-initial-airworthiness-and-environmental) · [EUR-Lex 2012/748 (opens in a new tab)](https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32012R0748)

GM Guidance material

## GM No 2 to 21.A.121 Applicability – Applicable design data

Applicable design data is defined as all the necessary drawings, specifications and other technical information provided by the applicant for, or holder of a design organisation approval, TC, STC, approval of repair or minor change design, or [ETSO](https://avioverse.aero/glossary/easa/etso) authorisation (or equivalent when [Part 21](https://avioverse.aero/glossary/easa/part-21) Section A Subpart F is used for production of products, parts or appliances, the design of which has been approved other than according to Part 21), and released in a controlled manner to the manufacturer that produces under Part 21 Subpart F. This should be sufficient for the development of production data to enable manufacture in conformity with the design data.

Prior to the issue of the TC, STC, approval of repair or minor change design or ETSO authorisation, or equivalent, design data is defined as ‘not approved’, but parts and appliances may be released with an EASA Form 1 as a certificate of conformity.

After the issue of the TC, STC, approval of repair or minor change or ETSO authorisation, or equivalent, this design data is defined as ‘approved’ and items manufactured in conformity are eligible for release on an EASA Form 1 for airworthiness purposes.

For the purpose of Subpart F of Part 21, the term ‘applicable design data’ includes the information related to the applicable engine exhaust emissions and aeroplane CO2 emissions production cut-off requirements.

GM — Regulation (EU) No 748/2012 · ED Decision 2019/018/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-i/section-a-technical-requirements)

Consolidated from the EASA Easy Access Rules (revision 27 Nov 2025, extracted 2 Nov 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.