---
title: "21.A.173 Classification — Annex I, Initial Airworthiness · Avioverse"
description: "Airworthiness certificates shall be classified as follows: certificates of airworthiness shall be issued to aircraft which conform to a type-certificate…"
url: "https://avioverse.aero/regulations/easa/initial-airworthiness/annex-i/section-a-technical-requirements/21-a-173"
---

# 21.A.173 Classification

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

IR Implementing rule

## 21.A.173 Classification

Airworthiness certificates shall be classified as follows:

(a) certificates of airworthiness shall be issued to aircraft which conform to a type-certificate that has been issued in accordance with this Annex I ([Part 21](https://avioverse.aero/glossary/easa/part-21));

(b) restricted certificates of airworthiness shall be issued to aircraft:

1\. which conform to a restricted type-certificate that has been issued in accordance with this Annex I (Part 21); or

2\. which have been shown to the Agency to comply with specific airworthiness specifications ensuring adequate safety.

IR · 21.A.173 — Regulation (EU) No 748/2012 · 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 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.