---
title: "MODULE 6. MATERIALS AND HARDWARE — Part-66 · Avioverse"
description: "MODULE 6. MATERIALS AND HARDWARE LEVEL A B1 B3 B2 B2L 6.1 Aircraft materials — ferrous (a) Alloy steels used in aircraft;"
url: "https://avioverse.aero/regulations/easa/continuing-airworthiness/part-66/appendices-to-annex-iii-part-66/module-6-materials-and-hardware"
---

# MODULE 6. MATERIALS AND HARDWARE

Annex III (Part-66) · Regulation (EU) No 1321/2014 · EAR revision 2 Sep 2025

IR Implementing rule

## MODULE 6. MATERIALS AND HARDWARE

| MODULE 6. MATERIALS AND HARDWARE                                                  |                                       |                                        | LEVEL |       |        |
| --------------------------------------------------------------------------------- | ------------------------------------- | -------------------------------------- | ----- | ----- | ------ |
|                                                                                   |                                       |                                        | A     | B1 B3 | B2 B2L |
| 6.1 [Aircraft](https://avioverse.aero/glossary/easa/aircraft) materials — ferrous |                                       |                                        |       |       |        |
|                                                                                   | (a) Alloy steels used in aircraft;    |                                        | 1     | 2     | 1      |
|                                                                                   | (b) Testing of ferrous materials;     |                                        | —     | 1     | 1      |
|                                                                                   | (c) Repair and inspection procedures. |                                        | —     | 2     | 1      |
| 6.2 Aircraft materials — non-ferrous                                              |                                       |                                        |       |       |        |
|                                                                                   | (a) Characteristics;                  |                                        | 1     | 2     | 1      |
|                                                                                   | (b) Testing of non-ferrous materials; |                                        | —     | 1     | 1      |
|                                                                                   | (c) Repair and inspection procedures. |                                        | —     | 2     | 1      |
| 6.3 Aircraft materials – composite and non-metallic                               |                                       |                                        |       |       |        |
| 6.3.1 Composite and non-metallic other than wood and fabric                       |                                       |                                        |       |       |        |
|                                                                                   |                                       | (a) Characteristics;                   | 1     | 2     | 2      |
|                                                                                   |                                       | (b) Detection of defects               | 1     | 2     | —      |
|                                                                                   |                                       | (c) Repairs and inspection procedures. | —     | 2     | 1      |
| 6.3.2 Wooden structures                                                           |                                       |                                        | 1     | 1     | —      |
| 6.3.3 Fabric covering                                                             |                                       |                                        | —     | 1     | —      |
| 6.4 Corrosion                                                                     |                                       |                                        |       |       |        |
|                                                                                   | (a) Chemical fundamentals;            |                                        | 1     | 1     | 1      |
|                                                                                   | (b) Types of corrosion.               |                                        | 2     | 3     | 2      |
| 6.5 Fasteners                                                                     |                                       |                                        |       |       |        |
| 6.5.1 Screw threads                                                               |                                       |                                        | 2     | 2     | 2      |
| 6.5.2 Bolts, studs and screws                                                     |                                       |                                        | 2     | 2     | 2      |
| 6.5.3 Locking devices                                                             |                                       |                                        | 2     | 2     | 2      |
| 6.5.4 Aircraft rivets                                                             |                                       |                                        | 1     | 2     | 1      |
| 6.6 Pipes and unions                                                              |                                       |                                        |       |       |        |
|                                                                                   | (a) Identification;                   |                                        | 2     | 2     | 2      |
|                                                                                   | (b) Standard unions.                  |                                        | 2     | 2     | 1      |
| 6.7 Springs                                                                       |                                       |                                        | —     | 2     | 1      |
| 6.8 Bearings                                                                      |                                       |                                        | 1     | 2     | 2      |
| 6.9 Transmissions                                                                 |                                       |                                        | 1     | 2     | 2      |
| 6.10 Control cables                                                               |                                       |                                        | 1     | 2     | 1      |
| 6.11 Electrical cables and connectors                                             |                                       |                                        | 1     | 2     | 2      |

IR — Regulation (EU) No 1321/2014 · Regulation (EU) 2023/989 · Continuing Airworthiness Easy Access Rules · EAR revision 2 Sep 2025

[All rules in APPENDICES TO ANNEX III (Part-66)](https://avioverse.aero/regulations/easa/continuing-airworthiness/part-66/appendices-to-annex-iii-part-66)

Consolidated from the EASA Easy Access Rules (revision 2 Sep 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.