| NB: The definitions below are for words, or technical vocabulary, specific to Military Air Environment use. |
| Where a word appears in the Oxford English Dictionary (OED), the definition below is specific only to the |
| associated context and OED definitions should be used in all other usages. |
| Term | Abbreviation | Chapter Reference |
| Design Modification | DM | Chap 10.3 |
| Description |
| A modification that provides a permanent change to the build standard of materiel. Changes are incorporated into |
| technical publications and the modification is fully supported with spares and special tools, etc. |