| 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 |
| Service Modification | SM | Chap 10.4 |
| Description |
| A modification to an aircraft or equipment designed, developed, produced and embodied by, or for, the Service. |
| The IPT retains responsibility for the modification until such time as it is superseded by a cover modification. |