| Acronym | Meaning |
| IDCU | Ice Detector Control Unit |
| IDD | Interface Design Document |
| IDE | Interactive Development Environments |
| IDR | Installation Design Review |
| IDS | Interface Design Specification Udi-e-21403/mod |
| IECM | Inflight Engine Conditioning Monitoring |
| IECMS | In Flight Engine Condition Monitoring System |
| IECS | Intergrated Environmental Control System |
| IEEE | Institute Of Electrical And Electronic Engineers |
| IF | Intermediate Frequency |
| IFB | Invitation For Bids |
| IFF | Identification Friend Or Foe |
| IFM | Improved Fm |
| IFPM | In Flight Performance Monitoring |
| IFR | Instrument Flight Rules |
| IG | Image Generator |
| IG | Inspector General |
| IGDS | Image Generation & Display System |
| IGE | In Ground Effect |
| IGES | Initial Graphics Exchange Specification |
| IGNRQ | Ignition Request |
| IHADSS | Integrated Helmet And Display Sighting System |
| IHU | Integrated Helmet Unit |
| ILS | Instrument Landing System |
| ILS | Integrated Logistics Support |
| ILS/SE | Integrated Logistic Support/systems Engineering |
| ILSDS | Integrated Logistic Support Evaluation & Supportability Assur |
| ILSM | Integrated Logistics Support Manager |
| ILSMT | Integrated Logistic Support Management Team |
| ILSP | Integrated Logistics Support Plan |
| IM | Information Management |
| IM | Information Model |
| IMA | Intermediate Maintenance Activity |
| IMC | Instrument Meteorological Conditions |
| IMCON | Information Modeling Convergence |
| IMCT | Intermodule Compatibility Testing |
| IMD | Intregrated Map Display |
| IMRR | Inspection Maintenance And Repair Record |
| IMTC | Intermodal Compatibility |
| IN | Nacelle Angle |
| INAV | Inertial Navigation |
| INBD | Inboard |
| INC | Increase |
| INCOMPLT | Incomplete |
| INCOR | Incorrect |
| IND | Indicator |
| INIT | Initiatetmtinitialize |
| INRGL | Ignition Request Left Engine |
| INS | Inertial Navigation System |
| INST | Instrument |