| Abbreviation | Definition |
|---|---|
| FIG | FIGure |
| FIIG | Federal Item Identification Guide |
| FIL | FILament |
| FILE | Future Identification and Location Experiment |
| FIM | Facing Identification Marking |
| FIO | Furnished and Installed by Others |
| FIR | Fuel Indicating Reading |
| FIRAS | Far InfraRed Absolute Spectrophotometer |
| FIRST | Far-InfraRed Space Telescope |
| FIS | Facility Interface Sheet |
| FIT | Fault Isolation Test |
| FITH | Fire-In-The-Hole |
| FITS | FAA Industry Training Standard |
| FITS | Flexible Image Transport System |
| FIV | Fuel Isolation Valve |
| FKB | Flight Display Keyboard |
| FKF | Flight Kits Facility |
| FL | Fail |
| FL | Feed Line |
| FL | Flow Line |