| Acronym | Meaning |
| OF | Oxygen Fill |
| UPS | Uninterruptible Power System |
| SPS | Service Propulsion Subsystem |
| OPR | Orbiter/Payload Recorder |
| LH2 | Liquid Hydrogen |
| LCU | Inertial Components Temperature Controller |
| FLTSATCOM | Fleet Satellite Communications |
| MSI | Maintenance Significant Items |
| HQ | Headquarters (HDQ Preferred) |
| OVI | Operational Validation Inspection |