| Acronym | Meaning |
| NRL | Naval Research Laboratory |
| SEI | SuPPort EquiPment Installation |
| OGS | Outer Glideslope |
| CCS | Command And Control Subsystem |
| OESS | Orbiter/ET Separation Subsystem |
| POGO | Polar Orbiting GeophYsical Observatory |
| L-P | Low Pressure |
| TECH | Technical |
| SPLX | Simplex |
| SID | System Interface Document |