| Acronym | Meaning |
| M | Mega |
| PDP | Preliminary Definition Plan |
| MSI | Maintenance Significant Items |
| GPME | General Purpose Mission Equipment |
| MRD | Mission Requirements Document |
| DECS | Civil Engineering Office At Vandenberg |
| SLS | Secondary Landing Site |
| L/S | Landing Site |
| PIECP | Preliminary Impact Engineering Change Proposal |
| NCI | Phasing Maneuver |