| Acronym | Meaning |
| SPA | Steering Position Amplifier |
| PASS | Planning And Scheduling System |
| CICU | Computer Interface Conditioning Unit |
| ECS | Environmental Control System (Subsystem) |
| M | Male |
| OP | Oxygen Purge |
| N | Neutrons |
| D | Drag |
| IPS | Ips International Pipe Standard |
| DDM | Data Display Monitoring |