| Abbreviation | Definition |
|---|---|
| R&R | Reproducibility And Repeatability |
| R&R | Resupply and Return |
| R&Z | Range and Zero |
| R/A | Radar Altimeter |
| R/C | Radio Command |
| R/C | Rate of Climb |
| R/C | Remote Control |
| R/D | Rate of Descent |
| R/E | Re-Entry |
| R/I | Receiving Inspection |
| R/L | Rate/Limited |
| R/L | Remote/Local |
| R/O | RollOut |
| R/S | Range Safety |
| R/S | Redundant Set |
| R/S | Reed Solomon |
| R/T | Real Time |
| R/T | Receiver/Transmitter |
| R/W | Read/Write |
| R/W | RunWay |