| Abbreviation | Definition |
|---|---|
| IPDR | Incremental Preliminary Design Review |
| IPE | Industrial Plant Equipment |
| IPF | IUS (Inertial Upper Stage) Processing Facility |
| IPIE | Institute for Precision Instrument Engineering |
| IPL | Indentured Parts List |
| IPR | Interim Problem Report |
| IPS | Inches Per Second |
| IPS | Instrument Pointing System |
| IPS | Instrumentation Power Subsystem |
| IPS | Interface Problem Sheets |
| IPS | International Pipe Standard |
| IPS | Inverter Power Supply |
| IPSL | Interface Problem Status Log |
| IPT | In-Plant Transporter |
| IPT | International Pipe Thread |
| IPTCS | Igloo Passive Thermal Control Section |
| IR | Inclination of the Ascending Return |
| IR | Inside Radius |
| IR | International Rendezvous |
| IRANSAT | Iranian Government Communications Satellite (replaces IRAN) |