| h |
hour |
| H2 |
Hydrogen |
| H2O2 |
Hydrogen Peroxide |
| HA |
Hour Angle |
| HALEU |
High Assay Low Enriched Uranium |
| HAPS |
High Altitude Platform Station |
| HAT |
Height Above Terrain |
| HCE |
Heater Control Electronics |
| HCI |
Host Computer Interface |
| HCU |
Hyper Combine Unit |
| HDLC |
High speed Data Link Control |
| HDRM |
Hold Down and Release Mechanism |
| HDTV |
High Definition Television |
| HDX |
Half Duplex |
| HE |
Heat Exchanger |
| He |
Helium |
| HEAO |
High Energy Astronomy Observatory |
| HEEO |
Highly Elliptical Earth Orbit |
| HEMO |
Highly Elliptical Mars Orbit |
| HEMT |
High Electron Mobility Transistor |
| HEO |
High Earth Orbit |
| HEO |
Highly Elliptical Orbit |
| HEOS |
Highly Eccentric Orbit Satellite |
| HF |
High Frequency |
| HF |
Human Factors |
| HGA |
High Gain Antenna |
| HIF |
Horizontal Integration Facility |
| HL |
High Load |
| HLES |
Home Land Earth Station |
| HLLV |
Heavy Lift Launch Vehicle |
| HLR |
Home Location Register |
| HLS |
Human Landing System |
| HLV |
Heavy Lift Launch Vehicle |
| HM |
Hybrid Modulation |
| HNMC |
Hub Network Management Computer |
| HP |
Horsepower |
| HPA |
High Power Amplifier |
| HPC |
High Power Converter |
| HPF |
High Pass Filter |
| HPFTP |
High Pressure Fuel Turbopump |
| HPOTP |
High Pressure Oxidiser Turbopump |
| HPM |
Hybrid Phase Modulation |
| HPP |
Host Protocol Processor |
| HPTP |
High Pressure Turbopump |
| HPU |
Hydraulic Power Unit |
| HRC |
Hypothetical Reference Circuit |
| HRDP |
Hypothetical Reference Digital Path |
| HRX |
Hypothetical Reference Connection |
| HSC |
Hangover Control and Signal Classification |
| HSD |
High Speed Data |
| HSI |
HyperSpectral Imager |
| HSIU |
High Speed Interface Unit |
| HSP |
Host Satellite Processor |
| HTF |
Hub Terminal Facility |
| HTHL |
Horizontal Takeoff Horizontal Landing |
| HTML |
Hypertext Mark-up Language |
| HTS |
High Throughput Satellite |
| HTS |
Horizontal Test Stand |
| HTTP |
Hypertext Transfer Protocol |
| HTVL |
Horizontal Takeoff Vertical Landing |
| HU |
High Usage Circuit |
| HUD |
Heads Up Display |
| HVCS |
Half Voice Circuits |
| H/W |
Hardware |
| HWCI |
Hardware Configuration Item |
| HWIL |
Hardware In The Loop |
| HYPACE |
Hybrid Programmable Attitude Control Electronics |
| Hz |
Hertz - cycles per second |
