| Acronym | Meaning |
![](file.png) | HX | Heat Exchanger |
![](file.png) | HXIS | Hard X-ray Imaging Spectrometer |
![](file.png) | HYD | Hydraulic Subsystem |
![](file.png) | HYD | HYdraulics |
![](file.png) | HYDROGEN | Purge |
![](file.png) | HYDROGEN | ReHydrogen Relief |
![](file.png) | HYG | LHypergolic |
![](file.png) | HYPACE | Hybrid Programmable Attitude Control Electronics |
![](file.png) | HZ | Hertz (Cycles Per Second) |
![](file.png) | I | NTC/0INTC/0Integrated Checkout |
![](file.png) | I | LAS Instrument Landing Approach System |
![](file.png) | I | LSP IntegratedLogistics Support Plan |
![](file.png) | I | DAC Integrated Digital-Analog Converter |
![](file.png) | I | DAS Integrated Data Acquisition System |
![](file.png) | I | DPS Interface Digital Processor |
![](file.png) | I | ECM Induced Environment Contamination Monitor |
![](file.png) | I | ECO Inboard Engine Cutoff |
![](file.png) | I | LCCS Integrated Launch Control And Checkout System |
![](file.png) | I | D&CA Inverter Distribution And Control Assembly |
![](file.png) | I | FIntermediate Frequency |
![](file.png) | I-LOAD | Initial-load |
![](file.png) | I@@PL | Implement |
![](file.png) | IACS | Inertial Attitude Control System |
![](file.png) | IAD | Interface Agreement Document |
![](file.png) | IAD | Interface Analysis Document |
![](file.png) | IAL | Immediate Action Letter |
![](file.png) | IAL | International Algebraic Language |
![](file.png) | IARS | Independent Air Revitalization System |
![](file.png) | IAS | Impact Assessment Sheet |
![](file.png) | IAS | Indicated Airspeed |
![](file.png) | IAS | Integrated Avionics System |
![](file.png) | IASS | Inverter/ATCS Support Structure |
![](file.png) | IAT | Integrated Avionics Test |
![](file.png) | IAV | Inventory Adjustment Voucher |
![](file.png) | IB | Inboard |
![](file.png) | IB | Inert Building |
![](file.png) | IB | Instruction Book |
![](file.png) | IBF | Internally Blown Flap |
![](file.png) | IBM | International Business Machines |
![](file.png) | IC | Intercomputer Communication |
![](file.png) | IC/ES | Intercommunication/Emergency Station |
![](file.png) | ICA | Item Change Analysis |
![](file.png) | ICAO | International Civil Aviation Organization |
![](file.png) | ICAO | International Civil Aviation Organization |
![](file.png) | ICAR | Investigation And Corrective Action Report |
![](file.png) | ICB | Interim Change Bulletin |
![](file.png) | ICB | Interrupt Control Block |
![](file.png) | ICC | Intercomputer Channel |
![](file.png) | ICC | Intercomputer Communication |
![](file.png) | ICC | Interface Control Chart |