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Acronyms, we have a few.


Photo: Alphabet soup

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AC - Alternating Current

ACC - Air Conditioning Controller

ACP - Audio Control Panel, Air Conditioning Pack

ADS - Air Data System

ADS-B - Automatic Dependent Surveillance-Broadcast

ADS-C - Automatic Dependent Surveillance-Contract

AGM - Advanced Graphics Module

AHRS - Attitude Heading Reference System

AHTMS - Aircraft Health & Trend Monitoring System

AOC - Aeronautical Operational Communication

AOM - Aircraft Operating Manual

APM - Aircraft Personality Module

APU - Auxiliary Power Unit

ASC - Aircraft Service Change

ASCB - Avionics Standard Communication Bus

ATCAT - Advanced Technology Customer Advisory Team

ATS - Air Traffic Services, Air Turbine Starter

AUX - Auxiliary


BAC - Bleed Air Controller

BAPI - Brake Accumulator Pressure Indicator

BCS - Brake Control System

BCU - Brake Control Unit

BFCU - Backup Flight Control Unit

BITE - Built In Test Equipment

BPCU - Bus Power Control Unit

BPT - Break Power Transfer

BTMS - Brake Temperature Monitoring System

BWI - Bearing Wear Indicator


CA - Consequential Alert

CAS - Crew Alerting System

CAU - Crew Audio Unit

CCD - Cursor Control Device

CFIT - Controlled Flight Into Terrain

CLAWS - Control Laws

CMC - Central Maintenance Computer

CMF - Communication Management Function

CMS - Configuration Management System

COP - Cockpit Overhead Panel

CPAM - Cabin Pressure Acquisition Module

CPCP - Cabin Pressure Control Panel

CPCS - Cabin Pressure Control System

CPDLC - Controller Pilot Datalink Communication

CPI - Cabin Pressure Indicator

POP - Copilot Overhead Panel

CSD - Constant Speed Drive


DC - Direct Current

DCN - Data Concentration Network

DU - Display Unit

DS - Display Screen


E-Batts - Emergency Batteries

EBHA - Electric Backup Hydraulic Actuator

ECM - Electronic Control Module

ECS - Environmental Control System

ECU - Electronic Control Unit

EDM - Emergency Descent Mode

EEC - Electronic Engine Controller

EED - Emergency Exit Door

EGPWS - Enhanced Ground Proximity Warning System

EGT - Exhaust Gas Temperature

EICAS - Engine Instruments and Crew Alerting System

EIS - Entry Into Service

EPCP - Electrical Power Control Panel

EPR - Engine Pressure Ratio

EPU - Estimated Position of Uncertainty

ESS - Essential

EVAS - Emergency Vision Assurance System

EVM - Engine Vibration Monitor

EVMS - Engine Vibration Monitoring System

EVS - Enhanced Vision System


FADEC - Full Authority Digital Engine Control

FBW - Fly-By-Wire

FCC - Flight Control Computer

FCOC - Fuel Cooled Oil Cooler

FCS - Flight Control System

FCU - Flush Control Unit

FDCU - Fire Detection Control Unit

FECU - Flap Electronic Control Unit

FGC - Flight Guidance Computer

FLIR - Forward Looking Infrared

FMU - Fuel Metering Unit

FMS - Flight Management System

FPA - Flight Path Angle

FPM - Flight Path Marker

FPV - Flight Path Vector

FQSC - Fuel Quantity Signal Conditioner

FWC - Fault Warning Computer


GCMS - Gulfstream Cabin Management System

GCU - Generator Control Unit

GP - Guidance Panel

GSB - Ground Service Bus

GSCP - Ground Service Control Panel


HCM - Hydraulic Control Module

HFRS - Heated Fuel Return System

HP - High Pressure

HPSOV - High Pressure Shutoff Valve

HSCU - Horizontal Stabilizer Control Unit

HSTA - Horizontal Stabilizer Trim Actuator

HSTS - Horizontal Stabilizer Trim System


IDG - Integrated Drive Generator

IDGSACOC - IDG Surface Air Cooled Oil Cooler

IRS - Inertial Reference System

IRU - Inertial Reference Unit


kVA - Kilovolt-ampere


LCD - Liquid Crystal Display

LED - Light Emitting Diode

LEER - Left Electronic Equipment Rack

LGCU - Landing Gear Control Unit

LP - Low Pressure

LRU - Line Replaceable Unit


MAU - Modular Avionics Unit

MCDU - Multifunction Control Display Unit

MCE - Motor Control Electronics

MCT - Maximum Continuous Thrust

MED - Main Entry Door

MFD - Multifunction Display

MLG - Main Landing Gear

MMCU-Manual Motor Control Unit

MPT - Modular Power Tile

MRC - Modular Radio Cabinet

MWF - Monitor Warning Function


NBPT - No Break Power Transfer

NLG - Nose Landing Gear

NUC - Non-Uniformity Correction

NWS - Nose Wheel Steering


OHPTS - Overhead Panel Touchscreen


PBE - Protective Breathing Equipment

PBSSS - Performance Based Sensor Selection Scheme

PDB - Power Distribution Box

PDU - Power Drive Unit

PFD - Primary Flight Display

PLI - Pitch Limit Indicator

PMA - Permanent Magnetic Alternator

POP - Pilot Overhead Panel

PRV - Pressure Relief Valve

PSI - Pounds per Square Inch

PSID - Pounds per Square Inch Differential

PTT - Push To Talk

PTU - Power Transfer Unit

PWS - Potable Water System


QRH - Quick Reference Handbook


RAAS - Runway Awareness Advisory System

RAT - Ram Air Turbine

RDC - Remote Data Concentrator

REER - Right Electronic Equipment Rack

REU - Remote Electronics Unit

RIU - Remote Interface Unit

RPM - Revolutions Per Minute

RNP - Required Navigation Performance

RVSM - Reduced Vertical Separation Minimums


SAT - Static Air Temperature

SAV - Starter Air Valve

SFD - Standby Flight Display

SMC - Standby Multifunction Controller

SPDS - Secondary Power Distribution System

SPU - Switch Panel Unit

SSEC - Static Source Error Correction

SSPC - Solid State Power Controller

SVS - Synthetic Vision System


TAT - Total Air Temperature

TCAS - Traffic Collision Avoidance System

TGT - Turbine Gas Temperature

TOGA - Take Off / Go Around

TPMS - Tire Pressure Monitoring System

TPMU - Tire Pressure Monitoring Unit

TROV - Thrust Recovery Outflow Valve

TRS - Thrust Reference System

TSC - Touch Screen Controller

TSS - Trim Speed Sync

TRU -Transformer Rectifier Unit


UPS - Uninterruptible Power Supply


VGP - Vertical Glide Path

VSD - Vertical Situation Display

VWS - Vacuum Waste System


WGS84 - World Geodetic Survey 1984

WOW - Weight On Wheels

Revision: 20190603