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Illustrated technical information covering Vol 2 Over 800 multi-choice systems questions Close up photos of internal and external components Illustrated history and description of all variants of 737 Databases and reports of all the major 737 accidents & incidents History and Development of the Boeing 737 - MAX General flightdeck views of each generation of 737's Technical presentations of 737 systems by Chris Brady Detailed tech specs of every series of 737 A collection of my favourite photographs that I have taken of or from the 737 Press reports of orders and deliveries Details about 737 production methods A compilation of links to other sites with useful 737 content Study notes and technical information A compilation of links to major 737 news stories with a downloadable archive A quick concise overview of the pages on this site


This is a list of abbreviations commonly used throughout the site. It is my intention to expand this section into a glossary, cross-referenced with the rest of the site.

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AC: Alternating Current

ACARS: Aircraft Communications Addressing and Reporting System

ACT: Active

ADC: Air Data Computer - Classics

ADF: Automatic Direction Finder

ADIRS: Air Data Inertial Reference System

ADIRU: Air Data Inertial Reference Unit - NG's

ADM: Air Data Module

AFDS: Autopilot Flight Director System

AFM: Airplane Flight Manual

AGL: Above Ground Level

AI: Anti–Ice

AIL: Aileron

ALT: Altitude

ALTN: Alternate

ANP: Actual Navigation Performance

ANS: Alternate Navigation System

AOA: Angle of Attack

A/P: Autopilot

APU: Auxiliary Power Unit

ARINC: Aeronautical Radio, Incorporated

ARPT: Airport

ATA: Actual Time of Arrival

ATC: Air Traffic Control

ATT: Attitude

AUTO: Automatic

AVAIL: Available



BARO: Barometric

BRT: Bright

BTL DISCH: Bottle Discharge (fire extinguishers)

B/C: Back Course



C: Captain

C: Celsius

C: Center

CANC/RCL: Cancel/Recall

CB: Circuit Breaker

CG: Center of Gravity

CDU: Control Display Unit

CHKL: Checklist

CLB: Climb - FMC page

COMM: Communication

CON: Continuous

CONFIG: Configuration

CRZ: Cruise - FMC page

CSD: Constant Speed Drive

CTL: Control



DC: Direct Current

DDG: Dispatch Deviations Guide

DEP ARR: Departure Arrival

DES: Descent - FMC page

DEU: Display Electronic Unit

DISC: Disconnect

DME: Distance Measuring Equipment

DSP: Display Select Panel

DSPL: Display



E/D: End of Descent

EADI: Electronic Attitude Display Indicator

EEC: Electronic Engine Control

EFIS: Electronic Flight Instrument System

EGPWS: Enhanced Ground Proximity Warning System

EGT: Exhaust Gas Temperature

EHSI: Electronic Horizontal Situation Indicator

ELEC: Electrical

ELEV: Elevator

ENG: Engine

EO: Engine Out

EPR: Engine Pressure Ratio

EXEC: Execute

EXT: Extend

E/E: Electrical and Electronic



F: Fahrenheit

FADEC: Full Authority Digital Engine Control

FCTL: Flight Control

F/D or FLT DIR: Flight Director

FMC: Flight Management Computer

FMS: Flight Management System

F/O: First Officer

FOD: Foreign Object Damage

FPA: Flight Path Angle

FPV: Flight Path Vector



GA: Go–Around

GEN: Generator

GPS: Global Positioning System

GPWS: Ground Proximity Warning System

G/S: Glide Slope



HDG: Heading

HDG REF: Heading Reference

HDG SEL: Heading Select

HGS: Head-up Guidance System

HP: High Pressure

HPA: Hectopascals

HUD: Head-Up Display



IAS: Indicated Airspeed

IDENT: Identification - Transponder function

IDG: Integrated Drive Generator

IN: Inches

IND LTS: Indicator Lights

ILS: Instrument Landing System

INBD: Inboard

INOP: Inoperative

INTC CRS: Intercept Course

IRS: Inertial Reference System

ISLN: Isolation



K or Kts: Knots

KGS: Kilograms



L: Left

LBS: Pounds

LDG ALT: Landing Altitude

LIM: Limit

LNAV: Lateral Navigation

LP: Low Pressure

LWR CTR: Lower Center

LWR DSPL: Lower Display



MAG: Magnetic

MAN: Manual

MCP: Mode Control Panel

MDA: Minimum Descent Altitude

MEL: Minimum Equipment List

MIN: Minimum

MMO: Maximum Mach Operating Speed

MOD: Modify

MTRS: Meters



NAV RAD: Navigation Radio

ND: Navigation Display

NG: Next Generation - 737 Series 600, 700, 800, 900, BBJ1 or BBJ2.

NM: Nautical Miles

NORM: Normal

N1: Low Pressure Rotor (Fan) Speed

N2: High Pressure Rotor (Core) Speed



OHU: Overhead Unit

OUTBD DSPL: Outboard Display

OVHD: Overhead

OVRD: Override



PASS: Passenger

Pax: Passengers

PCU: Power Control Unit

PERF INIT: Performance Initialization - FMC page

PF: Pilot Flying

PFC: Primary Flight Computers

PFD: Primary Flight Display

PNF: Pilot Not Flying

PNL: Panel

POS: Position

POS INIT: Position Initialization - FMC page

PRI: Primary

PSEU: Proximity Switch Electronic Unit

PSU: Passenger Service Unit

PTU: Power Transfer Unit

PWS: Predictive Windshear System



R: Right

RA: Radio Altitude

RA: Resolution Advisory

RECIRC: Recirculation

REF: Reference

RET: Retract

RF: Refill

RNP: Required Navigation Performance

RTO: Rejected Take-Off



S/C: Step Climb

SEL: Select

SPD: Speed

STA: Station

STAB: Stabilizer

STAT: Status

STD: Standard



T or TRU: True

T or TK or TRK: Track

TA: Traffic Advisory

TAT: Total Air Temperature

TCAS: Traffic Alert and Collision Avoidance System

TDZE: Touch Down Zone Elevation

T/D: Top of Descent

TFC: Traffic

THR HOLD: Throttle Hold

TO: Takeoff

TO/GA: Takeoff/Go–Around



UPR DSPL: Upper Display

UTC: Universal Time Coordinated



VMO: Maximum Operating Speed

VNAV: Vertical Navigation

VOR VHF: Omnidirectional Range

VR: Rotation Speed

VREF: Reference Speed

VSCF: Variable Speed Constant Frequency

VSD: Vertical Situation Display

VTK: Vertical Track

V/S: Vertical Speed

V1: Takeoff Decision Speed

V2: Scheduled Takeoff Target Speed



WPT: Waypoint

WXR: Weather Radar



XTK: Cross Track


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