SYMBOLS, ABBREVIATIONS AND TERMINOLOGY

CONTENT:

UNIVERSAL SYMBOLS AND ABBREVIATIONS
GENERAL AIRSPEED TERMINOLOGY AND SYMBOLS

METEOROLOGICAL TERMINOLOGY
POWER TERMINOLOGY

ENGINE TERMINOLOGY, CONTROLS AND INSTRUMENTS
AIRPLANE PERFORMANCE AND FLIGHT PLANNING TERMINOLOGY

WEIGHT AND BALANCE TERMINOLOGY


UNIVERSAL SYMBOLS AND ABBREVIATIONS

A B C D E F G H I J K L M N O P Q R S T U V W X

A

ampère

AC

alternating current

ADF

automatic director finding / finder

ADI

attitude director indicator

AGL

above ground level

ALT

altitude

AM

amplitude modulation

AMPS

ampères

ANT

antenna

ANTI-COLL

anti-collision

AP, A/P

autopilot

approx.

approximate

ARINC

Aeronautic Radio Incorporation, USA

ASA

anti-static additive

ASAP

as soon as possible

ASD

accelerate stop distance

ASI

attitude situation indicator

ASTM

American Society for Testing and Materials

ATC

air traffic control

ATT

attitude

auto

automatic

AVGAS

aviation gasoline

A B C D E F G H I J K L M N O P Q R S T U V W X

bar

1 bar @ 14.5 psi

BATT / BAT

battery

BFO

beat frequency oscillator

BRG

bearing

BRT

bright

B.S.

British Standard

A B C D E F G H I J K L M N O P Q R S T U V W X

°C

degrees centigrade

CAA

Civil Aviation Agency

CAB

cabin

C/B

circuit breaker

CCW

counter-clockwise

CDI

course deviation indicator

CDU

control display unit

C.G.

center of gravity

COMM

communication

COMB

combustion

CONS

consumption

CONTR

control

COPIL

copilot

CRS

course or cursor

cu ft

cubic foot, cubic feet

CW

clockwise or carrier wave

A B C D E F G H I J K L M N O P Q R S T U V W X

daN

deka (x100) Newton

DC

direct current

DCU

data conversion unit

DEFR

defrost (air)

DG

directional gyro

DH

decision height

D.Eng R.D.

Directorate Engineering Research Development (UK)

DIST

distance

DME

distance measuring equipment

DN, DWN

down

DO

Dornier

DR

dead reckoning

A B C D E F G H I J K L M N O P Q R S T U V W X

E

east

EAROM

electrically alterable read only memory

EGME

ethylene glycol monomethyl ether

ELT

emergency locator transmitter

EMERG/ EMG

emergency

END

endurance

ENG

engine

ESAD

equivalent still air distance

EWC

estimated wind component
(-  head wind)
(+ tail wind)

EXT

external or EXTING (extinguisher)

A B C D E F G H I J K L M N O P Q R S T U V W X

°F

degrees Fahrenheit

FAA

Federal Aviation Agency

FAR

Federal Aviation Regulation

FCU

fuel control unit

FDS

flight director system

FF

fuel flow

FLT

flight

FOD

foreign object damage

ft

foot, feet

ft/min

feet per minute

FRQ

frequency

F.S.I.I.

fuel system icing inhibitor

A B C D E F G H I J K L M N O P Q R S T U V W X

g

acceleration due to gravity

GA

go around or general aviation

GAL

gallon(s)

GEN

generator

GND

ground

GOV

governor

GS

glide slope or ground speed

A B C D E F G H I J K L M N O P Q R S T U V W X

h

hour

HDG

heading

HF

high frequency

HSI

horizontal situation indicator

HTR

heater

Hz

Hertz

A B C D E F G H I J K L M N O P Q R S T U V W X

ICAO

International Civil Aviation Organization

ICS

intercommunication system (intercom)

IFR

instrument flight rules

IGN

ignition

ILS

instrument landing system

IMC

instrument meteorological condition

in

inch, inches

in Hg

inches of Mercury

in lbs

inch pounds

INSTR

instrument(s)

ISA

International Standard Atmosphere

ITT

interturbine temperature, interstage turbine temperature

INVTR

inverter

A B C D E F G H I J K L M N O P Q R S T U V W X

JETT

jettison

A B C D E F G H I J K L M N O P Q R S T U V W X

kg

kilogram (1 kg @ 9.81 N @ 2.207 lbs)

kHz

kilo Hertz

kp

kilopond (1 kp @ 0.981 kg)

kt(s)

knot(s)

kW

kilowatt (1 kW @ 1.341 HP)

A B C D E F G H I J K L M N O P Q R S T U V W X

L

liter

LAND

landing

LBA

Luftfahrt – Bundesamt (German Federal Aviation Agency)

lb(s)

pound(s) (1 lb. @ 0.4536 kg)

LB-FT

foot pound, feet pound (torque)

LCM

list of consumable material

LH

left hand (side)

LOC

localizer

LP

low pressure

LSB

lower side band

LT(S)

light(s)

A B C D E F G H I J K L M N O P Q R S T U V W X

m, M

meter

m², M²

square meter

m³, M³

cubic meter

mA

milli ampère

MAC

mean aerodynamics cord

MAG/ magn.

magnetic

MAN

manual

max/ MAX

maximum

mb

millibar

MCP

maximum continuous power

MHz

Mega Hertz

mm

millimeter

Mil

military

MIN/ min

minimum

mkg

meterkilogram

MKR

marker

MSG

message

MSL

mean sea level

A B C D E F G H I J K L M N O P Q R S T U V W X

N

Newton or north

NATO

North Atlantic Treaty Organization

NAV

navigation

Ng

gas generator speed

NM

nautical miles

Np

power turbine (propeller) speed

A B C D E F G H I J K L M N O P Q R S T U V W X

OAT

outside air temperature

OBI

Omni bearing indicator

OBS

Omni bearing selector

A B C D E F G H I J K L M N O P Q R S T U V W X

PA/ PAX/ PASS

passenger

PCU

propeller control unit

PIL

pilot

PPH

pounds per hour (lbs/h)

PRESS

pressure

PROP

propeller

psi

pound per square inch (pressure)
a = absolute
d = differential
g = gauged

PTR

pointer

PTT

push to talk

PWR

power

A B C D E F G H I J K L M N O P Q R S T U V W X

QTY

quantity

A B C D E F G H I J K L M N O P Q R S T U V W X

recom

recommended

Ref/ REF

reference

REG

regulator

RELSE

release

RF

radio frequency

RH

right hand (side)

RLY

relay

RNAV

area navigation

RWY

runway

A B C D E F G H I J K L M N O P Q R S T U V W X

SAE

Society of Automotive Engineers

SB

seat belt

sec

seconds

SL

sea level

SPKR

speaker

SR

specific range

STBY

stand by

STOL

short takeoff and landing

SURF

surface

SW.OVR

switch over

SX

selected cross track

A B C D E F G H I J K L M N O P Q R S T U V W X

TAS

true airspeed

TBO

time between overhaul

TEMP

temperature

T.O.

takeoff

T/P

temperature-pressure

TQ

torque

TRANS

transfer

TRCVR

transceiver

T/S

turn and slip

A B C D E F G H I J K L M N O P Q R S T U V W X

USB

upper side band (or computer: Universal Serial Bus)

US GAL (gal)

United States gallons

A B C D E F G H I J K L M N O P Q R S T U V W X

V

speed or volts

VFR

visual flight rules

VG

vertical gyro

VHF

very high frequency

VLF

very low frequency

V/L

vapor liquid

VMTR

voltmeter

VOR

very high frequency omni directional range

VTOL

vertical takeoff and landing

A B C D E F G H I J K L M N O P Q R S T U V W X

WPT

way point

WSHLD

windshield

WX

weather

A B C D E F G H I J K L M N O P Q R S T U V W X

XMTR

transmitter

XPDR

transponder

W

VLF-Omega

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GENERAL AIRSPEED TERMINOLOGY AND SYMBOLS

CAS

Calibrated Airspeed is the indicated speed of an airplane, corrected for position and instrument error. Calibrated airspeed is equal to true airspeed in standard atmosphere at sea level.

KCAS

Calibrated Airspeed expressed in knots.

GS

Ground Speed is the speed of an airplane relative to the ground.

IAS

Indicated Airspeed is the speed of an airplane as shown on the airspeed indicator when corrected for instrument error. IAS values published in this handbook assume zero instrument error.

KIAS

Indicated Airspeed expressed in knots.

TAS

True Airspeed is the airspeed of an airplane relative to undisturbed air which is the CAS corrected for altitude, temperature, and compressibility.

VA

Maneuvering Speed is the maximum speed at which application of full available aerodynamic control will not overstress the airplane.

VFE

Maximum Flap Extended Speed is the highest speed permissible with wing flaps in a prescribed extended position.

VMC

Minimum Control Speed is the minimum flight speed at which the airplane is controllable with a bank of not more than 5° when critical engine suddenly becomes inoperative and the remaining engine is operating at emergency power and the propeller of the failed engine is windmilling.

VR

Rotation Speed is the speed at which rotation should be initiated to ensure liftoff at takeoff speed.

VSSE

Single Engine Speed is a speed above both VMC and stall speed, selected to provide a margin of lateral and directional control when one engine is suddenly rendered inoperative. For training purposes, intentional failing of one engine in flight at or above this speed is recommended.

VS

Stalling Speed or the minimum steady flight speed at which the airplane is controllable.

VSO

Stalling Speed or the minimum steady flight speed at which the airplane is controllable in the landing configuration (FLAPS 2).

VS1

Stalling Speed or the minimum steady flight speed obtained in a specific configuration.

Vx

Best Angle-of-Climb Speed is the airspeed which delivers the greatest gain in altitude in the shortest possible horizontal distance.

Vy

Best Rate-of-Climb Speed is the airspeed which delivers the greatest gain in altitude in the shortest possible time.

VMO

Maximum Operating Limit Speed is the speed limit that may not be deliberately exceeded in normal flight operations.

V2

Takeoff Safety Speed is the minimum speed to be obtained at 50 ft height.

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METEOROLOGICAL TERMINOLOGY

Altimeter Setting

Barometric Pressure corrected to sea level.

ISA

International Standard Atmosphere in which:
(1) The air is a dry perfect gas ;
(2) The temperature at sea level is 15° Celsius (59° Fahrenheit) ;
(3) The pressure at sea level is 29.92 inches of Mercury (1013.2 millibars) ;
(4) The temperature gradient from sea level to the altitude at which the temperature is -56.5°C (-69.7° F) is -0.00198° C (-0.003566° F) per foot (i.e. 36100 ft) and zero above that altitude.

OAT

Outside Air Temperature is the free air static temperature, obtained either from in-flight temperature indications adjusted for instrument error and compressibility effects, or from ground meteorological sources.

Indicated Pressure Altitude

The number actually read from an altimeter when the barometric subscale has been set to 29.92 inches of Mercury (1013.2 millibars). Position errors may be obtained from the Altimeter Correction graph.

Pressure Altitude

Altitude measured from standard sea level pressure (29.92 in. Hg) by a pressure (barometric) altimeter. It is the indicated pressure altitude corrected for position and instrument error. In this handbook altimeter instrument errors are assumed to be zero.

Station Pressure

Actual atmospheric pressure at field elevation.

Wind

The wind velocities plotted as variables on the charts of this handbook are to be understood as the headwind or tailwind components of the reported winds.

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POWER TERMINOLOGY

Emergency

Highest power rating not limited by time in single engine operation.

Takeoff

Highest power rating not limited by time.

Torque

An indication of power output of the engine.

HP

Horse Power.

SHP

Shaft Horse Power - in turboprop engines the amount of power delivered to the prop, disregarding any surplus thrust generated by the exhaust gases.

RPM

Revolutions Per Minute.

Reverse Thrust

The thrust produced when the propeller blades are rotated past flat pitch into the Beta range.

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ENGINE TERMINOLOGY, CONTROLS AND INSTRUMENTS

Beta Range

Engine operational mode in which propeller blade pitch is hydro mechanically controlled from the cockpit power Lever.

Igniter

A device (spark plug) used to start the burning of the fuel/air mixture in a combustion chamber.

Impeller

The main rotor of a radial compressor which increase the velocity of the air which it pumps.

Stator

A row of stationary airfoils which direct the airflow between the rows of rotor blades.

Turbine

A rotating device actuated either by reaction or impulse (or a combination of both), and used to transform some of the kinetic energy of the exhaust gases into shaft horse power to drive the compressor(s) and accessories.

Turboprop

A type of gas turbine that converts heat energy into propeller shaft work.

Power Lever

Cockpit Lever used to change propeller pitch during Beta operation and select engine fuel flow during propeller governing.

Condition Lever

Cockpit Lever providing inputs to fuel control.

Interstage Turbine Temperature (ITT)

Gas temperature measured between the compressor and power turbines.

Ng Tachometer (Gas Generator RPM)

The tachometer registers the RPM of the gas generator in %.

Np Tachometer (Propeller RPM)

The tachometer registers the propeller RPM up to a maximum of 1900 RPM.

Torque Meter

The instrument that indicates the torque (turning force) and thus power output of the engine.

Propeller Lever

Cockpit lever used to regulate the RPM of the propeller by increasing or decreasing the propeller pitch through a pitch change mechanism in the propeller hub.

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AIRPLANE PERFORMANCE AND FLIGHT PLANNING TERMINOLOGY

Climb Gradient

The ratio of the change in height during a portion of a climb, to the horizontal distance traveled in the same time interval.

Demonstrated Crosswind

The maximum 90° crosswind component for which adequate control of the airplane during takeoff and landing was actually demonstrated during certification tests.

Accelerate-Stop Distance

The distance required to accelerate an airplane to a specified speed and assuming failure of an engine at the instant that speed is attained, to bring the airplane to a stop.

Accelerate-Go Distance

The distance required to accelerate an airplane to a specified speed and, assuming failure of an engine at the instant that speed is attained, continue takeoff on the remaining engine to a height of 50 feet.

Landing Distance

The horizontal distance required to land from a 50 ft obstacle height and come to a complete stop.

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WEIGHT AND BALANCE TERMINOLOGY

Reference Datum

An imaginary vertical plane from which all horizontal distances are measured for balance purposes.

Station

A location along the airplane fuselage usually given in terms of distance from the reference datum.

Arm

The horizontal distance from the reference datum to the center of gravity (C.G.) of an item.

Moment

The product of the weight of an item multiplied by its arm. (Moment divided by a constant is used to simplify balance calculations by reducing the number of digits.)

Airplane Center of Gravity (C.G.)

The point at which an airplane would balance if suspended. Its distance from the reference datum is found by dividing the total moment by the total weight of the airplane.

C.G. Arm

The arm obtained by adding the airplane's individual moments and dividing the sum by the total weight.

C.G. Limits

The extreme center of gravity locations within which the airplane must be operated at a given weight.

Usable Fuel

Fuel available for flight planning.

Unusable Fuel

Fuel remaining after a runout test has been completed in accordance with governmental regulations.

Standard Empty Weight

Weight of a standard airplane including unusable fuel, full operating fluids and full oil.

Empty Weight

This is the Standard Empty Weight plus optional equipment, but not including the removable operational equipment (such as passenger seats in the cabin, stretchers etc.).

Basic Weight

Standard Weight plus optional equipment and modifications.

Payload

Weight of occupants, cargo, and baggage.

Useful Load

Difference between takeoff weight and empty weight.

Maximum Ramp Weight

Maximum weight for ground maneuver including fuel weight for start-up engines and taxi.

Maximum Takeoff Weight

Maximum weight approved for the start of the takeoff run.

Maximum Landing Weight

Maximum weight approved for the landing.

Maximum Zero Fuel Weight

Maximum weight exclusive of usable fuel.

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Taken from the Pilot's Operating Handbook (Revision 10 of 1 November 1983) of the Dornier 128-6 registered as "D-IBUF" and currently owned and flown by the Institute of Flight Guidance and Control of the University of Braunschweig, Germany.

Set into html format by Mathias Elsaesser ( Dornier1286@aol.com) in June 2001.