ABBREVIATION	DESCRIPTION
AAL	Above Aerodrome Level
AGL	Above Ground Level
AH / AI	Artificial Horizon / Attitude Indicator
AIP	Aerodrome Information Publication (a comprehensive series of operational documents for VHF and IFR pilots)
AMSL	Above Mean Sea Level
ARFOR	Area Forecast
ASI	Air Speed Indicator
ATC	Air Traffic Control
AVGAS	Aviation Gasoline
BAK	Basic Aeronautical Knowledge
CASA	Civil Aviation Safety Authority
CAVOK	Ceiling And Visability OK
CFI	Chief Flying Instructor
CG	Centre of Gravity
CHT	Cylinder Head Temperature
CIR	Command Instrument Rules
CPL	Commercial Pilot's Licence
CTA	Control Area / Controlled Airspace
CTAF	Common Traffic Advisory Frequency
CTZ	Control Zone
DA	Density Altitude
DG / DI	Directional Gyro(scope) / Direction Indicator
EGT	Exhaust Gas Temperature
ELT	Emergency Location/Locator Transmitter
ERSA	Enroute Supplement Australia (an aerodrome directory and useful reference publication)
ETA	Estimated Time of Arrival
FIA / FIR / FIS	Flight Information Area / Flight Information Region / Flight Information Service
FPM	Feet per Minute (rate of Climb or Decent)
GA	General Aviation
GAAP	General Aviation Aerodrome Procedures
GFPT	General Flying Progress Test
GMT	Greenwich Mean Time - same as UTC and Z
GS	Ground Speed - the speen of the aircraft relative to a point on the ground. It is a resultant (combination) of True Air Speed and Wind velocity
IAS	Indicated Air Speed - the speed of the aircraft as shown on the Air Speed Indicator
IFR	Instrument Flight Rules
ILS	Instrument Landing System
IMC	Instrument Meteorological Conditions (IMC exists if VMC do not)
ISA	International Standard Atmosphere
kHz	kilohertz, radio frequency expressed in thousands of cycles per second
KIAS	Knots, Indicated Air Speed
KTAS	Knots True Air Speed
L/D	Lift/Drag ratio
LAME	Licenced Aircraft Maintenance Engineer
LMT	Local Mean Time
LSALT	Lowest Safe Altitude
MAP	Manifold absolute Pressure (this is measured in inches of mercury - in./hg.). Together with RPM gives a measure of engine power
MBZ	Manditory Broadcast Zone
MET	Meteorology - generally refers to weather conditions and forecasts.
MP	Manifold Pressure
MHz	MegaHertz - radio frequency in millions of cycles per second
NDB	Non-Directional Beacon
NOTAM	Notice to Airmen, advising status of airspace, navigational aids, hazzards, etc.
NVFR	Night Visual Flight Rules (expressed as Night VFR - same usage as NVMC)
NVMC	Night Visual Meteorological Conditions (expressed as Night VMC)
OCTA	Outside Controlled Airspace or Uncontrolled Airspace (same as Class G airspace)
PAX	Passengers
PIC	Pilot In Command
POB	Persons On Board
POH	Pilot's Operating Handbook - also refered to as the Flight Manual
PPL	Private Pilot's Licence
PRD	Prohibited, Restricted and Dangerous areas
PSI	Pounds per Square Inch - pressure
PTT	Press To Talk (or Transmit) - button for external radio transmissions
PVT	Private category flight (as distinct from charter, airwork, RPT)
QNH	Altitude pressure datum to show vertical distance above local mean sea level
RIS	Radar Information Service
RBI	Relative Bearing Indicator - Clock Code in Degrees
RMI	Radio Magnetic Indicator
ROC	Rate Of Climb
ROD	Rate Of Descent
RPM	Revolutions Per Minute
RPT	Regular Public Transport
RWY	Runway
SARTIME	Time after which search begins
SARWATCH	Monitoring of a flight to activate emergency services if not cancelled by a specific time
SIGMET	Significant weather warning
SMC	Surface Movement Control - the areodrome trafficv control agency for all ground operatins, including land vehicles
TAF	Terminal Aerodrome Forecast
TAS	True Air Speed
TR	Track over the ground
TWR	Control Tower
Unicom	Universal Communications, a secondary function of some CTAF/MBZ frequencies
USG	United States of America Gallon
UTC	Universal Coordinated Time - same as GMT or Z
VFG	Visual Flight Guide (an ATC compendium of useful information for VFR pilots)
VFR	Visual Flight Rules
VHF	Very High Frequency - Radio Band
VMC	Visual Meteorological Conditions - good weather
VSI	Vertical Speed Indicator - rate of climb or descent indicator in units of hundreds of feet per minute
VTC	visual terminal chart - scale 1:250,000
W/V	Wind Velocity - direction from and speed
WAC	World Aeronautical Chart - universal topographical chart - scale 1:1,000,000
WX	Weather
XW	Crosswind
Z	Zulu time zone - same as GMT or UTC