Garmin G300 Pilot's Manual page 271

gal gallon(s)
Glide Ratio, The estimated distance an aircraft will move forward for
G/R any given amount of lost altitude.
GND ground
gph gallons per hour
GPS Global Positioning System
Grid MORA Grid Minimum Off-Route Altitude; one degree latitude
by one degree longitude in size and clears the highest
elevation reference point in the grid by 1000 feet for all
areas of the grid
Groundspeed The velocity that the aircraft is travelling relative to a
ground position.
Ground Track see Track
GS Ground speed
Heading The direction an aircraft is pointed, based upon indications
from a magnetic compass or a properly set directional gyro.
Hg mercury
hPa hectopascal
hr hour
HSI Horizontal Situation Indicator
Hz Hertz
IAF Initial Approach Fix
IAT Indicated Air Temperature
ICAO International Civil Aviation Organization
IFR Instrument Flight Rules
ILS Instrument Landing System
IMC Instrument Meteorological Conditions
in inch
190-00921-00 Rev. D Garmin G300 Pilot's Guide
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