A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Y

Z

 
I

i -   i = square root of (-1)
'I' -   See inphase
IA - Iowa
IAO - In and out of clouds
IC -   Ice Crystals, Diamond dust (very small ice crystals in suspension), or  In-Cloud Lightning
ICAO -   International Civil Aviation Organization
ICE - Icing
ICG - Icing
ICGIC - Icing in clouds
ICGIP - Icing in precipitation
ID - Identifier, identify, or Idaho
IFFDP -   International Flight Folder Documentation Program
IFLOWS -   The Integrated Flood Observing and Warning System.
IFR - Instrument Flight Rules
IL - Illinois
IMC - Instrument meteorological conditions
IMDT - Immediate
IMDTLY - Immediately
IMPL - Impulse
IMPLS - Impulses
IMPR - Improve or improving
IMPT - Important
IMT - Immediate or immediately
INBD - Inbound
INC - In cloud
INCL - Include
INCLD - Included
INCLG - Including
INCLS - Includes
INCR - Increase
INCRD - Increased
INCRG - Increasing
INCRGLY - Increasingly
INCRS - Increases
INDC - Indicate
INDCD - Indicated
INDCG - Indicating
INDCS - Indicates
INDEF - Indefinite
INFO - Information
INLD - Inland
INOP - Inoperative
INP - If not possible
INPR - In progress
INS -   Inertial Navigation System
INSTBY - Instability
INSTF - Intensify or intensifying
INSTL - Install or installed or installation
INTCNTL - Intercontinental
INTL - International
INTMD - Intermediate
INTMT - Intermittent
INTMTLY - Intermittently
INTR - Interior
INTRMTRGN - Intermountain region
INTRP - Interupt or interruption or interrupted
INTS - Intense
INTSFCN - Intensification
INTSFY - Intensify
INTSFYD - Intensified
INTSFYG - Intensifying
INTSFYS - Intensifies
INTST - Intensity
INTSTY - Intensity
INTVL - Interval
INU -  Inertial Navigation Unit
INVOF - In vicinity of
INVRN - Inversion
IOVC - In overcast
IP - Ice pellets
IPV - Improve
IPVG - Improving
IR -   Infrared or Ice on runway
ISA - International standard atmosphere
ISOL - Isolated or Isolate
ISOLD - Isolated
ITCZ -   Intertropical Convergence Zone  


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.