|
Contraction
|
Definition
|
Usage
|
|
I/IFR
|
intermittent instruments
|
ATC
|
|
IAARC
|
International Administrative
Aeronautical Radio Conference
|
GEN
|
|
IAATCD
|
if authorized by ATC, DME may be used
|
ATC
|
|
IAC
|
instrument approach chart (followed by
name/title)
|
ICAO
|
|
IAF
|
initial approach fix
|
GEN
|
|
IAO
|
in and out of clouds
|
ICAO
|
|
IAP
|
instrument approach procedure
|
ICAO
|
|
IAR
|
intersection of air routes
|
ICAO
|
|
IAS
|
indicated air speed
|
ATC
|
|
IATA
|
International Air Transport Association
|
GEN
|
|
IATSC
|
International Aeronautical
Telecommunications Switching Center
|
GEN
|
|
IAW
|
in accordance with
|
GEN
|
|
IBASF
|
intervals between aircraft in stream
type formation
|
ATC
|
|
IBN
|
identification beacon
|
ICAO
|
|
IBND
|
inbound
|
ATC
|
|
IC
|
ice crystals (weather reports only)
|
METAR
|
|
IC
|
icing (PIREP only)
|
ATC
|
|
ICAO
|
International Civil Aviation
Organization
|
GEN
|
|
ICD
|
Interface Control Document
|
ATC
|
|
ICG
|
icing
|
NWS
|
|
ICGIC
|
icing in clouds
|
NWS
|
|
ICGICIP
|
icing in clouds and precipitation
|
NWS
|
|
ICGIP
|
icing in precipitation
|
NWS
|
|
ID
|
identify or identifier |
ICAO
|
|
IDAT
|
interfacility data
|
GEN
|
|
IDENT
|
identification
|
ICAO
|
|
IDP
|
individual development plan
|
GEN
|
|
IF
|
intermediate approach fix
|
ICAO
|
|
IF
|
intermediate fix
|
GEN
|
|
IFAMP
|
if approach missed proceed
|
ATC
|
|
IFF
|
identification friend/foe
|
ICAO
|
|
IFHOL
|
if holding
|
ATC
|
|
IFIM
|
International Flight Information Manual
|
GEN
|
|
IFINS
|
if instrument conditions encountered
|
ATC
|
|
IFO
|
International Field Office
|
GEN
|
|
IFO
|
interphone
|
GEN
|
|
IFONO
|
interphone (service F) not operative
|
GEN
|
|
IFORO
|
interphone (service F) resumed operation
|
GEN
|
|
IFPFP
|
individual flight plans from this point
|
ATC
|
|
IFR
|
instrument flight rules
|
ICAO |
|
IFSS
|
International Flight Service Station
|
GEN
|
|
IFUN
|
if unable
|
GEN
|
|
IFVLS
|
if flight visibility becomes less than
|
ATC
|
|
IFVR
|
if visibility remains
|
ATC
|
|
IGA
|
international general aviation
|
ICAO
|
|
IGIA
|
Interagency Group on International
Aviation
|
GEN
|
|
IIA
|
if incorrect advise
|
GEN
|
|
IISD
|
if incorrect service direct
|
GEN
|
|
ILAS
|
instrument low approach
|
ATC
|
|
ILS
|
instrument landing system
|
GEN
|
|
ILSP
|
ILSpartial
|
GEN
|
|
IM
|
inner marker
|
ICAO
|
|
IMAP
|
immediately after passing
|
ATC
|
|
IMC
|
instrument meteorological conditions
|
GEN
|
|
IMDT
|
immediate
|
NWS
|
|
IMF
|
interrogation sign
|
GEN
|
|
IMG
|
immigration
|
ICAO
|
|
IMI
|
Intensity unknown (weather reports only)
|
ICAO
|
|
IMP
|
impracticable
|
GEN
|
|
IMPL
|
impulse
|
GEN
|
|
IMPR
|
improve
|
ICAO
|
|
IMPT
|
important
|
GEN
|
|
IMT
|
immediate or immediately
|
GEN
|
|
IN
|
inch
|
ICAO
|
|
INA
|
initial approach
|
ICAO
|
|
INADQT
|
inadequate
|
GEN
|
|
INATS
|
interruption of air traffic services
|
GEN
|
|
INBD
|
inbound
|
ICAO
|
|
INC
|
in clouds
|
ICAO
|
|
INC
|
incorporated
|
GEN
|
|
INCERFA
|
uncertainty phase code (alerting
service)
|
ATC
|
|
INCL
|
include
|
GEN
|
|
INCLV
|
inclusive
|
GEN
|
|
INCOMP
|
incomplete
|
GEN
|
|
INCOR
|
incorrect
|
GEN
|
|
INCR
|
increase
|
GEN
|
|
INDC
|
indicate
|
GEN
|
|
INDEF
|
indefinite
|
GEN
|
|
INDUS
|
industrial
|
GEN
|
|
INF
|
inland navigation facility
|
GEN
|
|
INFO
|
information
|
GEN
|
|
INIT
|
initial training
|
GEN
|
|
INLD
|
inland
|
NWS
|
|
INOF
|
if not off
|
GEN
|
|
INOP
|
inoperative
|
ICAO |
|
INP
|
if not possible
|
GEN
|
|
INPR
|
in progress
|
ICAO
|
|
INREQ
|
information request
|
GEN
|
|
INS
|
inertial navigation system
|
ICAO
|
|
INSP
|
inspect
|
GEN
|
|
INST
|
instrument
|
GEN
|
|
INSTA
|
instruments authorized
|
ATC
|
|
INSTA
|
interstate
|
GEN
|
|
INSTBY
|
instability
|
NWS
|
|
INSTL
|
install
|
GEN
|
|
INSTR
|
instruct
|
GEN
|
|
INSTR
|
instrument
|
ICAO
|
|
INSUF
|
insufficient scheduled time available
|
GEN
|
|
INSUF
|
unable to finish
|
GEN
|
|
INT
|
intersection
|
ICAO
|
|
INTCNTL
|
intercontinental
|
GEN
|
|
INTCP
|
intercept
|
GEN
|
|
INTD
|
intend
|
GEN
|
|
INTER
|
intermittent
|
ICAO
|
|
INTFC
|
interference
|
GEN
|
|
INTL
|
international
|
ICAO
|
|
INTMD
|
intermediate
|
GEN
|
|
INTMT
|
intermittent
|
GEN
|
|
INTNS
|
intentions
|
GEN
|
|
INTR
|
interior
|
NWS
|
|
INTRG
|
interrogator
|
ICAO
|
|
INTRMTRGN
|
InterMountain Region
|
NWS
|
|
INTRP
|
interrupt
|
GEN
|
|
INTS
|
intense
|
NWS
|
|
INTSF
|
intensify or intensifying
|
ICAO
|
|
INTSFY
|
intensify
|
NWS
|
|
INTST
|
intensity
|
ICAO
|
|
INTVL
|
interval
|
GEN
|
|
INTXN
|
intersection
|
GEN
|
|
INVES
|
investigate
|
GEN
|
|
INVOF
|
in the vicinity of
|
ATC
|
|
INVRN
|
inversion
|
NWS
|
|
INVSTAR
|
investigate and report
|
GEN
|
|
IOVC
|
in overcast
|
NWS
|
|
IP
|
initial point
|
ATC
|
|
IP
|
instructor pilot
|
GEN
|
|
IP/HHCL
|
initial point/Hhour control line
|
ATC
|
|
IPV
|
improve
|
GEN
|
|
IR
|
ice on runway
|
NWS
|
|
IR
|
IFR military training route
|
GEN
|
|
IRAC
|
Interdepartmental Radio Advisory
Committee
|
GEN
|
|
IRAD
|
inbound radial
|
ATC
|
|
IREG
|
irregular
|
GEN
|
|
IRN
|
Interface Revision Notices
|
ATC
|
|
IS
|
island
|
GEN
|
|
ISA
|
international standard atmosphere
|
ICAO
|
|
ISB
|
independent sideband
|
ICAO
|
|
ISMGR
|
Island Manager
|
GEN
|
|
ISMLS
|
interim standard microwave landing
system
|
GEN
|
|
ISOL
|
isolate
|
GEN
|
|
ITCK
|
issue time check
|
ATC
|
|
ITNRNT
|
itinerant
|
GEN
|
|
ITRY
|
itinerary
|
GEN
|
|
ITU
|
International Telecommunications Union
|
GEN
|
|
IVFRC
|
in VFR conditions
|
ATC
|
