A
- A/FD
- A/G
- A/HA
- AAF
- AAI
- AAP
- AAR
- ABDIS
- ABN
- ABV
- ACAIS
- ACARS
- ACAS
- ACC
- ACCT
- ACCUM
- ACD
- ACDO
- ACF
- ACFO
- ACFT
- ACI-NA
- ACID
- ACIP
- ACLS
- ACLT
- ACO
- ACO
- ACR
- ACRP
- ACS
- ACT
- ADA
- ADAP
- ADAS
- ADCCP
- ADDA
- ADF
- ADI
- ADI
- ADIN
- ADIZ
- ADJ
- ADL
- ADLY
- ADO
- ADP
- ADS
- ADSIM
- ADSlM
- ADSY
- ADTN
- ADTN2000
- ADVO
- ADZD
- AERA
- AEX
- AF
- AFB
- AFIS
- AFP
- AFRES
- AFS
- AFSFO
- AFSFU
- AFSOU
- AFSS
- AFTN
- AGIS
- AGL
- AID
- AIG
- AIM
- AIRMET
- AIRNET
- AIS
- ALP
- AlP
- ALS
- ALSF1
- ALSF2
- ALSIP
- ALSTG
- ALT
- AlT
- ALT
- ALTM
- ALTN
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- AMASS
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- AMVER
- ANC
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- ANG
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- ANMS
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- AP
- APCH
- APL
- APP
- APS
- AQAFO
- ARAC
- ARCTR
- ARF
- ARFF
- ARINC
- ARLNO
- ARO
- ARP
- ARR
- ARRA
- ARSA
- ARSR
- ARTCC
- ARTS
- ASAS
- ASC
- ASCP
- ASD
- ASDA
- ASLAR
- ASM
- ASOS
- ASP
- ASPH
- ASQP
- ASR
- ASTA
- ASV
- AT
- ATA
- ATAS
- ATC
- ATCAA
- ATCBI
- ATCCC
- ATCO
- ATCRB
- ATCRBS
- ATCSCC
- ATCT
- ATIS
- ATISR
- ATM
- ATMS
- ATN
- ATODN
- ATOMS
- ATOVN
- ATS
- ATS
- ATSCCP
- AUTH
- AUTOB
- AUTODIN
- AUTOVON
- AVBL
- AVN
- AVON
- AWlS
- AWOS
- AWP
- AWPG
- AWS
- AWY
- AZM
B
C
- C/S/S/N
- CAA
- CAAS
- CAB
- CARF
- CASFO
- CAT
- CAU
- CBAS
- CBI
- CBSA
- CC&O
- CCAS
- CCC
- CCCC
- CCCH
- CCLKWS
- CCS7-NI
- CCSA
- CCSD
- CCU
- CD
- CDAS
- CDR
- CDSA
- CDT
- CDTI
- CEAS
- CENTX
- CEP
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- CFC
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- CTC
- CTL
- CTMA
- CUPS
- CVFR
- CVTS
- CW
- CWSU
- CWY
D
E
F
H
I
L
M
N
- N
- NA
- NAAQS
- NADA
- NADIN
- NADSW
- NAILS
- NAILS
- NAMS
- NAPRS
- NAS
- NASA
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- NB
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- NE
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- NR
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O
P
R
- RAIL
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- RBC
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- RCC
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- REC
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- RL
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- RMCC
- RMCF
- RML
- RMLR
- RMLT
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- RNAV
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- RP
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- RSA
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- RT
- RT & BTL
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- RTRD
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- RUF
- RVR
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- RW
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- RWY
S
- S
- S/S
- SA
- SAC
- SAFI
- SALS
- SAT
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- SAWR
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- SB
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- SN
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- SPD
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- SSALF
- SSALR
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- SSB
- SSR
- STA
- STAR
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- STMUX
- STOL
- SUN
- SURPIC
- SVC
- SVCA
- SVCB
- SVCC
- SVCO
- SVFB
- SVFC
- SVFD
- SVFO
- SVFR
- SW
- SWEPT