U.S. DEPARTMENT OF TRANSPORTATION
FEDERAL AVIATION ADMINISTRATION
Air Traffic Organization Policy

ORDER
JO 7340.2D
Effective Date:
April 3, 2014
 
     

Subject:  Contractions
       Includes: Change 1 effective 8/22/13, Change 2 effective 12/12/13, and Change 3 effective
       4/3/14
 
 

[Back to Section 2. Encode]

U

Definition

Contraction

Usage

U.S. Air Force

USAF

GEN

U.S. Army

USA

GEN

U.S. Army Aviation Flight Information

USAFIB

GEN

U.S. Coast Guard

USCG

GEN

U.S. Marine Corps

USMC

GEN

U.S. Navy

USN

GEN

ultra high frequency

UHF

ICAO

ultra high frequency direction finding station

UDF

ICAO

Unable

UN

GEN

Unable

UNA

ICAO

unable higher altitude

UHA

ATC

unable higher due opposite direction traffic

UHDODT

ATC

unable higher due same direction traffic

UHDSDT

ATC

unable higher due traffic

UHDT

ICAO

unable higher due traffic

UHDT

ICAO

unable lower due traffic

ULDT

ATC

unable to approve

UNAP

ICAO

unable to approve

UNAPV

GEN

unable to approve altitude requested

UNAR

ATC

unable to approve arrival for the time specified

UA

ATC

unable to approve departure for the time specified

UD

ATC

unable to approve route requested

UNRR

ATC

unable to contact company radio

UNCC

ATC

unable to establish contact

UNTC

ATC

unable to finish

INSUF

GEN

unable to maintain

UM

ATC

unable to monitor

UNMON

GEN

unable to transmit

NIL

GEN

Unattended

UNATNDD

GEN

Unavailable

UNAVBL

GEN

uncertainty phase code (alerting service)

INCERFA

ATC

Undelivered

UNDLD

GEN

Unheard

UNHRD

GEN

Unidentified

UNID

GEN

unidentified flying object

UFO

GEN

United States Naval Observatory

USNO

ATC

United States NOTAM Office

USNOF

GEN

United States NOTAM System

USNS

GEN

unknown

UNKN

GEN

unknown precipitation

UP

METAR

unlighted

UNLGTD

GEN

unlimited

UNL

ICAO

unmonitored

UNMON

ATC

unnecessary

UNEC

GEN

unofficial

UNOFFL

GEN

unquote

UQOT

GEN

unreadable

UNRDBL

GEN

unreliable

UNREL

ICAO

unreliable

UNRELBL

GEN

unrestricted

UNRSTD

GEN

unsatisfactory

UNSATFY

GEN

unscheduled

UNSKED

GEN

unseasonable

UNSBL

NWS

unserviceable

U/S

ICAO

unsettle

UNSTL

NWS

unstable

UNSTBL

NWS

unsteady

UNSTDY

NWS

until

TIL

GEN

until advised by

UAB

ATC

until advised by the tower

UAT

ATC

until cleared down

UCDWN

ATC

until cleared to land by the tower

UCLT

ATC

until further advised

UFA

GEN

until further notice

UFN

GEN

until past

TIP

ATC

untra long range

ULR

ICAO

unusable

UNUSBL

GEN

up and down drafts

UDDF

NWS

up drafts

UPDFTS

NWS

update

UPDT

NWS

upper

UPR

NWS

upper air route

UAR

ICAO

upper area control center

UAC

ICAO

upper atmosphere geophysics

UAG

NWS

upper control area

UTA

ICAO

upper flight information region

UIR

ICAO

upper information center

UIC

ICAO

upper winds

UWNDS

NWS

upper winds obs. (by radio methods)

RAWIN

NWS

upslope

UPSLP

NWS

upstream

UPSTRM

NWS

upward vertical velocity

UVV

NWS

upwind

UW

ATC

urgent

URG

GEN

urgent PIREP

UUA

ATC

urgent special observation (weather reports only)

USP

NWS

usable

USBL

GEN

User Equivalent Range Error

UERE

ATC

 

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