Contraction

Definition

Usage

X

Cross

ICAO

X

obscured sky condition

NWS

XBAR

crossbar

ICAO

XCP

except

NWS

XFSS

Auxiliary Flight Service Station

ATC

XH

special handling service for aircraft

GEN

XNG

crossing

ICAO

XPC

expect

NWS

XPLOS

explosive

GEN

XREP

auxiliary report

GEN

XS

atmospherics

ICAO

XTAL

crystal

GEN

XTLK

cross talk

ATC

XW

crosswind

ATC

XX

heavy (to qualify weather phenomena, e.g. XXRA - heavy rain)

ICAO