XYZ
X-ray |noun| 1. a ray with a very short
wavelength, which is invisible, but can go through soft tissue or material and
register as a photograph on a film 2. a
photograph taken using X-rays - |verb| to take an X-ray photograph of luggage
yard |noun| a unit of length in the US and
British Imperial Systems equal to 3 ft or 0.9144 m. Abbreviation: yd
yaw |noun| rotation of the aircraft around
its vertical axis / Three-axis control of roll, pitch and yaw is effected by
ailerons, elevators and rudder. / - |verb| to rotate around the vertical axis /
Single-engine, propeller-driven aircraft tend to yaw on take-off. /
yaw control |noun| the control of
the aircraft about the vertical axis managed mainly by the rudder
yaw damper |noun| a flight control
system which sends inputs to the rudder in order to counter the effects of
turbulence and avoid the aircraft oscillating from side to side, which is
called Dutch roll. If the yaw damper fails the aircraft may suffer from Dutch
roll.
yellow system |noun| one of the three
hydraulic systems (green, blue, yellow) on Airbus aircraft. Boeing identify
their hydraulic systems numerically.
yoke |noun| 1. a type of aircraft control
column by which the pilot controls ailerons by rotating a device on top of the
column to the left or right / Rotate the yoke to the left to roll the aircraft
to the left. / 2. a supporting structure like the forked metal mounting for the
nose-wheel / The yoke was damaged in the incident. /
Z |abbreviation| Zulu time
zero |noun| nought or the figure 0 / If the
atmospheric pressure at an airfield is 1,000 millibars (mb) and this pressure
is set on the sub-scale of an aircraft altimeter, then when that aircraft
touches down at the airfield, the altimeter will read zero. /
zero deviation signal |noun| a signal which
indicates that the aircraft is correctly aligned on the ILS and should not be
confused with no deviation signal, which means that no information is displayed
zero-zero |adjective| referring to flying
conditions of thick, low cloud when a pilot can see nothing ahead and nothing
above or below the aircraft
zonal |adjective| referring to one of the
five parts into which the Earth’s surface is divided by imaginary lines
parallel to the equator / The circulation of air around the Earth is zonal in
character. /
zone |noun| 1. an area with particular
features or purpose 2. an administrative
area of airspace / control zone, aerodrome traffic zone (ATZ) / 3. one of five
divisions into which the Earth’s surface is divided by imaginary lines parallel
to the equator / temperate zone, climatic zone /
zoom |verb| to make an aircraft climb rapidly
at a very steep angle, or move upwards in this way
Zulu time |noun| - Greenwich
Mean Time
