1Dk4eXg

AWPA
AWPA Australian Women Pilots’ Association [office,
Crafers, SA].
AWPG Advanced weather products generator.
AWR Airborne weather radar.
AWRA Augmentor-wing research aircraft.
AWRE Atomic Weapons Research Establishment
[Aldermaston, now AWE] (UK).
AWRS 1 Airborne weather reconnaissance system
(USAF).
2 Automatic weather reporting system.
AWS 1 Air Weather Service (USAF, formerly part of
MAC, now an FOA, Scott AFB).
2 Audible (or advanced) warning system.
3 Automatic wing sweep.
4 Air ward system.
5 Area weather system.
6 Aircraft Warning Service (USA/USN, 1942 – 46).
Awsacs, AWSACS All-weather stand-off aircraft (or
attack) control system (USN).
AWSAS All-weather stand-off attack system.
AWSO Aviation-warfare systems operator.
AWT 1 Airborne wideband terminal.
2 Atmospheric wind tunnel.
AWT Tail-on-wing aerodynamic influence coefficient.
AWTA Advise what time available.
AWTSS All-weather tactical strike system.
AWW All-, or alert, weather watch.
AWW Wing-on-wing aerodynamic influence coefficient.
AWX All-weather interceptor.
AWY, awy Airway (ICAO, FAA).
AX 1 Avionics, avionics control (USAF).
2 Int. classes of hot-air balloons, from AX3 [20,000 cu
ft, 566 m 3 ] to AX9 [140,000 cu ft, 3,935 m 3 ].
AXAF Advanced X-ray astrophysics facility.
AXBT Air- [or aircraft-] launched bathythermograph.
axes Aircraft attitude is described in terms of three sets of
*. First set are reference *, also called body *,three mutually
perpendicular directions originating at c.g. (point O and
defined as longitudinal (roll) axis OX, measured positive
forwards from O and negative to rear; transverse (pitch)
axis OY, measured positive to right and negative to left; and
vertical (yaw) axis OZ, measured positive downwards and
negative upwards. Position of O defined at design stage in
what is considered most likely location for real c.g. in
practice. Second, single, * is wind *: direction of relative
wind, drawn through O, has angle determined by flight
velocity, angle of attack and angle of sideslip. Third * are
those known as inertia * and are imaginary lines about
which aircraft would actually rotate in manoeuvres. These
need not be same as reference *, although OY and OZ
inertia axes are usual closely co-incident unless aircraft is
asymmetrically loaded. Principal inertia *, however, may
often depart substantially from geometrically drawn foreand-aft
axis OX (see inertia coupling). Purists distinguish
between stability axes for aircraft (a special set of body
axes) and those for tunnel testing.
AX-5 Space suit for post-1989 Shuttle operations
(NASA).
axial cable 1 In non-rigid airship, main longitudinal
member linking supporting cables, in framework carrying
crew and engines.
2 In rigid airship, essentially straight cable sometimes
linking extreme nose and tail of hull and central fittings of
radial or diametral wires.
azimuth control
axial compressor Compressor for air or other fluid with
drum-shaped rotor carrying one or more rows of radial
blades in form of small aerofoils (airfoils) arranged to
rotate around central axis, with row of stationary stator
blades (vanes) between each moving row. Compressed
fluid moves through alternate fixed and moving blading
in essentially axial direction, parallel to axis of rotation,
temperature and pressure increased at each stage.
axial cone In rigid airship, fabric cone at front and rear
of each gas cell providing flexible gas-tight connection
between cell and axial cable.
axial cord In parachute, central rigging line joining apex
to eyes formed at lower extremities of rigging lines.
axial deck In ship carrying or serving as operating
platform for aircraft, flight deck aligned fore and aft.
axial engine Usually, piston engine in which axes of
cylinders are parallel to crankshaft and/or main output
shaft. Also, loosely, axial-flow engine.
axial firing Fixed to fire directly ahead (usually on helicopters).
axial-flow engine Gas-turbine engine having predominantly
axial compressor, esp. one in which airflow is
essentially axial throughout (ie, not reverse-flow).
axial focusing In supersonic wind tunnel, focusing of
shockwaves reflected from tunnel wall on to principal
axis. Usually condition to be avoided, typically by
minimising such reflections or so shaping working section
that they are dispersed in different planes.
axial velocity ratio In an axial-flow engine, ratio of axial
flow velocity Va to turbine rotor blade velocity U, Va/U.
Also called flow coefficient.
axis of rotation In rotorplane, apparent axis about
which main lifting rotor rotates: line passing through
centre of tip-path circle and perpendicular to tip-path
plane. May be widely divergent from mechanical axis on
which hub is mounted, especially in articulated rotor.
axis of symmetry Usually aeronautical *** determined
by geometrical form, but in some cases dictated by mass
distribution.
Ay 1 Direct sideforce, changing heading without bank
or sideslip.
2 Any lateral acceleration.
AYY A half-width cargo container for upper deck of a
narrow-body aircraft.
Az Generalised symbol, azimuth.
Az-El, Azel, Az/El Radar presentation giving separate
pictures of azimuth (PPI display, or chosen sector) and
elevation (such as side view of glide path).
azication Azimuth indication.
azimuth 1 Horizontal bearing or direction; thus * angle.
2 Rotation about vertical axis (yaw is preferred term
where motion is that of whole aircraft).
3 Bearing of celestical body measured clockwise from
true North, often called * angle and qualified true,
compass, grid, magnetic or reference, depending on
measure used.
azimuth aerial Ground radar aerial rotating about
vertical axis, or sending out phased-array emission
rotating about such axis, intended to measure target
azimuth angles.
azimuth compiler Portion of SSR system, often optional
or absent, which provides accurate azimuth information
more accurately than the normal plot extractor.
azimuth control In rotorplane, cyclic pitch.
81