1Dk4eXg

AUF
AUF 1 Airborne use of force (USCG).
2 Australian Ultralight Federation [Canberra ACT].
AUFP Average unit flyaway price.
auger in To crash, esp.. to fly into ground.
augmentation 1 Boosting propulsive thrust by auxiliary
device, esp. by afterburning in both core and bypass flows
of turbofan.
2 Percentage of thrust added by (1).
3 Increasing inadequate natural flight stability of aerodyne
by on-board system driving control surfaces (rarely,
ad hoc auxiliary surfaces).
4 Enhancing target signature of radar, optical, IR or
other radiation by means of corner reflectors, Luneberg
lenses or other * devices.
5 Enhancement of fluid flow by ejector effect, esp.. of
lift airflow in powered-lift aircraft.
augmentation choke Pilot-controlled modulating valve
in blowing system of CCW for roll control.
augmentation ratio Ratio of total fluid flow to mass flow
of primary ejector flow of hot gas in ejector-lift system.
augmented deflector (or deflected) exhaust nozzle Nozzle
of V/STOL jet engine downstream of augmentor and
capable of deflecting flow through at least 90°C.
augmented turbojet, turbofan Engine equipped with
afterburning (reheat) to augment thrust, esp. at transonic
or supersonic flight speed. Turbofan augmentation may
be in hot and/or cold flows, latter offering greater density
of free oxygen.
augmentor Afterburner for turbofan, with burning in
hot and cold flows; US often augmenter.
augmentor ejector Main lifting system in ejector lift.
augmentor wing General term for STOL aeroplane wing
in which engine thrust is directly applied to augment circulation
and thus lift. Countless variations, but most
fundamental division is into external and internal
blowing. Former typically uses engine bleed air (rarely,
total efflux) discharged at sonic speed through one or
more narrow slits ahead of large double or triple-slotted
flaps which, because of blowing, can be depressed to
unusually sharp angle. Second method uses either engine
bleed air or total efflux to blow through flap system itself
(or propulsion engines are distributed across main flap, in
some schemes there being as many as 48 small engines).
Internal blowing makes flow separation impossible and
gives large downwards component of thrust, but is difficult
to apply and may severely compromise aircraft in
cruise (see jet flap, blown flap, externally blown flap, uppersurface
blowing).
AULD Aircraft unit-load device.
AUM 1 Air-to-underwater missile (USA DoD weapon
category).
2 All-up mass.
AUP 1 Advanced unitary penetrator.
2 Avionics upgrade program.
3 Airspace use plan.
4 Active unmanned vehicle phenomenology (AFRL).
AUR 1 All-up round.
2 Airplane [aircraft, aeroplane] upset recovery.
AURA 1 Advanced UHF radar.
2 Autonomous unmanned reconnaissance aircraft.
aural acquisition Acquisition of target by IR seeker head
as confirmed by pilot’s headset.
aural high-speed warning System triggered by sensed
flight speed, usually presented as EAS, significantly above
autofeathering
allowable maximum. In transport aircraft typically
triggered 10 kt above V mo and 0.01 Mach above M mo . Not
usually made to do more than warn crew.
aural null Condition of silence between large regions
where sound is heard, eg in early radio DF system, in some
types of beacon passage (‘cone of silence’) and several
ground-test procedures.
Aurora Automatic recovery of remotely-piloted
aircraft.
aurora Luminescence in upper atmosphere, esp. in high
latitudes, associated with radiation and/or particles
travelling along Earth’s magnetic field and at least partly
coming from Sun. Exact mechanism not yet elucidated,
but 12 classes identified, based on appearance and
structure.
AUS Airspace Utilisation Section, part of ATC service
(CAA DAP).
AUSA Association of the US Army [office, Arlington,
VA22201] (US).
Ausac Australian Aviation Council [umbrella organization
for aerospace industry].
AUSI Architecture user of system integration.
Ausrire Anglicization of ‘all-union scientific research
institute of radio equipment’ (R).
Austaccs Australian automatic command and control
system.
austenitic steel Ferrous alloys with high proportions of
alloying elements and with microstructure transformed
by heat treatment to consist mainly of solid solution of
austenite (iron carbide in iron, face-centred). Used to
make highly stressed aerospace parts, such as turbine
discs.
AuTC Autothrottle control.
AUTEC Atlantic Undersea Test and Evaluation Center
(USN with UK help, in British territory).
AUTH, Auth Authorized, or authority.
authority 1 Organisation empowered to pronounce
hardware properly designed, constructed and maintained,
and to issue appropriate certificates.
2 Extent to which functioning system is permitted to
control itself and associated systems. Greater * demands
greater inherent or acquired reliability, typical means of
acquiring reliability being to increase redundancy and
provide alternative control channels or in some other way
provide for failure-survival.
Authorization Act of Congress establishing a Federal
agency or procedure (US).
authorised medical examiner Doctor approved by
national licensing authority to issue/renew/refuse aircrew
medical certificates.
Auto-Acas Automatic air-collision avoidance system.
Autob Automatic observation and reporting of weather.
Autocarp, Auto-CARP Automatic computed air release
point.
autoclave Pressure chamber which can be heated; oven
which can be pressurized. Large * can accept major structural
parts of aircraft for adhesive bonding operations.
auto coarse pitch System used on a few multi-piston
engine aircraft to minimise drag after engine failure.
Autodin Automatic digital network (USAF).
autodyne oscillator Multi-electrode valve or transisor
stage of superheterodyne receiver serving as both local
oscillator and amplifier or detector (demodulator).
autofeathering System for automatically and swiftly
75