the Aviation Dictionary

aerostat - A device such as a balloon or dirigible that is
supported in the air by displacing more than its weight.
aerostatics - The branch of science that deals with the
generation of lift by the displacement of air by a body
lighter than the air it displaces. Balloons and dirigibles
that are filled with hot air or gas fall under the science
of aerostatics.
affective domain - A grouping of learning levels
associated with a person's attitudes, personal beliefs,
and values, which range from receiving through
responding, valuing, and organization to
characterization.
affirmative - In communications, this indicates: Yes.
aerostat air carrier
AGL altitude - The vertical elevation above ground.
Expressed in feet.
agonic line - An irregular imaginary line across the
surface of the earth along which the magnetic and
geographic poles are in line, and where there is no
variation error.
agricultural aircraft - Aircraft that are specifically
designed and built for use in the application of
chemicals to crops for insect and weed control.
aileron - A primary control surface located near the
wing tip that makes up part of the total wing area.
Ailerons are operated by the lateral motion of the
controls and cause rotation of the aircraft about the
longitudinal axis.
aileron angle - The angle of displacement of an aileron
from its neutral, or trailing, position.
aft - To the rear, back, dorsal, or tail of the aircraft.
aft flap - The rear section of a triple-slotted, segmented
wing flap.
- -
aileron spar - A spar that extends only part of the span
after bottom center (ABC)- In a reciprocating engine,
of the wing and provides a hinge attachment point for
the amount of crankshaft rotation after the piston has
the aileron. Also referred to as "false spar."
passed the bottom of its stroke. Expressed in degrees. -
aileron station - Distances measured outboard from the
after top center (ATC)- In a reciprocating engine, the
root end of an aileron, parallel to the aileron spar.
amount of crankshaft rotation after the is ton has
passed the top of its stroke. Expressed in degrees. air - A mixture of gases that comprises the earth's
atmosphere. Pure dry air contains approximately 78%
afterburner - A portion of a jet engine in which
nitrogen and 2 I % oxygen. The remaining 1 % consists
additional fuel is sprayed into the hot, oxygen-rich
of argon, carbon dioxide, hydrogen, and traces of neon
exhaust, where it bums and produces additional thrust.
and helium. Dry air weighs 0.07651 pounds per cubic
Afterburners provide a great amount of additional
foot at sea level with a temperature of 59°F and has a
thrust with a minimum of additional weight.
barometric pressure of 14.69 PSI at 40" latitude.
after-firing - A condition often resulting from either too
air adapters - A component in a centrifugal compressor
rich fuellair mixture or unburned fuel being pumped
gas turbine engine. Its purpose is to deliver air from the
into the exhaust system of a reciprocating engine and
diffuser to the individual can-type combustion
ignited when it comes in contact with some hot
chambers at the proper angle.
component. Sometimes referred to as afterburning or
torching.
air, ambient - The atmospheric air surrounding all sides
of the aircraft or engine. Expressed in units of Ibs./sq.
afterglow - The glow that remains on the
inch or in. Hg.
phosphorescent screen of a cathode ray tube after the
electron beam passes.
air bleed - 1. A small hole in the fuel passage between
the float bowl and the discharge nozzle of a float
aft-fan engine - A turbofan engine that has a fan
carburetor. The hole introduces air into the liquid fuel
constructed as an extension of the turbine blades.
and serves as an aid to atomization. 2. Used in gas
age hardening - The process of increasing the hardness turbine engines for a variety of purposes and is taken
of a metal after the heat-treat process. Age hardening from the engine's compressor section.
occurs at room temperature and continues-for a period
air brake - A plate or series of plates that can be
of several days until the metal reaches its fully
projected into the airplane's slipstream to provide
hardened state.
turbulence and drag to slow the airplane during
aggression - Because of safety concerns or social descent, glide, or when maneuvering. Air brakes differ
structures, students may display the defense from flaps in that they produce no useful lift. Also
mechanism of aggression. --
They may ask irrelevant referred to as speed brakes.
questions, refuse to participate in class activities, or
air capacitor - A capacitor that uses air as the
disrupt the group.
dielectric.
aging - See age hardening.
air carrier - A person who undertakes directly by lease,
agitate - To stir or shake something in order to mix its or other arrangement, to engage in air transportation.
ingredients.
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