the Aviation Dictionary

short wave trough . side stick
airworthiness, operations, noise, and pollution be shrink-wrapped is covered with a film of transparent
standards.
thermoplastic material. When heat is applied to the
short wave trough - Troughs in the mid- and upper
film, the film shrinks to encase the part.
troposphere and lower stratosphere that correspond to shroud - A cover or housing used to aid in confining an
de;eliping frontal lows. short wave troughs are air or gas flow to a desired path.
smaller in scale than long waves. They move toward
the east, averaging 600 nautical miles per day.
shorting switch - A multi-pole switch where one circuit
is completed before another circuit is opened.
shot peening - A process used to strengthen metal parts
by blasting its surface with steel shot.
shoulder bolts - A bolt where the threaded portion is
smaller than the shank. It is often used for the
installation of plastic materials to prevent over
tightening.
shoulder-wing airplane - An airplane having one main
supporting wing surface mounted near the top but not
directly on top of the fuselage. Also referred to as the
mid wing.
show - Unless the context otherwise requires, means to
show to the satisfaction of the Administrator.
shower - Precipitation from a cumuliform cloud;
characterized by sudden onset and cessation, rapid
change of intensity, and usually by rapid change in the
appearance of the sky; showery precipitation can be in
the form of rain, ice pellets, or snow.
shroud ring - A stationary sealing ring positioned just
outside the tip plane of rotating airfoils. Sometimes it is
the inner part of an outer casing.
shrouded-tip turbine blade - A blade with tip
platforms that fit one to another to form a circular
support ring. Often, the shrouds have thin abradable
rims attached at their outer edge to act as air seals.
shunt - An accurately calibrated resistor placed in
parallel with a meter movement for measuring current.
Current flows through the shunt and produces a voltage
drop proportional to the amount of current. The
ammeter movement measures this voltage drop and
displays it in amperes.
shunt circuit - A circuit that has several paths for
electrons to flow.
shunt ohmmeter - An ohmmeter circuit used for
measuring low resistances. The unknown resistor is
placed in parallel (shunt) with the meter and resistance
is measured by the amount of current the unknown
resistor takes from the meter.
shunt-wound generator - A generator in which the
field and armature are connected in parallel.
shower of sparks - The induction-vibrator-type starting
system used in some Bendix magnetos. A vibrator shunt-wound motor - A motor in which
directs pulsating direct current into the primary circuit electromagnetic field windings are connected in
of one of the magnetos when the points are closed. parallel with the armature.
When the retard points open, pulsating current flows to
shut-off valve -A flow-control valve used to shut off or
ground through the primary coil and induces a high
stop a flow of fluid.
voltage into the secondary winding. As long as both
sets of points remain open, a shower of sparks occurs at shuttle valve - A valve, mounted on critical
the spark plug.
components, that directs system pressure into the
show-type finish - A glass-like aircraft finish achieved
actuator for normal operation but switches to
emergency fluid when the emergency system is
by applying many coats of dope and repeated sanding
actuated.
and polishing. -
shrink fit - Interference fit between parts when the
female part is heated and the male part is chilled before
they are assembled. When they reach the same
temperature, they are essentially locked together.
shrinking - The act of compressing a material into a
smaller volume or area.
shrinking block - A sheet
metal forming tool that
clamps metal to prevent it
from buckling while hammering
its edge to shrink
it.
shrink-wrap - A method used to protect products from
dirt and dust while they are held in storage. The part to
Aircraft Technical Book Company
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http://w.ACTechbooks.com
side bands - The frequency bands on each side of a
carrier frequency produced by modulation.
sideslip - An uncoordinated flight condition in which
the aircraft moves downward and toward the inside of
the turn. Sideslip can also result from the use of rudder
to maintain heading in an engine-out situation.
sidestep maneuver - A visual maneuver accomplished
by a pilot at the completion of an instrument approach.
It permits a straight-in landing on a parallel runway,
which must not be more than 1200 feet to either side of
the approach runway.
side stick - A primary flight control input located to the
side of the pilot.