the Aviation Dictionary

E . effective value
E
E-core - The laminated core of an electric transformer
cut in the shape of the letter "E." The coil windings are
mounted on the core.
early warning radar - Long-range radar used to detect
incom ing aircraft or missiles soon enough to be eddy - In meteorology, an organized movement of air in
intercepted by defensive aircraft or missiles.
a circulation of a particular size. The organization is
more obvious in the larger scale circulations.
earplug - A rubber, wax, or soft plastic device worn in
the canal of the ear to keep loud noises from damaging eddy current - A current induced into the core of a coil,
the ear and to help prevent hearing loss.
transformer, or the armature core of a motor or
generator by current flowing in the winding. Eddy
earth connection - An electrical connection with a currents cause power loss and are minimized by
ground. Thc United Kingdom uses "earth" for the laminating the iron cores.
electrical term "ground."
eddy current inspection - A nondestructive inspection
earth ground - In electricity, a ground connected used Lo locate surface or subsurface defecls in a metal
directly to Earth. This connection is usually achieved part. This is a comparison-type inspection, based on the
by attaching a grounding clamp to a metal water pipe difference in conductivity of a sound and a defective
or to a grounding rod driven into Lhe ground. The third
plug in a three-wire system is usually connected to
earth ground.
part.
eddy current losses - The electrical losses in the core of
a transformer or other
Earth induction compass - A direction indicator in an electrical machine. The
aircraft that derives its signal from the lines of flux of induction of eddy currents
the Earth cutting across the windings of the flux valve. into the core robs the
Earth's magnetic field - The magnetic lines of flux that machine of some of its
surround the Earth. These lines enter and exit the Earth power.
at the magnetic north and south poles, close to, but not edge distance - The
aL, the geographic poles.
distance from the center of
easy-out - A screw extractor used to remove broken a bolt or rivet hole to the
screws or studs. It is made of hard steel and has a point edge of the material.
with a tapered, left-hand spiral-like thread. A hole is edge thickness-~he thickness ofthe edge ofa material.
drilled in the shank of the broken screw and the
easy-out is screwed into it by turning it counter- edge-grain wood - Wood that has been sawed from the
clockwise.
tree in such a way that the edges of its grain are visible
in the wide part of the plank. Also referred to as
eccentric - A disk or wheel having
8
its axis of revolution quarter-sawed wood.
displaced from its center
so that it is capable of Edison effect - The emission of electrons from a heated
imparting reciprocating
filament attached to an electrode placed in an
motion.
evacuated tube. The discovery of Thomas A. Edison in
1883.
eccentric cam - A
circular cam with a eductor - A jet pump used in some aircraft hcl systems
displaced axis. As the
to remove fuel from a vent-drain tank and return it to
shaft rotates about its
the main tank.
axis, the outside of the
effect - A principle of learning, which states that
eccentric cam rises and falls, changing rotary motion learning is strengthened when accompanied by a
into reciprocating motion.
pleasant or satisfying feeling, and that learning is
echo - In radar terminology, the energy reflected or weakened when associated with an unpleasant feeling.
scattered a target and lhe radar scope presentation effective pitch - The actual distance a propeller moves
Lhe return Crom a target.
through the air in one revolution. It is the difference
economizer system - A power compensator or a power between the geometric pitch of the propeller and the
enrichment system in a carburetor or fuel injection propeller slip.
system that adds additional fuel. It enriches the fuel thread - The effective (or thread
mixture at high power engine operations. The includes the complete thread and that portion of the
economizer is closed during cruising speeds.
incomplete thread having crests not fully formed.
Aircraft Technical Book Company
P.O. Box 270
Tabernash, CO 80478
http:llw.ACTechbooks.com
effective value - The root mean square (RMS) value of
sine wave AC. It is equivalent to 0.707 times the peak