is
concerned, it will, to say the least of it, earn unpopularity with
senior officers, and fail to develop respect and good work where men
are concerned.

THE AEROPLANE SHED.--This should be kept as clean and orderly as
possible. A clean, smart shed produces briskness, energy, and pride of
work. A dirty, disorderly shed nearly always produces slackness and poor
quality of work, lost tools, and mislaid material.

[Illustration]

[Illustration]

GLOSSARY

_The numbers at the right-hand side of the page indicate the parts
numbered in the preceding diagrams._

=Aeronautics=--The science of aerial navigation.

=Aerofoil=--A rigid structure, of large superficial area relative to
its thickness, designed to obtain, when driven through the air at an
angle inclined to the direction of motion, a reaction from the air
approximately at right angles to its surface. Always cambered when
intended to secure a reaction in one direction only. As the term
"aerofoil" is hardly ever used in practical aeronautics, I have,
throughout this book, used the term SURFACE, which, while academically
incorrect, since it does not indicate thickness, is the term usually
used to describe the cambered lifting surfaces, _i.e._, the "planes"
or "wings," and the stabilizers and the controlling aerofoils.

=Aerodrome=--The name usually applied to a ground used for the practice
of aviation. It really means "flying machine," but is never used in that
sense nowadays.

=Aeroplane=--A power-driven aerofoil fitted with stabilizing and
controlling surfaces.

=Acceleration=--The rate of change of velocity.

=Angle of Incidence=--The angle at which the "neutral lift line" of
a surface attacks the air.

=Angle of Incidence, Rigger's=--The angle the chord of a surface makes
with a line parallel to the axis of the propeller.

=Angle of Incidence, Maximum=--The greatest angle of incidence at which,
for a given power, surface (including detrimental surface), and weight,
horizontal flight can be maintained.

=Angle of Incidence, Minimum=--The smallest angle of incidence at which,
for a given power, surface (including detrimental surface), and weight,
horizontal flight can be maintained.

=Angle of Incidence, Best Climbing=--That angle of incidence at which an
aeroplane ascends quickest. An angle approximately halfway between the
maximum and optimum angles.

=Angle of Incidence, Optimum=--The angle of incidence at which the
lift-drift ratio is