Part 19 (1/2)

=Foot-pound=--A ht of 1 lb raised 1 foot

=Fairing=--Usually ht construction of wood and fabric; and bent round detriive it a ”fair” or ”stream-like” shape [15]

=Gravity=--Is the force of the Earth's attraction upon a body It decreases with increase of distance froht”

=Gravity, Specific=--

Density of substance -------------------- Density of water

Thus, if the density of water is 10 lb per unit volu 7 lb, would be said to have a specific gravity of 7/10, _ie_, 07

=Gap= (_of an aeroplane_)--The distance between the upper and lower surfaces of a biplane In a triplane or multiplane, the distance between any two of its surfaces [16]

=Gap, Propeller=--The distance, measured in the direction of the thrust, between the spiral courses of the blades

=Girder=--A structure designed to resist bending, and to coth

=Gyroscope=--A heavy circular wheel revolving at high speed, the effect of which is a tendency toforces

=Hangar=--An aeroplane shed

=Head-resistance=--Drift The resistance of the air to the passage of a body

=Helicopter=--An air-screw revolving about a vertical axis, the direction of its thrust being opposed to gravity

=Horizontal Equivalent=--The plan view of a body whatever its attitude ain or lose momentum

=Inclino the attitude of a body relative to the horizontal

=Instability=--An inherent tendency of a body, which, if the body is disturbed, causes it to move into a position as far as possible away from its first position

=Instability, Neutral=--An inherent tendency of a body to reiven it by the force of a disturbance, with no tendency to move farther or to return to its first position

=Inertia=--The inherent resistance to displacement of a body as distinct from resistance the result of an external force

=Joy-Stick=--See ”Control Lever”

=Keel-Surface=--Everything to be seen when viewing an aeroplane fro strut; in an aeroplane, usually passing through a surface and attached to the main spar, and from the end or ends of which wires are taken to spar, surface, or other part of the construction in order to prevent distortion When used in connection with a controlling surface, it usually performs the additional function of a lever, control cables connecting its ends with the pilot's control lever [17]

=Lift=--The vertical co through the air a surface inclined upwards and towards its direction of ain in a given tiiven altitude