Online Book Reader

Home Category

The Aeroplane Speaks [53]

By Root 411 0
flying speed.

Dope, to--To paint a fabric with a special fluid for the purpose of tightening and protecting it.

Density--Mass of unit volume, for instance, pounds per cubic foot.

Efficiency--Output Input

Efficiency (of an aeroplane as distinct from engine and propeller)-- Lift and Velocity Thrust (= aeroplane drift)

Efficiency, Engine--Brake horse-power Indicated horse-power

Efficiency, Propeller-- Thrust horse-power Horse-power received from engine (= propeller drift)

NOTE.--The above terms can, of course, be expressed in foot- pounds. It is then only necessary to divide the upper term by the lower one to find the measure of efficiency.

Elevator--A controlling surface, usually hinged to the rear of the tail- plane, the operation of which turns an aeroplane about an axis which is transverse to the direction of normal horizontal flight.

Empennage--See ``Tail-plane.''

Energy--Stored work. For instance, a given weight of coal or petroleum stores a given quantity of energy which may be expressed in foot-pounds.

Extension--That part of the upper surface extending beyond the span of the lower surface.

Edge, Leading--The front edge of a surface relative to its normal direction of motion.

Edge, Trailing--The rear edge of a surface relative to its normal direction of motion.

Factor of Safety--Usually taken to mean the result found by dividing the stress at which a body will collapse by the maximum stress it will be called upon to bear.

Fineness (of stream-line)--The proportion of length to maximum width.

Flying Position--A special position in which an aeroplane must be placed when rigging it or making adjustments. It varies with different types of aeroplanes. Would be more correctly described as ``rigging position.''

Fuselage--That part of an aeroplane containing the pilot, and to which is fixed the tail-plane.

Fin--Additional keel-surface, usually mounted at the rear of an aeroplane.

Flange (of a rib)--That horizontal part of a rib which prevents it from bending sideways.

Flight--The sustenance of a body heavier than air by means of its action upon the air.

Foot-pound--A measure of work representing the weight of 1 lb. raised 1 foot.

Fairing--Usually made of thin sheet aluminum, wood, or a light construction of wood and fabric; and bent round detrimental surface in order to give it a ``fair'' or ``stream-like'' shape.

Gravity--Is the force of the Earth's attraction upon a body. It decreases with increase of distance from the Earth. See ``Weight.''

Gravity, Specific--Density of substance Density of water. Thus, if the density of water is 10 lb. per unit volume, the same unit volume of petrol, if weighing 7 lb., would be said to have a specific gravity of 7/10, i.e., 0.7.

Gap (of an aeroplane)--The distance between the upper and lower surfaces of a biplane. In a triplane or multiplane, the distance between a surface and the one first above it.

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 combine lightness and strength.

Gyroscope--A heavy circular wheel revolving at high speed, the effect of which is a tendency to maintain its plane of rotation against disturbing forces.

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 may be.

Impulse--A force causing a body to gain or lose momentum.

Inclinometer--A curved form of spirit-level used for indicating 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.
Return Main Page Previous Page Next Page

®Online Book Reader