Part 19 (2/2)

=Lift-Drift Ratio=--The proportion of lift to drift

=Loading=--The weight carried by an aerofoil Usually expressed in pounds per square foot of superficial area

=Longeron=--The terth-ways of a fuselage [18]

=Mass=--The mass of a body is a measure of the quantity of material in it

=Momentum=--The product of the mass and velocity of a body is known as ”momentu surface consists of one surface or one pair of wings

=Multiplane=--An aeroplane of which thesurface consists of nus e strut

=Nacelle=--That part of an aeroplane containing the engine and/or pilot and passenger, and to which the tail-plane is not fixed [19]

=Neutral Lift Line=--A line taken through a surface in a forward direction relative to its direction of e If the attitude of the surface is such as to make the said line coincident with the direction ofsolely of drift The position of the neutral lift line, _ie_, the angle it makes with the chord, varies with differences of camber, and it is found by means of wind-tunnel research

=Newton's Laws of Motion=--1 If a body be at rest, it will remain at rest; or, if in ht line until acted upon by soe of the quantity of motion (momentum) is proportional to the force which causes it, and takes place in the direction of the straight line in which the force acts If a body be acted upon by several forces, it will obey each as though the others did not exist, and this whether the body be at rest or in motion

3 To every action there is opposed an equal and opposite reaction

=Ornithopter (or Orthopter)=--A flapping wing design of aircraft intended to ier=--This ter the main surface with an elevator placed in advance of it So the tail-plane with thesurface [20]

=Pancake, to=--To ”stall”

=Plane=--This ter surface Such application is not quite correct, since ”plane” indicates a flat surface, and the lifting surfaces are always cambered

=Propeller=--See ”Air-Screw”

=Propeller, Tractor=--An air-screwsurface

=Propeller, Pusher=--An air-screwsurface

=Pusher=--An aeroplane of which the propeller issurface

=Pylon=--Any V-shaped construction from the point of which wires are taken

=Power=--Rate of working [21]

=Power, Horse=--One horse-power represents a force sufficient to raise 33,000 lb 1 foot in a ine is a measure of the rate at which work is done by the pressure upon the piston or pistons, as distinct froine does work The latter is usually termed ”brake horse-power,” since it in of=--The available quantity of power above that necessary to le