FLYING MACHINE 



22150 



FLYING MACHINE 



.LYING MACHINE, man's dream through 

 many ages, made a reality in the present cen- 

 tury by the invention of the heavier-than-air 

 device and the development of the balloon 

 from a bubble drifting with the winds to a true 

 airship. 



Faith and Unbelief. It is a matter of record 

 that when Wilbur and Orville Wright, the 

 brothers who in 1903 made the first successful 

 flier, announced to their family their intention 

 to build a heavy machine which would fly in 

 the air, their father took immediate steps to 

 discourage so foolish an idea. He wrote to a 

 professor in a great university, outlining the 

 "crazy proposition" and asking him whether 

 he believed it could be done. This professor 

 in his reply declared a man-made flier to be a 

 physical impossibility, and Mr. Wright handed 

 the letter to his sons with the remark, "I told 

 you so." 



But the sons had faith in their idea, and 

 they continued their experiments patiently and 

 unceasingly, meeting and overcoming, one by 

 one, the innumerable obstacles which blocked 

 their progress. When at last their machine was 

 tried out in the presence of army officers at 

 Fort Myer, Va., when it soared into the air, 

 obedient to the will of the driver and came 

 lightly to earth again at a spot previously 

 designated, they wired their father, "We told 

 you so." 



Why Aeroplanes Fly. The Wright brothers 

 did not discover the principles of flying any 

 more than Watt discovered the power of steam. 

 What they did, like Watt and nearly all other 

 inventors, was to devise a mechanism for util- 

 izing principles already known. 



The basic idea of a flying machine is simple 

 enough it flies for the same reason a kite 

 flies/ When you close a door, the slanting 

 surface of the latch is met by a metal guard, 

 and though the pressure of the guard against 

 the latch is outward, the latch retreats at right 

 angles into' the door. This is because the 

 pressure of the guard acts perpendicularly to 

 the surface of the latch, and (as the article 



COMPOSITION OF FORCES explains) such a pressure 

 has the same effect as would two forces, one 

 merely pressing the latch against the side of 

 its casing and the other moving it inward. 

 In a kite the pressure of the wind corresponds 

 to the pressure of the metal guard upon the 

 latch; the force of gravity corresponds to 

 the resistance of the spring behind the latch; 

 the kite string corresponds roughly to the cas- 

 ing. If the wind is strong its upward thrust 

 (that is, the upward element of the pressure 

 perpendicular to the kite's surface) will over- 

 come the force of gravity; if not, the boy who 

 flies the kite may increase the pressure by 

 running against the wind. 



In an aeroplane there is no restraining string, 

 and the machine can move forward. The 

 effect of so doing is exactly that of the boy 

 running with the kite ; it produces air pressure 



FLYING MACHINES 



(a) A British biplane; (b) an all-steel battle 

 plane; (o) a Bleriot monoplane. 



against the slanting under surface of the ma- 

 chine, and if the engines propel the aeroplane 

 fast enough this pressure overcomes the force 

 of gravity and the machine soars into the air. 



The Pioneers. Not all men of the nineteenth 

 century were like the professor to whom the 

 elder Mr. Wright submitted his question. 

 Those who understood the principle of the kite 

 realized that flying machines could be made 

 if engines could be built capable of driving 

 them at high speed, and if means could be dis- 

 covered to control their equilibrium and the 

 direction of their flight. 



Speed is necessary to an aeroplane because 

 in general the pressure of the air beneath it is 

 proportionate to the square of the velocity, 



