352 



THE NATIONAL GEOGRAPHIC MAGAZINE 



would tremendously facilitate rapid com- 

 munication from one part of the country 

 to another. 



IT COSTS S6o AN HOUR TO OPERATE) AN 

 AIRPLANE TODAY 



The cost of operation of airplanes is 

 very great, the average at this time being 

 about S6o an hour, and is about 20 to 50 

 per cent more for seaplanes. In fact, 

 seaplanes, or flying-boats, are the most 

 expensive aircraft to operate. 



Of course, seaplanes have the advan- 

 tage of being able to land in many places 

 not provided with airdromes. This is 

 particularly so in Canada, where a very 

 great percentage of the surface of the 

 country is covered with water and lakes. 

 In fact, seaplanes can fly all over Canada 

 and almost always have a landing place 

 within gliding distance. On the other 

 hand, seaplanes are worthless in the 

 winter time, when the lakes and rivers 

 are frozen or have floating ice on them. 



It is estimated that carrying passengers 

 costs almost 70 cents per mile. 



The great advantage about airplanes is 

 their speed ; and it has been found that 

 the higher one is able to get, the greater 

 the speed that can be obtained, on account 

 of the lessened resistance of the air. At 

 30,000 feet, speeds of over 200 miles an 

 hour have been obtained, with ordinary 

 equipment, merely adapted for that pur- 

 pose and not constructed specifically 

 for it. 



The way that these high altitudes are 

 obtained is by the use of a turbo-booster 

 in connection with the gasoline engine. 

 The turbo-booster is a turbine which is 

 actuated by the exhaust from the engine, 

 this in turn works an air compressor, or 

 air pump, that delivers compressed air 



to the carbureter of the engine, thereby 

 keeping up a proper mixture, which 

 otherwise would be lost on account of 

 the rarefaction of the air at high altitudes. 

 By the use of this device greater alti- 

 tudes will be obtained and the power 

 of an engine kept up in a remarkable 

 manner. For instance, by using the 

 turbo-booster with a 400 horse-power 

 engine, this engine will deliver as great 

 horse-power at 30,000 feet as a 1,000 

 horse-power engine would without the 

 turbo-booster. 



SPEEDS OP 3OO TO 4OO MITES PER HOUR 

 ARE POSSIBLE 



We believe that, with the development 

 of equipment of this kind and the con- 

 struction of special airplanes to be used 

 at very high altitudes, speeds of 300 

 miles an hour and over can be obtained. 



At these altitudes, also, there are regu- 

 lar winds blowing, similar, in a way, to 

 the trade winds, some of which have a 

 speed of over 100 miles an hour; so that, 

 by combining the speed of our airplanes 

 with the speed of the wind, we will get 

 velocities of from 300 to 400 miles an 

 hour in many cases. This will enable very 

 rapid communication between America 

 and Europe, San Francisco and New 

 York, or other places of corresponding 

 distances. This class of transportation 

 we believe is not very far away. 



The United States has the best climate, 

 all the natural resources for the construc- 

 tion of airplanes, the manufacturing 

 ability, the engineering ability, and its 

 men make the best pilots in the world. 



From the standpoint of national de- 

 fense, we can get greater security, dollar 

 for dollar, from an air force than we can 

 from any other military element. 



Notice of change of address of your Geographic Magazine should be re- 

 ceived in the office of the National Geographic Society by the first of the month to 

 affect the following month's issue. For instance, if you desire the address changed 

 J or your May number, the Society should be notified of your new address not later 

 than April first. 



