Applied Science 80S 



January 62.5 per cent. ; February 76 per cent. ; March 95.4 per 

 cent.; April 94.8 per cent.; May 94.7 per cent.; June 91 per 

 cent. ; July 93.8 per cent. ; August 94,8 per cent. ; and September 

 93 per cent. These figures do not appear too bad, particularly 

 when it is borne in mind that on several occasions when the 

 weather was too rough for the cross-Channel steamers to make 

 the trip, aircraft flew safely between the two capitals. 



The Future 



Aircraft fifty years hence will probably be very different 

 machines from those employed at the present day. Possibly heli- 

 copters, machines which can rise and land vertically, hover and 

 attain horizontal flight, will have been sufficiently developed to 

 make it possible to bring air traffic into the hearts of cities, land- 

 ing on roofs or in other confined areas. The present idea of a 

 helicopter is to have a body for the carriage of pilot and pas- 

 sengers attached to two or more air-screws revolving horizontally 

 in opposite directions, so that the machine may arise and descend 

 vertically. This, however, is of little use in itself, and it must 

 be so perfected that in addition to vertical flight, horizontal 

 flight both forwards and sideways can be achieved. Many prob- 

 lems confront the designer, but these will be overcome in course 

 of time. 



Height indicators, showing the pilot the actual height above 

 ground at all times will minimise the danger of flying in fog, 

 whilst automatic landing apparatus and air brakes will still fur- 

 ther ensure the safety of the airways. Engines of greater horse- 

 power and different types, perhaps developments of the steam 

 turbine or possibly electric motors to which power is transmitted 

 by wireless from ground stations, will come into use. Silent air- 

 screws, noiseless engines, and reduction of vibration will add to 

 the comfort of passengers. Self-starters will minimise the work 

 of starting up. Speed will develop enormously until the ordinary 

 passenger-going machines will fly at hundreds of miles an hour. 



