Engineering Wonders of the World
Volume III

FLYING MACHINES OF TO-DAY. 19 standing that the downward flexing of one end of a deck will make that end rise and lose speed, and that the flattening of the other end will diminish “ lift ” and increase speed. While counteracting a tilt the drag put on one side slews the machine on its vertical axis, and this has to be counteracted by a simulta- neous moving of the steering rudders in the proper direction. Again, the rounding of a curve with the assistance of the rudder alone would produce an extra lift at the outside end, where the speed is greatest; and here the ability to flex the inside end downwards comes How the Machine is started. carriage attached to the under-side of the body- are found a couple of long wooden runners or skates, which prove extremely efficient for absorbing the shocks of landing. Prepara- tory to a flight the machine is placed on a wooden trolley having two small wheels tandem, running on a rail about 23 yards long. Behind the machine, and in line with the rail, is a wooden tower, inside which are a number of iron discs weighing about 1,500 lbs. From the discs a rope passes over a pulley in the tower top, down the tower, A WRIGHT AEROPLANE ON THE STARTING-RAIL; In the rear is the tower with weight discs raised. To the right of the machine is the carriage on which it is moved to the starting- rail after a descent. {Photo, Topical.} in useful. Primarily, the flexure is for the purpose of stability ; incidentally, it assists steering. The four-cylinder engine, which is described in another place, transmits its power to twin- screw propellers behind the decks through Engine and Propellers. chains, one crossed so that the propellers shall revolve in op- posite directions. The indirect drive is taken advantage of to use large pro- pellers turning at little more than a quarter of the speed of the engine. Two screws, work- ing in opposite directions, assist stability by eliminating all gyroscopic action. The Wrights still adhere to their original system of starting their machine by means of external help. In place of the usual wheeled under a pulley at the base, along the ground to a pulley at the far end of the rail, and back towards the carriage, to which it can be attached when the discs have been hoisted to the summit of the tower. To make a start, the pilot sets the engine going at full speed, and releases a catch which had previously prevented the carriage from moving. The machine darts forward, and in a few yards has attained sufficient speed to lift it from the rail, against which, however, it is kept by depressing the elevators. On reaching the end of the rail it is shot from the carriage, and, the elevators being now quickly raised, rises into the air. Against the wind the ma- chine can be started along the rail by the propellers without the aid of the weights.