In most aeroplanes, whether of the single or double type, the
propeller, or propellers, are directly connected to the motor. In some
monoplanes the motor, especially the Gnome, itself rotates, carrying
the blades with it. In biplanes, such as the Burgess, Wright or
Curtiss, it is the custom to operate the propellers directly from the
motor, either by means of a shaft, or by sprocket chains.
But, in any case, the starting of the engine means the whirling of the
propellers, for they are directly connected. This is why, when once
the engine stops in mid-air, it can not be started again. Or at least
if it is started it is mostly a matter of chance in getting it to go
under compression or by the spark. There is no chance for the aviator
to get out and whirl the propellers which are, in a measure, what a
flywheel is to an automobile.
Also that is why the aviator has to be in his seat at the controls, and
have some other person start his machine for him, by turning over the
propeller, or propellers until the motor fires.
Lately however, especially since the talk of the flight across the
Atlantic, a means has been found to allow the aviator, or some helper
with him, to start the engine once it has stalled in midair. This is
accomplished by means of a sprocket chain gear and a crank connected to
the engine shaft. The turning handle is within reach of the aviator.
But Mr. Vardon, and Dick, working together, had evolved something
better than this. Of course in their craft, with space to move about
in the cabin, they had an advantage over the ordinary aviator, who, in
case of engine trouble, has no place to step to to make an examination.
But Dick's engine was not directly connected to the propellers. There
was a clutch arrangement, so that the motor could be started, with the
propellers out of gear, and they could be "thrown in," just as an
automobile is started. This gave greater flexibility, and also allowed
for the reversing of the propellers to make a quick stop.
And it was not necessary for Dick to "crank" his motor. An electric
self-starter did this for him, though in case of emergency the engine
could be started by hand.
In fact everything aboard the Abaris was most up-to-date, and it was on
this that Dick counted in winning the big prize.
"Well, I guess everything is as ready as it ever will be," remarked the
young millionaire, as he and the aviator made a final inspection of the
craft. "Get aboa
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