New-York tribune., 1908-08-12
EDISON AND THE HELTCOPTER.

Not having given any special thought TO
aeronautic problems for fifteen years, and hav-
ing considered them only casually at any time,
the inventor of the incandescent electric lamp
is hardly to be regarded as an authority on
airships While Mr.. Farman was visiting him
the other day, Mr., Edison paid him the graceful
compliment of disparaging the rival of the
type of vehicle with which his guest won the
Deutsch prize last December. 1t is to he OBJ
served however that the West Orange oracle
is little better pleased with the aeropane than
with the dirgible balloon. Machines like Mr.
Farman's cannot hover over a given spot says
Mr. Edison, and hence are to be condemned
He prefers still another style of airshp-the
helcopter-which can. according to its ad-
vocates. remain motioness enough to furnish
an admirable target for sharpshooters
The chief difference between the balloon de-
vised by Montgolfer and the one with which
Major Renard experimental thirty-odd years
ago is that the former is fitted only for ascent,
while the latter is equipped also with the
means of making horizontal progress. In out
ward form and in the principle by which buoy
ancy is maintained the aeroplane is very unlike
the dirigible balloon, but they both have ma
chinery for propulsion. Whether they are en-
ployed for sport exploration or military service,
the ability to travel in a path almost or quite
parallel with the earth's surface is deemed es-
sential. 1t is equally so in any other airshlp
which is to be put TO the same uses. In the
belicopter a screw or a pair OF screws Is so
placed that rotation exercises a direct lifting
power Ascent is thus effected much more
quickly than with an aeroplane. which rises
gradually: but once up something else is requi-
site Forward motion would be secured by
some inventors who have experimented with
the helicopter by shifting the shafts on which
the screws are mounted from a vertical to
horizontal position. Others propose to use sep
arate shafts for the two classes of work. SO
little has been done with either plan in actual
practice however, that the feasibility or the
kind of flying machine favored by Mr.. Edison
and the nature and number of its drawbacks
can hardly be estimated as yet.
question which the designer of the yet
imperfectly developed helicopter must answer
to himself is, How shall an airship of that sort
he kent from falling when it once reaches any
desired altitude and a forward motion begins!
If reliance is placed on the lifting screws alone.
operated at diminished speed, something must
he done to insure steadiness in fight, like sup
plying side planes. If the lifting screws are
called into play for ascent only, large stretches
of horizontal surface would be needed for the
sake of buoyancy Indeed. more than one
aeronautc inventor has proposed to adopt as
his general model the aeroplane, and then to
add an extra set of screws to help him to rise.
In the course of his conversation with his
guest on Monday. Mr.. Edison mentioned an
idea of his own which he never followed up,
but which may have merit. He employed
novel method of persuading a parachute to
open How well it worked he did not say, but
something better than the ordinary parachute
is certainly needed No kind of travel on lana
or by water, is beset with perils as great as
those of an aerial voyage. For whatever pur-
NTr To or1'S
and Count Zeppeins is undertaken, they should
be equipped with aerial life preservers which
will work infallby when most wanted. mas
much as Mr.. Edison did not find it convenient
or practicable to perfect his device some one
else should turn his attention to the problem.