The Pleasantville press. (Pleasantville, N.J.) 1912-1929, 1919-02-08
Radio Telephone for AirpIane Use
Developed by Bell Engineers
CONTINUED,

to the matter of equipping airplanes
with wireless telephone apparatus. At
this conference, besides General Squier
and DR.. Jewett, there were present Mr..
Graft, one of DR.. Jewett's principal
assistants; Captain, now Colonel, C. G.
Culver, of the Signal Corps, and Major
Reece, of the British Army Air Service.
This conference discussed the posi-
bility of providing airplanes with wire
less telephone service, and so promising.
were the reports which DR.. Jewett was
able to make with reference to the wire
less telephone system developed by the
Bell engineers that he was ordered in
writing by General Squier to proceed
with the development work on these
systems and to actually equip planes.
AS a result of the work which the
Bell System engineers had already done
they were able in a test at Langley
Field about the first of July, 1917,
actually to demonstrate the working of
the wireless telephone between an air
plane and the ground, and this test
gave results also showing that it was
practical to work the system between
two or more airplanes.
From this time on the work consisted
in obtaining the smallest and lightest
outfit, a convenient form of power plant
to furnish the necessary energy, over
coming the noise made by the airplane
itself, overcoming the inductive inter
ference in the wireless telephone set
arising from the airplane ignition sys-
TEN, designing the best telephone trans
mitter for the peculiar conditions on
the airplanes and other questions of a
similar nature. So complete had been
the fundamental work already accom-
plished, and so rapidly was the work
pushed, that on December 2, 1917, at
the Wright Field, Dayton, Ohio, an
official demonstration was made be-
tween planes, and planes to the ground,
before the Aircraft Production Board
and before officers of the Army and
Navy.
Two planes were sent up into the air,
each equipped with Bell engineers wire
less telephone system. These systems
were so arranged on the planes, which
were two-seaters, that both pilot and
observer received the messages, and the
observer could communicate with the
ground or with the other airplane, and
the pilot and observer could talk to each
other by wire telephone, this being an
important point as the noise in an air
plane is such that pilots and observers
cannot directly communicate with each
other by spoken word. On the ground
there was one of the wireless telephone
outfits. This was equipped with a loud
speaking receiver, so that all of the as
sembled officials could hear both the
orders issued to the airplanes and the
communications from the airplanes.
Orders were issued to each of these
planes from the ground by wireless
telephone and their receipt acknowl-
edged from the planes by the same
means, the orders issued being immedi-
ately executed. The planes also COM
municated with each other. In this
test orders were issued to planes from
the ground over distances as great as
ten miles, a distance at which the planes
were invisible from the telephone sta
ton. The planes communicated with
each other over the same distance, at
which distance, of course, each plane
was entirely invisible from the other.
To appreciate what a tremendous
advance was represented by this appli-
cation of the Bell engineers wireless
telephone system, the best scheme actu-
ally employed at that time must be
known. The best scheme actually en-
ployed did not provide any means Of
communicating between the planes.
Wireless telegraphy was used to send
from the plane to the ground and very
occasionally from the ground to the
plane. In addition to its limitations,
this system required that the observer
in the plane should be able to send
Morse. The practical utility of this
scheme was limited to reporting the
results of artillery fire and correcting
range and to a limited extent for re-
porting from scout planes.
The demonstration showed so on
clusively the success of the Bell System
and made such a strong impression upon
the officials present that Immediately
thereafter large orders for this appara-
tus were placed by both the Army and
Navy, and since then, from time to time,
further large orders have been placed,
and this apparatus was in actual service
on the fighting front.
Large numbers of the Bell System
wireless outfits have been obtained by
our allies and used by them in the war.