The Mellette County pioneer. [volume] (Wood, Mellette County, S.D.) 19??-1971, 1923-12-28
RddiOphOne Link Connects
Pilot and Air Field
During $50 Mile Flight

ture OF airships, and TO report to the
noXt field anticipated weather con-
ditions before the pilot took off for
the next stop, became apparent. Fur
Their direction finding experiments
were carried on until March, 1920,
when on an experimental fight, Pilot
Wesley l.. Smith flew between Col
lege Park, Md, and Philadelphia
without regard TO the compass or
land, but relying entirely on the radio
directions, flew directly TO the towers
of the Philadelphia radio station.
However, this method OF directing
planes was abandoned.
When 1t was intended, 10 extend the
Air Mail route from Chicago to San
Francisco in the fall Of 1920, and
establish the first transcontinental
airmail route, it was decided to es-
tablish a radio service between all
airfields, because of the shortcomings
and difficulties Of obtaining n leased
telegraph wire from the West to the
East coast. Hence, in August of that
year, six sets Of radio telegraph work
were installed at the Reno and Elko,
Nevada, salt Lake City, Rock Springs,
Cheyenne and North Platte fields.
Later the sets were also placed at
Omaha. Iowa City, haywood, st.
Louis, Bryan and Bellefonte, New
York and at headquarters in Wash
ington.
This radio circuit, which must be
maintained to a degree. Of efficiency
equal to the telegraph is Of primary
importance in the dispatching of mail
by airplane today. 1t is used to es-
tabliSh communication between fields
handling weather reports for plane
ready to depart from II station to an
adjacent station to handle traffic to
and from Division headquarters, and
Washington and the fields. In addi-
ton TO handling airmail work, some
tinfeS messages for other government
activities are sent. Division head
quarters are located at Salt Lake
City, Omaha, and Hampstead, l.. /.
A watch Of fifteen minutes is stood
each hour ut every station on the air
circuit. Hundreds of important com
munications are handled daily through
these Airmail stations.
As the Airmail service progressed,
q suitable airplane receiver and
transmitted was needed. In Novem-
Der, 1929 were begun the tests which
so successfully eliminated in the
demonstration held at the Omaha
field nearly a year later between a
plane and the ground.
The problem of communication be-
tween plane and ground is a very pc
Culiar me. Due to the fact that Il
comparatively small aerial, and a ra-
do set Of limited power only can be
used on board plane, the range Of the
set is necessarily limited. However,
a delicate receiving set on the ground
will make up for transmitter def
ciencies in the plane.
To reach the speeding plane from
the ground has been the big prob
lem to solve. Bue to the noise Of the
engine, the receiving interference due
to the ignition system Of the engine,
to the small a~ntenna, and TO the limi-
tations Of the equipment in the plane,
the accomplishment Is no small one
Through the foresightedness and
vision of three OF four men, this
problem will have been solved. Paul
Henderson, second assistant post
master general, and G. Egge, Super
intendent of the u. S. Airmail, to-
gether with f. b. Mallory, Radio Elk
pert all had their share in the ac-
complishment.
1t was the vision Of those men, and
the cooperation and willingness Of
such others as Jack Knight, airmail
pilot, ID. Il. Colyer, Western Division
superintendent, Lang, airmail pilot,
r. l.. Davis, radio engineer, {. Hem
pei, Omaha airfield radio supervisor,
that the tests that were held this
week were so successful.
The one thousand watt radiophone
transmitter, which was specially de-
signed and built for the Post Office
Department airmail experiments has
been installed ut the Omaha air field.
Thus this division headquarters pos
sesses the distinction Of having the
only radiophone equipment in the air
mail service today. i.
The range of this transmitter is es-
timated at about 300 to 500 miles
daylight. and up to 1000 miles at
night. BY means Of this set, it is
possible for superintendent at the
fields to talk to any Of their pilots
while the plane is in flight between
fields, as these are less than 500
miles apart. In addition to that,
eventually the fields will oil be equip
ped with %radiOphone sets, so that il
will be possible to have a radio cir
cult link Of radio telephony equal to
the present telegraph system.