Evening star., 1936-09-13

anu AAA GA AAAO SAAPAoyhAShes 4AASAC ~
continue during the remainder Of the
year, and that the second half of
1886 will show further new recores
in every department of air trans
portation.
More than 5000 persons now are
given full-time employment by the
air transport companies of the United
States, the Federal report shows. At
the end of the six-month period the
air lines had 422 airplanes in service
and employed 692 pilots, 432 CO.
pilots, 2,714 mechanics and riggers,
1885 other hangar and field per-
sonnel, 264 hostesses. Al stewards and
1892 Office workers, or q total of
9,o70 persons
American air lines during the six
months carried 483,7l2 passengers,
3,548,O75 pounds of express and 8,297,-
885 pounds of airmail. They flew
total of 33,523,075 miles. or 204, sol ,624
passenger miles. In doing so they
used l7.OO8,034 gallons of gasoline
and 405,977 gallons of oil.
These figures cover both domestic
air lines and those operated under
the United States flag to foreign
countries. On the domestic lines only,
miles flown totaled 29,078.403, pass
engers carried, 42l ,5l9; express, 2,9l1.-
IT'S pounds, and mail, 100000
pounds.
The domestic airlines had 49,19i
flights scheduled during the six
months. OF this total, 45,676 were
started. There were 2,066 extra sec
tions flown to accommodate demands
for additional space. The total num-
ber of trips completed was 45,l50. OF
all trips scheduled, plus extra sections,
$500 per cent were completed OF
trips started, s4.57 per cent we're COM
pleted.
The average speed for all the domes-
tic airlines was l475 miles per hour
and the average length Of the in
dividual passengers trip was 1853
miles. Passengers actually occupied
1898 per cent of all the seats avail
able
Between a number of the major cit
les in the United States it is estimated
unofflcially by airline operators that
at least 10 per cent of all passenger
travel now is handled by air and that
for the country as a whole. alrlines
have captured about per cert of all
railroad Pullman passengers.
The Post Office Department has re-
ported that for the fiscal year which
ended last June 80 airmail poundage
totaled more than 100000 pounds
for the first time in history. During
the current fiscal year it is anticipated
the mail poundage will pass the TO-
900, ,000-pound mark.
During the six months, the domestic
airlines received S5,979,644 in airmail
payments from the Post Office De-
partment. Passenger fares, averaging
approximately 5l2 cents per mile, on a
basis of 9,503. .354 passenger miles
flown, brought in only trif1e less than
100000 900, it is estimated.
TESTIFYING to an encouraging in
crease in aviation activity. the
aircraft manufacturing industry In the
United States during the first half of
1886 produced more airplanes than
during the entire year 1888. accord
ing to figures of the Bureau of Air
Commerce.
The industry during the first six
months Of this year turned out 1853
aircraft, as compared with 851 during
the first half of 1885 and with 1924
during the whole of 1888.
In the light plane classification,
production increased from 393 in the
first half of 1885 to 622 in the first
half of 1886, continuing an upward
trend which became noticeable dur
ing 1885.
The total of 1853 aircraft in
cluded 764 domestic civil aircraft, 407
airplanes for military delivery and
1872 constructed for expectation. OF
those built for domestic civil use,
656 were monoplanes and 108 BIZ
planes. Among the monoplanes, cabin
types led over open-cockpit airplanes
by GIT to 80. Cabin planes also were
most numerous among the biplanes,
96 to II with open cockpits.
THE automatic pilots with which
most of the modern airliners now
being produced are equipped are ri
vailed in mechanical intelligence"
only by special apparatus designed
to test the accuracy Of the pilot itself.
The automatic testing device, now
a part of the shop equipment of the
large air transport lines, is used to
check the accuracy of the automatic
pilots before installation and after
ing machine proves to be the most in
teresting of all the sights witnessed by
visitors at the big Transcontinenta
& Western air base at Kansas City,
according to officials of the line.
The testing machine is equipped
with all of the parts used in the auto
matte pilot installations, so arranged,
however, as to subject the automatic
pilot to conditions much more severe
than those encountered in actual
flight. The testing is done by vacuum
and pressure.
The horoscopes within the control
unit are driven by air drawn into q
vacuum chamber from which the air
is evacuated by motor driven pump
to the pressure equivalent of five
inches of mercury. The unit which
applies movement to the controls of
the air plane is actuated by an oil
pressure of 125 pounds per square
inch, also furnished by a motor driven
oil pump.
After an automatic pilot assembly is
overhauled in the T. w. A. instrument
department. it was explained, it is
given a two-hour test in the checking
machine, which can be adjusted to go
through all of the motions of yaw,
pitch and turn. The instrument being
tested records through the testing
machine its efforts to counteract these
forces.
The automatic pilot, it was ex-
planned, can be adjusted to a sensi-
tivity 10 times that of the human
tnlIch in detectin6 the sl;obtaef v,ovs-