Evening star., 1935-09-01

trict, or "a in all, are five years old
or older and the age Of three others
could not be determined, but also are
probably more than five years old.
The only multi-engined airplane pri-
vately owned here was built In 1881.
OF the newer models owned by WASH
ington people, IL were built in 1881,
8 in 1882, 8 In 1888 and rs in 1884.
Twenty-nine of the airplanes owned
by Washtngtonians are of the light
airplane" class, Weighing under 1000
pounds. Five Of these, all mono
planes. are within the gross weight
limit of 1000 pounds. In the weight
range from 1000 to 1000 pounds
there are Is monoplanes and IL BIZ
planes. Only Of the 90 airplanes
are in the weight class Of more than
5000 pounds.
All but Of the District-owned
airplanes are licensed by the De-
partment of Commerce and the other
bear Department Of Commerce
registration numbers, but are not
licensed.
lac 4OCdl uI CO AIC RnIb VI u uA~
tional survey made by the Commerce
Department as Of June /, last. The
survey shows that in the United States
on that date there were 8.733 civilian
airplanes. OF the total approximately
one-half were produced prior TO 1880
and were still in service on June ].
Further speeding up Of air transport
schedules between the Atlantic and
Pacific coasts will result from q
100000 improvement and con-
version program just put into effect
by United Air Lines. Fifty-five twin
engtned Boeing transport airplaneS
are to be converted to operate at
maximum speeds of 202 miles per hour
and cruising speeds of 1S9 miles per
hour. 1t was announced in Washington
by F. P. OToole, local trafiic repre-
sentative of the line.
The expenditure, said TO be the
largest made In the air transport
field this year, covers purchase Of l30
supercharged 550-horsepower engines
with contEollable pitch propellers. The
new geared engines are expected to
| increase the speed of the big airliners
| about 19 miles per hour and to permit
quieter and more efficient operation.
1t is said that the ships will be able
to climb, fully loaded, to IL 900 feet
on either one Of their two engines.
Smoke from industrial communities
is a source Of considerable hazard TO
aviation and is retarding the develop
ment Of private flying In many parts
Of the country, according to q report
by H. B. Meller and L. B. Sisson Of
the Mellon Institute of Industrial Re-
search, University Of Pittsburgh. The
report is based on q thorough study
in which they had the cooperation Of
specialists in meteorology, aviation
engineering and commercial aviation.
1t has been found that not only
does smoke in itself constitute an
obstacle to safe flying but that the
presence of large quantities Of smoke
and gases in the air increases the
prevalence of fog and that fogs Into
which smoke is thoroughly mixed will
last for hours or even days longer
than might have been the case with
fog alone. Smog-the mixture Of
smoke and fog-may build up, as has
been noted at Pittsburgh and else
where, to height of several thousand
feet and resist penetration by SUM-
light for two or three days at time.
There may be almost unlimited
visibility above the pail Of smoke and
fog but down below there Is a blanket
which the aviator can pierce in safety
only by the use of instrument approach
and blind landing equipment.
"Various pilots who have been
actively flying a route between WASH
ington and Detroit, via Pittsburgh
and Cleveland" 1t is stated In the
report, "are of the unanimous opinion
that factory and city smoke they en-
counter on the route constitutes
somewhat of a hazard to the pri.
vate flyer who is not equipped with
two-way radio, and therefore can
not make his position known and
that, with the predicted influx Of
the private plane owner, uncontrolled
smoke will naturally constitute a
much greater hazard to the regularly
operating airlines'
Smoke in dense form and cover
ing large area occasionally has ex-
tended from Pittsburgh to Washing
ton, necessitating considerable detour
for planes not equipped with instru-
ments for blind flying"
Possible solutions Of the smoke
problem lie In the selection Of land
ing fields to the windward Of smoke
producing regions, the growing use
of better equipment for the burning
of soft coal and Oil in industrial
plants, and the increasing use Of such
SmokeleSS fuels as anthracite, coke
and gas in smaller commercial places
and in dwellings, it was pointed out.