The Washington times., 1919-04-19

certainty the type OF aircraft which
will make it?
I'VE can fix on the type because
the flight is a purely physical matter,
like the transcontinental trip OF an
engine or motor car. Gasolene is the
great problem. And since we know
that every gallon Of gasolene weighs
about six pounds, and know how
much airplanes of different sizes will
carry, we can make some very ac-
curate calculations.
The maximum that any airplane
will safely carry as a load Cincluding
crew, oil, gasoline, food, etc.), is the
amount of its own weight. In other
words, the load of a machine must
rot exceed so per cent of the total
weight to be carried. II we start out
with the 90-horsepower motor, and
ask what its performance would
be, we will find certain conditions
debating its performance. The maxi
mum distance to be flown in crossing
the ocean is acknowledged to be
1900 miles. Allow Is per cent for
drift etc, and we have the equiva-
lent of 1000 miles. At 100 miles per
hour, which is certainly a high rate
of speed, a 9O-horsepower motor
would require twenty hours supply
of gas. Consuming about nine gal
Ions an hour, the motor would thus
need 1sO gallons as it's total supply,
or, in pounds, 6.2x1s0, or a total Of
1.116 pounds. This would make the
aeroplane weight about 5000 pounds,
which is too heavy a load for a 90
horsepower motor to carry econOm-
ically.
80 Gallons Per Hour.
"A 150-horsepower machine might
lift the required load. but two facts
prevent it from doing so in any
practical manner. The first is that
space is not available in the machine
for the gasoline. The second is that
the head resistance which would be
occasioned if it were loaded on would
not permit successful fight. A 4O05
horsepower Liberty or the Curtiss K-12
engine requires thirty-six gallons of
gasoline per hour, and this revives
the question of weight. as 5000
pounds of gasoline would have TO be
carried-obviously an impossibility.
even the three-motOred type Of
mammoth flying boat would not be
altogether feasible. In round figures,
10000 pounds Of gasOlene would have
to be carried. This could be done;
the N-C-l can carry a load OF over
$4,000 pounds, so that $1,000 pounds
would not pass the so per cent load
limit previously discussed, but a diff
fculty not mentioned as yet would
arise. Suppose one motor should
cease to function. The triple-motor-
ed airplane would be in the same po-
sition as the single-motored machine,
for the two motors would not sup
port ii in flight-certainly not until
il had completed one-half OF the trip
and accordingly lessened the load of
gasolene. and probably not until it
had covered three-foUrths Of the re-
quired ] 800 miles.
"But figures show that as we go up
to a four-motored flying boat we
have every reason to believe that the
problem would be solved. The pro-
portion OF weight carried to power
gradually increasing, il would here
reach a point where three motors
could support a flying craft which
would carry. ample gasolene to fly
from Newfoundland to Ireland and,
what is more important. make the
more difficult trip against the west
10 east winds which prevail at prac-
-ically all times. The problem of
what airplane can make the trans-At-'i
antic flight thus finds its solution. !
Boats are now being constructed on !
Ioth sides of the water which will |
meet the requirements Of the great |
ouruevD