The Bismarck tribune. [volume] (Bismarck, N.D.) 1916-current, 1931-04-07

PROPULSION n the feCnoE81n8 OF Dat
teries while running on the surface.
But they cannot be used under water.
When the craft Is submerged, motive
power. lighting, heating and all other
purposes r entirely dependent upon
the storage batteries.
When these become exhausted It is
imperative to come to the surface at
once to recharge before another sub
surface run can be made.
The fuel tanks Of the Nautilus give
her a surface cruising range Of about
5000 miles. but by filling the ballast
tanks, normally used in diving, with
oil, this would be extended to about
5000 miles.
While oil may be used for ballast
as well as water. still 1t a well with
In the range Of possibility that the
tanks may be needed in an emer-
gency, so that the oil in them would
have to be sacrificed.
In her original design the storage
batteries gave her a submerged cruis-
ing radius Of from IS to 90 miles, at
a speed of two knots. In Arctic tenn
peratures, however, the batteries
would be reduced to 10 per cent eff
ficiency, thus reducing the submerged
radius to AZ miles.
I have seen q statement attributed
to Commander Danenhower that the
Nautilus can traverse in 41.66 hours
at three knots, submerged, 125 miles.
But from the best available sources
of information I believe this state
ment or estimate to be in error, end
that mine Is more nearly in accord
ance with records Of the navy depart
ment, and more nearly correct.
Speed Cut Down
II my estimate Is correct, and the
Nautilus were to use the full battery
charge, with no reserve, It would take
81 hours to make A miles. Then she
would have to come to the surface
and spend eight hours in recnarging.
The amount OF fuel consumed in re-
charging Is equivalent to that con-
sumed in 100 miles Of surface cruising.
Considering together the 81 hours
Of cruising and the eight hours Of re-
charging while stationary, the crafts
average speed would be reduced to
one and one-half knots at best.
Hence to make 1900 miles SUBJ
merged it would require 1000 hours,
or about AZ days, provided that her
underwater cruising limits could be
distributed SO that at the end of each
battery limit she could come to the
surface, recharge, and proceed i'm
mediately. I believe, however. that
such will be far from the actual case.
Depth Is Limited
It must be remembered that the
diving limit of the submarine is about
200 feet. At a materially greater
depth the pressure would be beyond
her designed resistance, and would
cause disaster.
Even under open water, to man
euyer safely in this depth zone re-
quires the strictest care and attention
II disaster Is to be averted. Emer-
gencies frequently arise which neces-
state coming to the surface at once.
In the coming tower, where the
control lies, are the various instru-
ments and gauges. The craft is
steered by q gyro compass, which re-
quires constant electric, power to ope-
rate. The magnetic compass Is not
only unreliable in those latitudes; ii
is virtually useless. In fact, It prob
ably would be very misleading, and
might point in just the opposite d.
rection from the proper n There
would be no way Of detecting such
an error except by astronomical oh.
servations, which OF course would be
impossible when submerged.
II Compass Fails
Furthermore, as the pole Is ap-
preached, the gyro compass has less
directive force. Should 1t fail te
function from lack of mower to drive