Evening star. [volume] (Washington, D.C.) 1854-1972, 1931-10-12

Practicability Of a new method for
facilitating escape of lung equipped
submarine crews has been proved in
series Of deep-water tests conducted
recently in the Lower Potomac by Navy
diving experts.
The experiments, held secretly of
Morgantown, Md, confirmed previous
Laboratory" tests which showed that
unretarded ascent with the lung" sub
marine device does not seriously affect
the human system.
The new free ascent" method was
tested successfully for depths up to 100
feet and experiments at greater depths
are planned. The free ascent" plan,
eliminating the stop and count" sys-
tenn Of retarding ascents. showed that
member of stricken submarine crew
could be brought to the surface from
a depth of 100 feet in minute-about
one-thirteenth of the time required
under the old system.
The slow ascent method was adopted
when the lung" was adopted, on the
theory that a rapid rise through the
water would subject the human body
TO the peril Of the bends" dreaded
disease OF divers.
Tests OF Morgantown.
VI tIlc cApCl ulNlIlk
unit at the Washington Navy Yard con-
Quoted the tests off Morgantown, utiliz-
ing the diving launch Crilley.
Stimulating members of a crew trap
ped in a submarine, the Navy Yard
men assembled safely and quickly from
100 feet. The old method directed that
a man using the lung" would have
to use a rope. attached to a buoy, with
knots placed 10 feet apart in the line,
to gauge his distance upwards and per-
nit his system to become accustomed to
the changing depths of water.
Lieut. N. S. Ives, executive officer of
the diving school here. explained yes
terday that the first experiments were
conducted in the tank at the Wash
ington Navy Yard
Discussing the difference in the use
of the lung" Lieut. Ives explained:
"A diver breathes actual air through
his helmet and for this reason. it is
necessary for him to stop periodically,
as he ascends. A man who is breath
ing through the lung does not breathe
air, but Oxygen, and so reduces the
nitrogen content of his blood rapidly
and is taking no more of it into his
system. 1t can readily be seen that
the man using the lung has the adj
vantage over q diver.
I'VE did not know at first Just what
the effect would be, but tables of ascent
for the lung are considerably shorter
than the tables used by divers.
Forty men on an S boat, II all in
one compartment, under our new
method, can get out at the rate of
about one a minute, said Lieut.. Ives,
who was until recently commanding Of
ficer of the U. S. S. S-4, and is slated
to become commanding officer of the
diving school shortly.
Where the men had to stop on the
ascent, by counting on the line, there
was likelihood that they would get
punched up on the way. Further, it
put an excessive strain on the line
going up, which necessarily has to be
small. Then, too, there was the danger
that a man would get excited and
kick the mouth-pieces of the lung
out Of the mouth of the man below.
Work on New Method.
About six months ago we got to
work on the new method, whereby men
could come straight up, due to the
theory that they were breathing oxygen.
We started first in the pressure tank by
putting in air pressures to simulate the
water pressure. The officials at the
Diving School here started in at COM
paratively low preSsureS and worked
up in the tank to higher pressures, re-
producing as near as possible the actual
ascent from the depths. Conditions in
the tank do have the safety factor in
that a man can put his head up above
the water, so it was decided that the
experiments should be put to- an actual
outdoor test.
Last month, the diving boat was To-
Gated of Morgantown and the expert