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Thanks for the comments guys,
No Frank, I don't buy the stuff in cartons. ( Note
that the email was addressed to the psub wine-os)
At 300ft an average full lung volume of
6 liters will expand to 60 liters by the time you
hit the surface but only to 8.5
at the 200ft mark & then by another 6.5 liters
to the 100ft mark. Maybe if you ho-ho-hoed too much in the first
200ft
you could run yourself low on air. If you were
concerned about this & held back you risk an embolism, they say that
when you can feel your lungs expanding too much
its too late.
If you had a small air supply to rely on as
back up it may encourage more exhailing & make the trip safer.
With regard to floatation; Most people are pretty
well neutrally bouyant, some are negative. If you were comming up
from 300ft totally frozen & without bouyancy or
fins wouldn't it require the same effort as to swim horizontally underwater
for that distance fully clothed? Did the "Brits" mentioned have floatation? If 3 liters was
an overkill & took you up too fast,
maybe 1 liter would
have some benefit. With a plasticbag & the
valve open you could always squeeze air out or let it go.
It wouldn't be any
more complex than operating a BCD.
When you hit the surface you'd have floatation.
Nice if you came up successfully from 300ft & there was no boat about
& you drowned.
Am a scuba diver of 20+ years but have never done
an emergency accent from any great depth so I'm only hypothesising.
Thanks Dean thats encouraging will have a
go.
Regards Alan
----- Original Message -----
Sent: Wednesday, August 05, 2009 9:40
AM
Subject: RE: [PSUBS-MAILIST] escape from
sub
Alan,
You
will never get a chance to take a breath off of it on ascent as it will be
pulling you too fast. In addition, you don?t want to take a breath on a
speedy ascent?if you did, you would probably rupture a lung. The Brits
who did the ascents from 600+ ft. went up all of the way with only their
initial breath at the bottom. You should be exhaling almost continuously
on the way up. Our Navy has you saying HO-HO-HO all of the way to the
surface.
R/Jay
Resepectfully,
Jay K.
Jeffries
Andros
Is., Bahamas
Save the
whales, collect the whole set.
Hi Alan. Have you been drinking a lot of wine? How many bags have you
saved up?
Just kidding.......as a scuba diver, I can tell you that won't work. If
we are escaping from a sub, the last thing we need is a bag full of air to
deal with. If we get pressurized at depth, make it out the hatch, and
head for the surface, we probably won't even need scuba tanks. The air in your
lungs expands as you rise, quite a lot.
The danger of rupturing your lungs is very real, so scuba training is
essential.
The 40 cu.ft. scuba bottles used for escape are mostly for breathing
while the sub floods, and climbing out through the hatch. If it's really
deep, maybe a short de-compression stop near the surface if we're still
conscious, but mostly we will be shooting to the surface with whatever
floatation device we have, and blowing out air as it expands in our lungs.
Frank D.
From:
owner-personal_submersibles@psubs.org
[mailto:owner-personal_submersibles@psubs.org] On Behalf Of Alan
James
Sent: Tuesday, August 04, 2009 5:31 PM
To:
personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] escape
from sub
I've always
thought that the inner plastic bag that contains the wine in a 3 liter
cardboard wine cask
would make a good
emergency floatation device for fishing; but would be even better for small
subs.
You could roll it
up (once emptied) stick rubber bands around it & put it in your
pocket.
A cord attached
around the neck (of the bag) could have a loop for your wrist on the other
end.
While the sub is
filling with water you blow into the bag. This will expand to 24 liters from
200ft
so there should be
a few breaths of air from it on the way up. You would need to work the valve
in
the process &
avoid taking too many breaths in the first 100ft.
I'll try it out
when the weather gets warmer, its the middle of winter down
here.
It might be better
than nothing & its free.
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