[PSUBS-MAILIST] onboard gear
MerlinSub@t-online.de via Personal_Submersibles
personal_submersibles at psubs.org
Sun Apr 28 09:56:46 EDT 2019
Rick we never discuss the co2 type. We discuss the BCD with the air pony
bottle.
-----Original-Nachricht-----
Betreff: Re: [PSUBS-MAILIST] onboard gear
Datum: 2019-04-28T01:00:42+0200
Von: "Rick Patton via Personal_Submersibles"
<personal_submersibles at psubs.org>
An: "Personal Submersibles General Discussion"
<personal_submersibles at psubs.org>
I used to have a BC back around 1968 that was called a Buoy Fenzy and it
had it's own pony bottle attached to it for inflation and you could re fill
the bottle by attaching it to a scuba tank to equalize or have shop fill
it.
It had a lot more volume than the CO2 inflation type and had a hose with a
mouth piece and button to push to breath out of it if you had to.
I haven't seen them for ages so must not be made anymore but this would be
great to have on board for escape as it would give you a lot more air at
depth than the CO2 type and you could breath off of it without loosing any
air like a closed circuit system and a bit more air to breath as it
expanded on ascent.
Rick
On Sat, Apr 27, 2019 at 4:11 AM MerlinSub at t-online.de
<mailto:MerlinSub at t-online.de> via Personal_Submersibles <
personal_submersibles at psubs.org <mailto:personal_submersibles at psubs.org> >
wrote:
Why you want to breath the first minute of your fly?
Just ensure that the gas can get out of our lungs to not overpressure it.
And by the way - if you not breath you can not get additional gas which
can expant into your blood.
And how long you can stop breathing has more to do with your brain - than
with your lungs.
I am now 54 and can stop not more than 1 minute. In my best time and with
training it was easy over 2.
But this is pure theoretical. The best equipment to surfive a submarine
exit is - training.
The lung can overexpant easy but this will happend more or less on the
last 10 meters to the surface.
If you have the training and expierence to slow down your speed there it
will help a lot.
-----Original-Nachricht-----
Betreff: Re: [PSUBS-MAILIST] onboard gear
Datum: 2019-04-27T05:24:20+0200
Von: "Alan via Personal_Submersibles" <personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
An: "Personal Submersibles General Discussion" <
personal_submersibles at psubs.org <mailto:personal_submersibles at psubs.org>
>
Thanks Tom, a lot to think about.
Yes breathing from the BCD could be problematic on a deep ascent as the
gas would be expanding very little over the first few hundred feet & as
you
say you could easily consume it & reduce your flotation.
Alan
On 27/04/2019, at 2:24 PM, TOM WHENT via Personal_Submersibles <
personal_submersibles at psubs.org <mailto:personal_submersibles at psubs.org>
> wrote:
That is a whole lot of task loading for an emergency. Chances are
little of this will be reflexive from repeated practice. Having a
good non narcotic gas to breathe during flood/exit procedures would
be beneficial in keeping your head. Keep in mind that helium on
boards 2.7 times faster than nitrogen and also comes out of your
tissues that much faster. Too much time breathing on it might cause
you to be severely bent before reaching the surface on a fast ascent.
Most helium bends occur under water and it will even off gas through
your eyes. I've never experienced this but I have heard that it is
painful.
Breathing from a BCD seems like a bad idea to me. It would be
marginally passable as long as you are certain that you are
ascending. Accidentally wasting or venting your buoyancy gas would be
disastrous. Many trained divers struggle with buoyancy control and
can't manipulate inflators with cold hands or in panic.
Coming up fast from any depth, you will need to ensure that you are
exhaling continually, or able to breath in and out so that your
airway is never closed. You have no pain mechanism in your body to
alert you to a lung overpressure. If you rupture a lung you have no
chance of survival even if you do reach the surface.
I had thought about the idea of wearing a neoprene wetsuit inside the
sub as an alternate means of buoyancy and environmental protection
but after considering the depths you guys are escaping from, that too
would have minimal buoyancy due to the crush on the suit from the
pressure. It would however provide some warmth, even if marginally.
Whatever solution you choose, it will have to be simple enough to
deploy under the worst conditions imaginable and preferably protect
your airway on the surface if you should lose consciousness.
I'm generally not an advocate of full face masks for scuba diving,
but in this circumstance, if you had one and a means of flotation,
you would stand a better chance of survival than using a regulator
(or BCD inflator) which will fall out of your mouth if you lose
consciousness. You generally cannot use the firefighter style face
mask, but must use one designed for diving. The reason being that the
latter will have a flexible nose pocket to allow you to pinch it for
equalizing.
The hood and escape suits look better all the time.
Tom
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On Fri, Apr 26, 2019 at 8:14 PM -0400, "Alan via
Personal_Submersibles" <personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> > wrote:
Carsten,
yes you could rely on air out of your BCD but it is not regarded as
a good
practice because of disinfectants used to clean out BCDs. You would
need
to find a suitable sterilising product. But this is an emergency!
I think maybe, as I have said, an escape plan for every 100 ft
based on the
volume of your sub, how quickly you can flood it, how quickly you
can equalise
your ears & what mixed gas you need to avoid getting narced, bent &
O2
Poisoning. Beyond certain depths you would need to start breathing
mixed
gas from a pony bottle or whatever as the hull equalised.
Now you have me thinking!!! What about an external scuba tank full
of mixed
gas plumbed through to the cabin to breath from during the flooding
of the hull,
this would give you a lot more time to equalise your ears! Plumb
this tank to
act as a reserve ballast blow so it is not wasted. Leave the sub
with the pony
bottle full of mixed gas & inflate the horseshoe BCD with it, then
breath from
the BCD.
Alan
On 27/04/2019, at 9:45 AM, MerlinSub at t-online.de
<mailto:MerlinSub at t-online.de> via Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> > wrote:
Alan the pony is just for the first filling the vest in the
moment you leave the sub.
During the fast as possible way to the surface the air in the
vest expand all the
time and leave via the overpressure valve.
Imagine you have a vest of say 4 Liter. How much air will be in
if you leave the sub in 100 meter deeps?
Right - around 40 liters. During your way to the surface 36
liters will leave via the overpressure vale.
Pretty much air to breath. The pony bottle is just there for
the first filling- so you have not to fill tthe
vest wih your lungs because this is exhaust gas and the process
may exhaust you also.
A filled 220 bar by 0,5 Liter pony bottle contains 110 liter
expand gas.
If we assume the vest has 4 Liters volume you can fill the vest
up to a depth equal to 27 bar or 270 meter dephts.
And you can breath all these 110Liter air from the vest except
the last 4 liters which you need on the surface
for bouancy.
In real life it is may better first to leave the sub and than
open the valve to fill the vest.
Otherwise it makes you more bulky and you have the possibility
to scratch the vest somewere on your sub exit.
If you have no expiernce with such vest you should traning it
in a 2-4 meter depth pool to get an feeling for it.
On Euronaut we have all that gear on board. Scuba vest, Steinke
hoods and dive gear including suits.
On a emergency exit of a sunen military argentinna submarnne
which was sunken in the 80ies or 90ies some crew members manage
to escape from 40 meter depth. The guys with the Steinke Hoods
and no dive expierence survifed all.
The colleges with the scuba expierence use the dive gears -
help the other guys to get out -
and died later on decompression thickness. :-(
-----Original-Nachricht-----
Betreff: Re: [PSUBS-MAILIST] onboard gear
Datum: 2019-04-26T23:03:14+0200
Von: "Alan via Personal_Submersibles" <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
An: "Personal Submersibles General Discussion" <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
Sean / all,
the cold will certainly be a factor but you will be exposed to
that for some
time while the submarine fills with water & equalises. So the
extra 15 seconds
grabbing an external tank won't be major.
What I fear most is bursting my ear drums, & freezing water in
the inner ear.
I imagine this would be very painful, maybe like brain freeze,
but I am only guessing.
Some people have more problems than others equalising & once
you start to
feel pain in your ear from pressure it is more difficult to
equalise.
I think some control on the flooding speed to let you equalise
your ears would
be an asset. Pitty to burst your ear drums when you might be
doing a simple
escape from 100ft.
As Emile & Carsten showed with their practice escapes; they
could get out
relatively easily, & with a bit of air ( 6 cu ft pony bottle )
you could get to the
surface easy enough.
If I were escaping from deeper I would use a pony bottle with
mixed gas some
time after the equivalent of 150ft & this would buy me a bit of
time to equalise
& save my ears, then escape & use my large mixed gas tank to go
to the surface
making stops if I felt able.
There is sense in you saying Keep It Simple, but if you pre
plan & practice, a
more complex but safer escape is possible. Maybe work out how
long it is going
to take to fill your particular sub at varying depths, how
quickly you could equalise
for varying depths. How long your pony bottle would last you &
have a knowledge
of what stops would be best for the varying depths you may
escape from.
At least that would take away a lot of the fear of the unknown
& reduce panic.
BTW I am a diver & amateur speleologist so used to cold wet
tight spaces.
Alan
On 27/04/2019, at 12:17 AM, Sean T. Stevenson via
Personal_Submersibles <personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> > wrote:
Alan - Don't overthink this. A buoyant emergency ascent can
get you to the surface in less than 60 seconds if you are
not purposefully attempting to limit your ascent rate. How
long can you hold your breath (not that you should)? A gas
source helps you avoid a hypoxic blackout, but with a hood
of any description you shouldn't drown. You'll just end up
rebreathing some of the hood gas. As we discussed earlier,
hypothermia will be an issue, as will the exposure time -
it is actually better to get up from depth ASAP than to
spend time messing around at depth and then having a bunch
of stuff slowing your ascent while deep. My point about the
gas consumption was to illustrate how impractical it would
be to carry sufficient gas to enable an ascent as a diver
would do it.
Sean
-------- Original Message --------
On Apr 25, 2019, 23:39, Alan via Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> > wrote:
More thoughts on escape...
Went in to a couple of dive shops today looking at pony
bottles.
The smallest they were selling were 19 cu ft. I did see
a 13 cu ft they were
filling. Both looked too big for my intended dual
purpose use of a horse shoe
BCD as a life jacked. A bit clutsy getting in to the
sub wearing a BCD & large
tank. They make a 6 cu ft pony bottle but I would have
to import it & it would
only get me to the surface from about 100ft.
I had the thought of filling a 6 cu ft pony bottle with
mixed gas & having an
80 cuft mixed gas tank outside the hull. It could have
an octopus regulator
( to avoid free flow) permanently on the 80 & a quick
disconnect fitting on it that
a hose attaches to for use as a reserve ballast blow.
So you breath through your pony reg while flooding &
escaping, then when
outside use the 80 cu ft tank reg while detaching the
ballast hose, attaching
the BCD connection and un latching the tank.
It could be practiced in the garage with your eyes
closed & done in about 15
seconds. Any thoughts on this?
Alan
On 26/04/2019, at 1:38 PM, Alan via
Personal_Submersibles <personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> > wrote:
Thanks Carsten,
I am thinking I may go with something similar; a
horse collar BCD with a
13 cu ft pony bottle. (BCD below).
It could double as a life jacket, has manual
inflation & push button inflation.
I would have a regulator off the pony bottle as
well.
The BCD has an over inflation valve but if you
wanted your air to last in an emergency
you could breath expanding air out of the BCD
through the manual inflation
mouth piece. With a BCD as apposed to a life jacket
you have the chance to
slow your ascent & do a decompression stop.
I am not sure what the maximum depth is that I
could come up from with a 13 cu ft
tank.
I could use this for shallow dives or as a
supplement for snorkelling, so it won't be
sitting in a sub doing nothing.
Alan
<image1.PNG>
On 25/04/2019, at 7:42 PM, MerlinSub at t-online.de
<mailto:MerlinSub at t-online.de> via
Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> > wrote:
We figure out that the best escape equipment
will be a Steinke hood (hard to get now)
or a traditional scuba west with a small on
board air bottle.
Both give you the high lift capacity you need
to make an fast rise.
For bigger subs and cold waters light diving
suits will help muxh.
Second it will help you a lot if you allready
a diver or had make a course.
We make some years ago some exercieces with a
semi finish Psub scuttled in a pool .
First go out were really bad feelings and
schock about the water rush in and the cold and
so.Have these in mind: panic.
But after 3-4 times and with the knowledge it
was fun to do the escape exercice.
With training and the right gear I see no
problem to get out of a sub even from much
greater dephts.
The releasing signal bouy should have a stopper
on the reel. Otherwise a 300 m rope bouy will
drived far away with a sub sunken in 30 m .
And make the life of the rescue diver much
harder. The rope shall resitance the force a
human can pull on it - say 150 Kg at least.
Somebody on the surface can come to the
conclusion to lift the baot on these rope-
better make a mark on the Bouy "Sunken
submarine - dont pull on the rope!"
vbr Carsten
-----Original-Nachricht-----
Betreff: Re: [PSUBS-MAILIST] onboard gear
Datum: 2019-04-25T00:07:11+0200
Von: "Alan via Personal_Submersibles" <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
An: "Personal Submersibles General Discussion"
<personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
Perhaps a Psub plan for escape from down to
100ft, as you could do this
100 times out of 100 if you knew what you were
doing.
Also even though most subs are capable of
diving deeper there is more
probability that entanglements like ropes &
nets are going to be encountered
In shallower depths.
BTW the pressure in the sub is going to
increase incrementally quicker as it
floods & you need to keep equalising your ears
like mad toward the end or
you'll burst your ear drums, & aside from that
pain, will have freezing water
going in to your inner ear. That would increase
your chances of failure.
Alan
On 24/04/2019, at 4:12 PM, Stephen Fordyce via
Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
wrote:
Hi all,
This is an interesting discussion I've been
meaning to weigh in on - as an experienced
tech/deep/cave diver rather than a sub
person.
My feel is that unless the escapee is an
experienced diver (and even then), the
chances of a successful escape from below
50m/150ft depth are so low as to be almost
negligible. And I'd suggest having a plan
for such is (almost) an entirely false
sense of security - and energy should be
diverted elsewhere to reduce risk.
A few of the scarier things like narcosis
and the bends have had a lot of airtime,
but basic stuff like keeping a diving mask
clear (and one that's probably fogging up),
panic-breathing a soggy SCUBA reg and
dealing with the thermal shock of sudden
immersion are likely to cause death by
drowning much earlier. Don't underestimate
the thermal shock and how useless it makes
you with no exposure suit. Breathing a
regulator without a mask is a skill in
itself. You're probably already suffering
from fatigue, stress, high CO2 and/or low
O2 from waiting for rescue and getting to
such a desperate point. All of these cause
significant mental impairment before you
even start on the escape.
Forget about planning to hold stops on the
way up, switch gases or do decompression.
Even if you're lucky enough to still be
conscious and thinking in the latter stages
of the rapid ascent, personal buoyancy
control is unlikely to be possible.
So if you're going to attempt to escape, I
suggest the best chance for survival is to
plan on a very simple setup (per person),
buoyancy for a rapid/undignified ascent,
and needing urgent medical attention and
oxygen on the surface. Maybe carry a
cylinder of trimix on board to give
yourself a better chance of being able to
think, but it's a big weight/cost premium
if it's enough to be useful. Use a divers
(with closed bottom) "lift bag" and a loop
around at the armpits as a quick and easy
way to get a person shooting upwards. CO2
inflatable life jacket to keep unconscious
head above water on surface. (Inflate at
depth while conscious - won't fill much,
but will expand on way up) Might be better
put towards things like extra life support
duration. Consider doing regular practise
drills that are as realistic as possible.
Highly skilled divers mess up basic skills
in stressful situations and die with sad
regularity. Don't imagine your (and
passengers) chances of winging it at depth
will be anything other than tiny. 30m/90ft
and shallower they are a bit better.
I hate to be negative, but perhaps for deep
PSUB diving, the inability to escape is
just one of those residual risks that can
be accepted for a recreational activity.
Cheers,
Steve Fordyce
Melbourne, Australia
On Wed, 24 Apr 2019 10:57 hank pronk via
Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
wrote:
I think all submarines should have an
escape pod or jettisoning occupant
sphere. I admit I made a mistake with my
escape pod by making it only for one. An
easy fix that I will likely tackle, and
that is to stretch the pod making it big
enough for two. E3000 has a jettisoning
occupant sphere.
Hank
On Tuesday, April 23, 2019, 5:39:01 PM
MDT, TOM WHENT via Personal_Submersibles
<personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org>
> wrote:
A compact bail out rebreather might be
the most surviveable solution however it
would require a significant commitment in
training, maintenance as well as the cost
of the equipment itself. I personally
have not been following the development
of bailout rebreathers, although i'm
aware that some are working on this. My
dive group relies on planning for open
circuit bailout in the event of
rebreather failure.
If money is no object, I am partial to
the ISC Megalodon classic CCR. In terms
of robustness and deep water capability,
you will find none better.
It will get you home and flies itself. It
is an electronic CCR which maintains PPO2
for the user. This is the unit I dive
myself and feel very confident in.
KISS classics, which are a simple and
reliable mechanical CCR apparatus, often
come up on the used market in affordable
price ranges.
Both would require significant equipment
specific training but would get you out
of a 400 ft jam with only two small
cylinders and gas to spare. CCR duration
is driven by metabolic rate and is the
same irrespective of operational depth.
Even the lowest end units will give you
an hour plus.
On ascent, rebreathers do require the
diver to be monitoring the oxygen level
display in the breathing loop and very
likely adding oxygen manually -
particularly in the mCCR type on a fast
ascent.
The other benefit of this setup is that
an air cell for buoyancy can be
integrated easily in one compact package.
It sounds like a lot of effort for the
non diver, but it is a functional answer
to the risks of a sub disabled in deep
water.
What is a life worth?
How much risk can one accept for a hobby?
Food for thought anyhow.
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On Tue, Apr 23, 2019 at 7:34 PM -0400,
"Alan via Personal_Submersibles" <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org>
> wrote:
As an alternative to possible death or
even worse, the loss of your submarine,
I am in early stages of designing a buoy
release mechanism that is used
for surfacing safely but has an emergency
beacon that can be activated
with an electro magnet.
Thoughts are to use 150 lb braid with a
tensioning mechanism & have an
automatic boat latch mechanism that can
slide down the braid but is fixed
to the buoy with instructions, "tie a
long rope to the ring & let down untill
latch attaches to submarine. Pull up"
The automatic latch is a device that Phil
described & provided a drawing for,
but there may be a cheap & suitable
automatic boat latch ( used on release
& retrieve on boat launching) on the
market. I am still searching & if anyone
knows of one that may be suitable I would
be interested.
Alan
On 24/04/2019, at 10:51 AM, Sean T.
Stevenson via Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org>
> wrote:
There is a significant difference
between submarine escape and a
planned SCUBA dive with regard to
both the dive profile and the
equipment that you can reasonably
carry. An escape is more akin to
what is known as a buoyant emergency
ascent in recreational diving, where
you need to get to the surface
yesterday and all other
considerations are secondary. In
this specific case, trying to keep to
a slow ascent rate would
significantly increase the incurred
decompression obligation that you
must necessarily then blow off as you
ascend through the shallows,
introducing an even greater risk.
You also have the hypothermia issue
to deal with if you are not equipped
with exposure protection specifically
intended for submersion at depth.
Being cold reduces decompression
effectiveness. In order to keep to a
target ascent rate or perform
decompression stops, you would need
diving instrumentation (depth gauge
and timer), would need the skills and
experience to perform gas switches
and hold stops, and would need
significantly more bulky equipment to
have enough gas to perform a proper
decompression (slow ascent, gas
switches, etc.).
When I dive to these depths on SCUBA,
I wear twin cylinders (>100 cu. ft.
each) on my back with the bottom gas
(10/70 or whatever for the planned
depth and time), plus three or four
off-board cylinders (80s) carrying
the decompression gases (typically
21/35, 35/25, EAN50 and oxygen), plus
a small bottle of argon for drysuit
inflation. Obviously, as an escapee
you are not so equipped. Far better
to lockout as quickly as possible and
rapidly ascend (with buoyant assist)
to get clear of those depths where
you are ongassing the most, and if at
all possible, to slow the ascent as
you approach the surface, and then
have your surface support or
emergency responders administer
oxygen as transport is arranged to
recompression. To be clear, an
emergency escape from a disabled
submarine at these depths is not even
remotely a good idea - it is simply a
marginally better idea than dying on
the bottom.
To illustrate, if you were to attempt
a continuous ascent from 300 fsw, the
average depth is 150 fsw, which is
about 5.5 atmospheres absolute. If
you assume a surface air consumption
rate of 1 cu. ft. / minute (high, but
typical of a diver who is stressed or
working hard, which is inevitable in
a submarine escape scenario), that
corresponds to 5.5 cu. ft. / min at
the average depth of the ascent. At
a 30 ft/min ascent rate, that's 10
minutes, or 55 cu. ft. of gas
consumed just for the continuous
ascent with no decompression stops,
without consideration for the gas
consumed while blowing down and
locking out. You can judge for
yourself the practicality of carrying
an 80 on a PSub sized vessel just for
emergency escape purposes.
Sean
‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Tuesday, April 23, 2019 12:32 PM,
David Colombo via
Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org>
> wrote:
Hi Guys, This topic is
fascinating and scary at the same
time. Accent rates form the old
Navy logs had 60ft / minute max
with a recommended max accent
rate of 30 ft/ min. At 300ft
escape depth, what volume of
mixed gases would you need for a
10 minute accent assuming you
choose not to swim 60ft/min.
Best Regards,
David Colombo
804 College Ave
Santa Rosa, CA. 95404
(707) 536-1424
www.SeaQuestor.com
<http://www.SeaQuestor.com>
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As an alternative to possible death or
even worse, the loss of your submarine,
I am in early stages of designing a buoy
release mechanism that is used
for surfacing safely but has an emergency
beacon that can be activated
with an electro magnet.
Thoughts are to use 150 lb braid with a
tensioning mechanism & have an
automatic boat latch mechanism that can
slide down the braid but is fixed
to the buoy with instructions, "tie a
long rope to the ring & let down untill
latch attaches to submarine. Pull up"
The automatic latch is a device that Phil
described & provided a drawing for,
but there may be a cheap & suitable
automatic boat latch ( used on release
& retrieve on boat launching) on the
market. I am still searching & if anyone
knows of one that may be suitable I would
be interested.
Alan
On 24/04/2019, at 10:51 AM, Sean T.
Stevenson via Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org>
> wrote:
There is a significant difference
between submarine escape and a
planned SCUBA dive with regard to
both the dive profile and the
equipment that you can reasonably
carry. An escape is more akin to
what is known as a buoyant emergency
ascent in recreational diving, where
you need to get to the surface
yesterday and all other
considerations are secondary. In
this specific case, trying to keep to
a slow ascent rate would
significantly increase the incurred
decompression obligation that you
must necessarily then blow off as you
ascend through the shallows,
introducing an even greater risk.
You also have the hypothermia issue
to deal with if you are not equipped
with exposure protection specifically
intended for submersion at depth.
Being cold reduces decompression
effectiveness. In order to keep to a
target ascent rate or perform
decompression stops, you would need
diving instrumentation (depth gauge
and timer), would need the skills and
experience to perform gas switches
and hold stops, and would need
significantly more bulky equipment to
have enough gas to perform a proper
decompression (slow ascent, gas
switches, etc.).
When I dive to these depths on SCUBA,
I wear twin cylinders (>100 cu. ft.
each) on my back with the bottom gas
(10/70 or whatever for the planned
depth and time), plus three or four
off-board cylinders (80s) carrying
the decompression gases (typically
21/35, 35/25, EAN50 and oxygen), plus
a small bottle of argon for drysuit
inflation. Obviously, as an escapee
you are not so equipped. Far better
to lockout as quickly as possible and
rapidly ascend (with buoyant assist)
to get clear of those depths where
you are ongassing the most, and if at
all possible, to slow the ascent as
you approach the surface, and then
have your surface support or
emergency responders administer
oxygen as transport is arranged to
recompression. To be clear, an
emergency escape from a disabled
submarine at these depths is not even
remotely a good idea - it is simply a
marginally better idea than dying on
the bottom.
To illustrate, if you were to attempt
a continuous ascent from 300 fsw, the
average depth is 150 fsw, which is
about 5.5 atmospheres absolute. If
you assume a surface air consumption
rate of 1 cu. ft. / minute (high, but
typical of a diver who is stressed or
working hard, which is inevitable in
a submarine escape scenario), that
corresponds to 5.5 cu. ft. / min at
the average depth of the ascent. At
a 30 ft/min ascent rate, that's 10
minutes, or 55 cu. ft. of gas
consumed just for the continuous
ascent with no decompression stops,
without consideration for the gas
consumed while blowing down and
locking out. You can judge for
yourself the practicality of carrying
an 80 on a PSub sized vessel just for
emergency escape purposes.
Sean
‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Tuesday, April 23, 2019 12:32 PM,
David Colombo via
Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org>
> wrote:
Hi Guys, This topic is
fascinating and scary at the same
time. Accent rates form the old
Navy logs had 60ft / minute max
with a recommended max accent
rate of 30 ft/ min. At 300ft
escape depth, what volume of
mixed gases would you need for a
10 minute accent assuming you
choose not to swim 60ft/min.
Best Regards,
David Colombo
804 College Ave
Santa Rosa, CA. 95404
(707) 536-1424
www.SeaQuestor.com
<http://www.SeaQuestor.com>
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Carsten,
yes you could rely on air out of your BCD but it is not regarded as a
good
practice because of disinfectants used to clean out BCDs. You would
need
to find a suitable sterilising product. But this is an emergency!
I think maybe, as I have said, an escape plan for every 100 ft based
on the
volume of your sub, how quickly you can flood it, how quickly you can
equalise
your ears & what mixed gas you need to avoid getting narced, bent &
O2
Poisoning. Beyond certain depths you would need to start breathing
mixed
gas from a pony bottle or whatever as the hull equalised.
Now you have me thinking!!! What about an external scuba tank full of
mixed
gas plumbed through to the cabin to breath from during the flooding
of the hull,
this would give you a lot more time to equalise your ears! Plumb this
tank to
act as a reserve ballast blow so it is not wasted. Leave the sub with
the pony
bottle full of mixed gas & inflate the horseshoe BCD with it, then
breath from
the BCD.
Alan
On 27/04/2019, at 9:45 AM, MerlinSub at t-online.de
<mailto:MerlinSub at t-online.de> via Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> > wrote:
Alan the pony is just for the first filling the vest in the
moment you leave the sub.
During the fast as possible way to the surface the air in the
vest expand all the
time and leave via the overpressure valve.
Imagine you have a vest of say 4 Liter. How much air will be in
if you leave the sub in 100 meter deeps?
Right - around 40 liters. During your way to the surface 36
liters will leave via the overpressure vale.
Pretty much air to breath. The pony bottle is just there for the
first filling- so you have not to fill tthe
vest wih your lungs because this is exhaust gas and the process
may exhaust you also.
A filled 220 bar by 0,5 Liter pony bottle contains 110 liter
expand gas.
If we assume the vest has 4 Liters volume you can fill the vest
up to a depth equal to 27 bar or 270 meter dephts.
And you can breath all these 110Liter air from the vest except
the last 4 liters which you need on the surface
for bouancy.
In real life it is may better first to leave the sub and than
open the valve to fill the vest.
Otherwise it makes you more bulky and you have the possibility to
scratch the vest somewere on your sub exit.
If you have no expiernce with such vest you should traning it in
a 2-4 meter depth pool to get an feeling for it.
On Euronaut we have all that gear on board. Scuba vest, Steinke
hoods and dive gear including suits.
On a emergency exit of a sunen military argentinna submarnne
which was sunken in the 80ies or 90ies some crew members manage
to escape from 40 meter depth. The guys with the Steinke Hoods
and no dive expierence survifed all.
The colleges with the scuba expierence use the dive gears - help
the other guys to get out -
and died later on decompression thickness. :-(
-----Original-Nachricht-----
Betreff: Re: [PSUBS-MAILIST] onboard gear
Datum: 2019-04-26T23:03:14+0200
Von: "Alan via Personal_Submersibles" <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
An: "Personal Submersibles General Discussion" <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
Sean / all,
the cold will certainly be a factor but you will be exposed to
that for some
time while the submarine fills with water & equalises. So the
extra 15 seconds
grabbing an external tank won't be major.
What I fear most is bursting my ear drums, & freezing water in
the inner ear.
I imagine this would be very painful, maybe like brain freeze,
but I am only guessing.
Some people have more problems than others equalising & once you
start to
feel pain in your ear from pressure it is more difficult to
equalise.
I think some control on the flooding speed to let you equalise
your ears would
be an asset. Pitty to burst your ear drums when you might be
doing a simple
escape from 100ft.
As Emile & Carsten showed with their practice escapes; they could
get out
relatively easily, & with a bit of air ( 6 cu ft pony bottle )
you could get to the
surface easy enough.
If I were escaping from deeper I would use a pony bottle with
mixed gas some
time after the equivalent of 150ft & this would buy me a bit of
time to equalise
& save my ears, then escape & use my large mixed gas tank to go
to the surface
making stops if I felt able.
There is sense in you saying Keep It Simple, but if you pre plan
& practice, a
more complex but safer escape is possible. Maybe work out how
long it is going
to take to fill your particular sub at varying depths, how
quickly you could equalise
for varying depths. How long your pony bottle would last you &
have a knowledge
of what stops would be best for the varying depths you may escape
from.
At least that would take away a lot of the fear of the unknown &
reduce panic.
BTW I am a diver & amateur speleologist so used to cold wet tight
spaces.
Alan
On 27/04/2019, at 12:17 AM, Sean T. Stevenson via
Personal_Submersibles <personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> > wrote:
Alan - Don't overthink this. A buoyant emergency ascent can
get you to the surface in less than 60 seconds if you are not
purposefully attempting to limit your ascent rate. How long
can you hold your breath (not that you should)? A gas source
helps you avoid a hypoxic blackout, but with a hood of any
description you shouldn't drown. You'll just end up
rebreathing some of the hood gas. As we discussed earlier,
hypothermia will be an issue, as will the exposure time - it
is actually better to get up from depth ASAP than to spend
time messing around at depth and then having a bunch of stuff
slowing your ascent while deep. My point about the gas
consumption was to illustrate how impractical it would be to
carry sufficient gas to enable an ascent as a diver would do
it.
Sean
-------- Original Message --------
On Apr 25, 2019, 23:39, Alan via Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> > wrote:
More thoughts on escape...
Went in to a couple of dive shops today looking at pony
bottles.
The smallest they were selling were 19 cu ft. I did see a
13 cu ft they were
filling. Both looked too big for my intended dual purpose
use of a horse shoe
BCD as a life jacked. A bit clutsy getting in to the sub
wearing a BCD & large
tank. They make a 6 cu ft pony bottle but I would have to
import it & it would
only get me to the surface from about 100ft.
I had the thought of filling a 6 cu ft pony bottle with
mixed gas & having an
80 cuft mixed gas tank outside the hull. It could have an
octopus regulator
( to avoid free flow) permanently on the 80 & a quick
disconnect fitting on it that
a hose attaches to for use as a reserve ballast blow.
So you breath through your pony reg while flooding &
escaping, then when
outside use the 80 cu ft tank reg while detaching the
ballast hose, attaching
the BCD connection and un latching the tank.
It could be practiced in the garage with your eyes closed
& done in about 15
seconds. Any thoughts on this?
Alan
On 26/04/2019, at 1:38 PM, Alan via Personal_Submersibles
<personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> > wrote:
Thanks Carsten,
I am thinking I may go with something similar; a
horse collar BCD with a
13 cu ft pony bottle. (BCD below).
It could double as a life jacket, has manual
inflation & push button inflation.
I would have a regulator off the pony bottle as well.
The BCD has an over inflation valve but if you wanted
your air to last in an emergency
you could breath expanding air out of the BCD through
the manual inflation
mouth piece. With a BCD as apposed to a life jacket
you have the chance to
slow your ascent & do a decompression stop.
I am not sure what the maximum depth is that I could
come up from with a 13 cu ft
tank.
I could use this for shallow dives or as a supplement
for snorkelling, so it won't be
sitting in a sub doing nothing.
Alan
<image1.PNG>
On 25/04/2019, at 7:42 PM, MerlinSub at t-online.de
<mailto:MerlinSub at t-online.de> via
Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> > wrote:
We figure out that the best escape equipment will
be a Steinke hood (hard to get now)
or a traditional scuba west with a small on board
air bottle.
Both give you the high lift capacity you need to
make an fast rise.
For bigger subs and cold waters light diving
suits will help muxh.
Second it will help you a lot if you allready a
diver or had make a course.
We make some years ago some exercieces with a
semi finish Psub scuttled in a pool .
First go out were really bad feelings and schock
about the water rush in and the cold and so.Have
these in mind: panic.
But after 3-4 times and with the knowledge it was
fun to do the escape exercice.
With training and the right gear I see no problem
to get out of a sub even from much greater
dephts.
The releasing signal bouy should have a stopper
on the reel. Otherwise a 300 m rope bouy will
drived far away with a sub sunken in 30 m .
And make the life of the rescue diver much
harder. The rope shall resitance the force a
human can pull on it - say 150 Kg at least.
Somebody on the surface can come to the
conclusion to lift the baot on these rope- better
make a mark on the Bouy "Sunken submarine - dont
pull on the rope!"
vbr Carsten
-----Original-Nachricht-----
Betreff: Re: [PSUBS-MAILIST] onboard gear
Datum: 2019-04-25T00:07:11+0200
Von: "Alan via Personal_Submersibles" <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
An: "Personal Submersibles General Discussion" <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
Perhaps a Psub plan for escape from down to
100ft, as you could do this
100 times out of 100 if you knew what you were
doing.
Also even though most subs are capable of diving
deeper there is more
probability that entanglements like ropes & nets
are going to be encountered
In shallower depths.
BTW the pressure in the sub is going to increase
incrementally quicker as it
floods & you need to keep equalising your ears
like mad toward the end or
you'll burst your ear drums, & aside from that
pain, will have freezing water
going in to your inner ear. That would increase
your chances of failure.
Alan
On 24/04/2019, at 4:12 PM, Stephen Fordyce via
Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> > wrote:
Hi all,
This is an interesting discussion I've been
meaning to weigh in on - as an experienced
tech/deep/cave diver rather than a sub
person.
My feel is that unless the escapee is an
experienced diver (and even then), the
chances of a successful escape from below
50m/150ft depth are so low as to be almost
negligible. And I'd suggest having a plan for
such is (almost) an entirely false sense of
security - and energy should be diverted
elsewhere to reduce risk.
A few of the scarier things like narcosis and
the bends have had a lot of airtime, but
basic stuff like keeping a diving mask clear
(and one that's probably fogging up),
panic-breathing a soggy SCUBA reg and dealing
with the thermal shock of sudden immersion
are likely to cause death by drowning much
earlier. Don't underestimate the thermal
shock and how useless it makes you with no
exposure suit. Breathing a regulator without
a mask is a skill in itself. You're probably
already suffering from fatigue, stress, high
CO2 and/or low O2 from waiting for rescue and
getting to such a desperate point. All of
these cause significant mental impairment
before you even start on the escape.
Forget about planning to hold stops on the
way up, switch gases or do decompression.
Even if you're lucky enough to still be
conscious and thinking in the latter stages
of the rapid ascent, personal buoyancy
control is unlikely to be possible.
So if you're going to attempt to escape, I
suggest the best chance for survival is to
plan on a very simple setup (per person),
buoyancy for a rapid/undignified ascent, and
needing urgent medical attention and oxygen
on the surface. Maybe carry a cylinder of
trimix on board to give yourself a better
chance of being able to think, but it's a big
weight/cost premium if it's enough to be
useful. Use a divers (with closed bottom)
"lift bag" and a loop around at the armpits
as a quick and easy way to get a person
shooting upwards. CO2 inflatable life jacket
to keep unconscious head above water on
surface. (Inflate at depth while conscious -
won't fill much, but will expand on way up)
Might be better put towards things like extra
life support duration. Consider doing
regular practise drills that are as realistic
as possible.
Highly skilled divers mess up basic skills in
stressful situations and die with sad
regularity. Don't imagine your (and
passengers) chances of winging it at depth
will be anything other than tiny. 30m/90ft
and shallower they are a bit better.
I hate to be negative, but perhaps for deep
PSUB diving, the inability to escape is just
one of those residual risks that can be
accepted for a recreational activity.
Cheers,
Steve Fordyce
Melbourne, Australia
On Wed, 24 Apr 2019 10:57 hank pronk via
Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
wrote:
I think all submarines should have an
escape pod or jettisoning occupant sphere.
I admit I made a mistake with my escape pod
by making it only for one. An easy fix
that I will likely tackle, and that is to
stretch the pod making it big enough for
two. E3000 has a jettisoning occupant
sphere.
Hank
On Tuesday, April 23, 2019, 5:39:01 PM MDT,
TOM WHENT via Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
wrote:
A compact bail out rebreather might be the
most surviveable solution however it would
require a significant commitment in
training, maintenance as well as the cost
of the equipment itself. I personally have
not been following the development of
bailout rebreathers, although i'm aware
that some are working on this. My dive
group relies on planning for open circuit
bailout in the event of rebreather failure.
If money is no object, I am partial to the
ISC Megalodon classic CCR. In terms of
robustness and deep water capability, you
will find none better.
It will get you home and flies itself. It
is an electronic CCR which maintains PPO2
for the user. This is the unit I dive
myself and feel very confident in.
KISS classics, which are a simple and
reliable mechanical CCR apparatus, often
come up on the used market in affordable
price ranges.
Both would require significant equipment
specific training but would get you out of
a 400 ft jam with only two small cylinders
and gas to spare. CCR duration is driven by
metabolic rate and is the same irrespective
of operational depth. Even the lowest end
units will give you an hour plus.
On ascent, rebreathers do require the diver
to be monitoring the oxygen level display
in the breathing loop and very likely
adding oxygen manually - particularly in
the mCCR type on a fast ascent.
The other benefit of this setup is that an
air cell for buoyancy can be integrated
easily in one compact package.
It sounds like a lot of effort for the non
diver, but it is a functional answer to the
risks of a sub disabled in deep water.
What is a life worth?
How much risk can one accept for a hobby?
Food for thought anyhow.
Get Outlook for Android
<https://aka.ms/ghei36>
On Tue, Apr 23, 2019 at 7:34 PM -0400,
"Alan via Personal_Submersibles" <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
wrote:
As an alternative to possible death or even
worse, the loss of your submarine,
I am in early stages of designing a buoy
release mechanism that is used
for surfacing safely but has an emergency
beacon that can be activated
with an electro magnet.
Thoughts are to use 150 lb braid with a
tensioning mechanism & have an
automatic boat latch mechanism that can
slide down the braid but is fixed
to the buoy with instructions, "tie a long
rope to the ring & let down untill
latch attaches to submarine. Pull up"
The automatic latch is a device that Phil
described & provided a drawing for,
but there may be a cheap & suitable
automatic boat latch ( used on release
& retrieve on boat launching) on the
market. I am still searching & if anyone
knows of one that may be suitable I would
be interested.
Alan
On 24/04/2019, at 10:51 AM, Sean T.
Stevenson via Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
wrote:
There is a significant difference
between submarine escape and a planned
SCUBA dive with regard to both the dive
profile and the equipment that you can
reasonably carry. An escape is more
akin to what is known as a buoyant
emergency ascent in recreational
diving, where you need to get to the
surface yesterday and all other
considerations are secondary. In this
specific case, trying to keep to a slow
ascent rate would significantly
increase the incurred decompression
obligation that you must necessarily
then blow off as you ascend through the
shallows, introducing an even greater
risk. You also have the hypothermia
issue to deal with if you are not
equipped with exposure protection
specifically intended for submersion at
depth. Being cold reduces decompression
effectiveness. In order to keep to a
target ascent rate or perform
decompression stops, you would need
diving instrumentation (depth gauge and
timer), would need the skills and
experience to perform gas switches and
hold stops, and would need
significantly more bulky equipment to
have enough gas to perform a proper
decompression (slow ascent, gas
switches, etc.).
When I dive to these depths on SCUBA, I
wear twin cylinders (>100 cu. ft. each)
on my back with the bottom gas (10/70
or whatever for the planned depth and
time), plus three or four off-board
cylinders (80s) carrying the
decompression gases (typically 21/35,
35/25, EAN50 and oxygen), plus a small
bottle of argon for drysuit inflation.
Obviously, as an escapee you are not so
equipped. Far better to lockout as
quickly as possible and rapidly ascend
(with buoyant assist) to get clear of
those depths where you are ongassing
the most, and if at all possible, to
slow the ascent as you approach the
surface, and then have your surface
support or emergency responders
administer oxygen as transport is
arranged to recompression. To be
clear, an emergency escape from a
disabled submarine at these depths is
not even remotely a good idea - it is
simply a marginally better idea than
dying on the bottom.
To illustrate, if you were to attempt a
continuous ascent from 300 fsw, the
average depth is 150 fsw, which is
about 5.5 atmospheres absolute. If you
assume a surface air consumption rate
of 1 cu. ft. / minute (high, but
typical of a diver who is stressed or
working hard, which is inevitable in a
submarine escape scenario), that
corresponds to 5.5 cu. ft. / min at the
average depth of the ascent. At a 30
ft/min ascent rate, that's 10 minutes,
or 55 cu. ft. of gas consumed just for
the continuous ascent with no
decompression stops, without
consideration for the gas consumed
while blowing down and locking out.
You can judge for yourself the
practicality of carrying an 80 on a
PSub sized vessel just for emergency
escape purposes.
Sean
‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Tuesday, April 23, 2019 12:32 PM,
David Colombo via Personal_Submersibles
<personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org>
> wrote:
Hi Guys, This topic is fascinating
and scary at the same time. Accent
rates form the old Navy logs had
60ft / minute max with a
recommended max accent rate of 30
ft/ min. At 300ft escape depth,
what volume of mixed gases would
you need for a 10 minute accent
assuming you choose not to swim
60ft/min.
Best Regards,
David Colombo
804 College Ave
Santa Rosa, CA. 95404
(707) 536-1424
www.SeaQuestor.com
<http://www.SeaQuestor.com>
_______________________________________________
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<http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles>
As an alternative to possible death or even
worse, the loss of your submarine,
I am in early stages of designing a buoy
release mechanism that is used
for surfacing safely but has an emergency
beacon that can be activated
with an electro magnet.
Thoughts are to use 150 lb braid with a
tensioning mechanism & have an
automatic boat latch mechanism that can
slide down the braid but is fixed
to the buoy with instructions, "tie a long
rope to the ring & let down untill
latch attaches to submarine. Pull up"
The automatic latch is a device that Phil
described & provided a drawing for,
but there may be a cheap & suitable
automatic boat latch ( used on release
& retrieve on boat launching) on the
market. I am still searching & if anyone
knows of one that may be suitable I would
be interested.
Alan
On 24/04/2019, at 10:51 AM, Sean T.
Stevenson via Personal_Submersibles <
personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org> >
wrote:
There is a significant difference
between submarine escape and a planned
SCUBA dive with regard to both the dive
profile and the equipment that you can
reasonably carry. An escape is more
akin to what is known as a buoyant
emergency ascent in recreational
diving, where you need to get to the
surface yesterday and all other
considerations are secondary. In this
specific case, trying to keep to a slow
ascent rate would significantly
increase the incurred decompression
obligation that you must necessarily
then blow off as you ascend through the
shallows, introducing an even greater
risk. You also have the hypothermia
issue to deal with if you are not
equipped with exposure protection
specifically intended for submersion at
depth. Being cold reduces decompression
effectiveness. In order to keep to a
target ascent rate or perform
decompression stops, you would need
diving instrumentation (depth gauge and
timer), would need the skills and
experience to perform gas switches and
hold stops, and would need
significantly more bulky equipment to
have enough gas to perform a proper
decompression (slow ascent, gas
switches, etc.).
When I dive to these depths on SCUBA, I
wear twin cylinders (>100 cu. ft. each)
on my back with the bottom gas (10/70
or whatever for the planned depth and
time), plus three or four off-board
cylinders (80s) carrying the
decompression gases (typically 21/35,
35/25, EAN50 and oxygen), plus a small
bottle of argon for drysuit inflation.
Obviously, as an escapee you are not so
equipped. Far better to lockout as
quickly as possible and rapidly ascend
(with buoyant assist) to get clear of
those depths where you are ongassing
the most, and if at all possible, to
slow the ascent as you approach the
surface, and then have your surface
support or emergency responders
administer oxygen as transport is
arranged to recompression. To be
clear, an emergency escape from a
disabled submarine at these depths is
not even remotely a good idea - it is
simply a marginally better idea than
dying on the bottom.
To illustrate, if you were to attempt a
continuous ascent from 300 fsw, the
average depth is 150 fsw, which is
about 5.5 atmospheres absolute. If you
assume a surface air consumption rate
of 1 cu. ft. / minute (high, but
typical of a diver who is stressed or
working hard, which is inevitable in a
submarine escape scenario), that
corresponds to 5.5 cu. ft. / min at the
average depth of the ascent. At a 30
ft/min ascent rate, that's 10 minutes,
or 55 cu. ft. of gas consumed just for
the continuous ascent with no
decompression stops, without
consideration for the gas consumed
while blowing down and locking out.
You can judge for yourself the
practicality of carrying an 80 on a
PSub sized vessel just for emergency
escape purposes.
Sean
‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Tuesday, April 23, 2019 12:32 PM,
David Colombo via Personal_Submersibles
<personal_submersibles at psubs.org
<mailto:personal_submersibles at psubs.org>
> wrote:
Hi Guys, This topic is fascinating
and scary at the same time. Accent
rates form the old Navy logs had
60ft / minute max with a
recommended max accent rate of 30
ft/ min. At 300ft escape depth,
what volume of mixed gases would
you need for a 10 minute accent
assuming you choose not to swim
60ft/min.
Best Regards,
David Colombo
804 College Ave
Santa Rosa, CA. 95404
(707) 536-1424
www.SeaQuestor.com
<http://www.SeaQuestor.com>
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