[PSUBS-MAILIST] onboard gear

Sat Apr 27 18:58:53 EDT 2019

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 via
Personal_Submersibles <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>
>
> An: "Personal Submersibles General Discussion" <
> 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> 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
>
> Get Outlook for Android <https://aka.ms/ghei36>
>
>
>
> On Fri, Apr 26, 2019 at 8:14 PM -0400, "Alan via Personal_Submersibles" <
> 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 via
>> Personal_Submersibles <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>
>>
>> An: "Personal Submersibles General Discussion" <
>> 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> 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> 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> 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 via
>> Personal_Submersibles <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>
>>
>> An: "Personal Submersibles General Discussion" <
>> 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> 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> 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> 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> 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> 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> 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
>>>
>>>
>>>
>>> _______________________________________________
>>> Personal_Submersibles mailing list
>>> Personal_Submersibles at psubs.org
>>> 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> 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> 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
>>>
>>>
>>>
>>> _______________________________________________
>>> Personal_Submersibles mailing list
>>> Personal_Submersibles at psubs.org
>>> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>>>
>>> _______________________________________________
>>> Personal_Submersibles mailing list
>>> Personal_Submersibles at psubs.org
>>> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>>> _______________________________________________
>>> Personal_Submersibles mailing list
>>> Personal_Submersibles at psubs.org
>>> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>>> _______________________________________________
>>> Personal_Submersibles mailing list
>>> Personal_Submersibles at psubs.org
>>> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>>
>> _______________________________________________
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>> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>>
>>
>>
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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 via
> Personal_Submersibles <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>
>
> An: "Personal Submersibles General Discussion" <
> 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> 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> 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> 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 via
> Personal_Submersibles <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>
>
> An: "Personal Submersibles General Discussion" <
> 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> 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> 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> 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> 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> 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> 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
>>
>>
>>
>> _______________________________________________
>> Personal_Submersibles mailing list
>> Personal_Submersibles at psubs.org
>> 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> 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> 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
>>
>>
>>
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>>
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