[PSUBS-MAILIST] onboard gear
Cliff Redus via Personal_Submersibles
personal_submersibles at psubs.org
Wed May 1 09:50:31 EDT 2019
Carsten, I concur.
Cliff
On Wednesday, May 1, 2019, 8:34:14 AM CDT, MerlinSub at t-online.de via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
Alan, you are right, today the military submariener use escape suits to give them termal protection.
The simple reson is that the may wait long on the surface.
If you have a spaceíous submarine - you can storage dry or wet divers suit
there- but for the most 1-3 person subs that is no option.
On Sgt.Peppers even a Steinke Hoods was no option.
But if this is no option because the lack of space - delete it from the list.
So what can stay?
- Old Steinke hoods,
- new BCD and
- normal dive gear.
- Relaseable dome as Breathing parachute
Normal dive gear give you no extra lift - which is the most important factor to
prevent longer breathing in the depth and get decommprsion thickness.
The recommdation of the old video are for military submarines which have a LP hose and a exit chamber.
In a small Psub I would wear the Steinke hood. Breathing with the snorckel valve of the hood from the inside of the submarine.
Flood and compress the sub. Inflate the hood by LP hose or if not available do the job via the inflator hose.
Using the inflator hose is secondary -better use the LP hose if availabe. If you have to use the inflator tube this means
to open the zipper of the hood - which is on such a old device a risk on its own.
I fogot to mention that on our Steinke hoods we not only rebuild the neck scirt,
we also exchange the inflator adapter from the militar one to a scua diver LP connector.
https://www.youtube.com/watch?v=kdIleUORf0I
On 0:40 you can see how much force air and water did to your head. Even a divers mask can easy fly away. (See at 3:;00)
But a Steinke Hood gives your head some protection.
On 1:42 you can see the me useing a divers old style BCD. And yes I breathe from the unit and I am still fine. :-)
Another BCD exit.
https://www.youtube.com/watch?v=mKe76HRVPSQ
And the same with a Steinke Hood
https://www.youtube.com/watch?v=gtQ3HNuxcGA
But again- in my option the best idear to survife such a event is a training and a divers course.
By the way if you have issue idears about bacteria etc. in your BDC.
After such an event the police will carry you regular anyway to a hospital.
Bring the BCD with you and give it to the doctors - they can easy check out
if it was something in which is not good for your healty..
vbr Carsten
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Betreff: Re: [PSUBS-MAILIST] onboard gear
Datum: 2019-05-01T12:45:45+0200
Von: "Alan via Personal_Submersibles" <personal_submersibles at psubs.org>
An: "Personal Submersibles General Discussion" <personal_submersibles at psubs.org>
The Steinke hood might be alright for getting out of a submarine with assistance from one or two hundred feet, but would be not so good for a psubber trappedbelow that. As the escape video says, you need to equalise by pinching your nose before you put the hood on. So you would be trying to put the hood on at the point that your sub is equalised. This would require accurately comparing externalpressure with internal pressure. If you put it on too soon you wouldn't be ableto equalise & may need to take it off to re-try equalising, or burst your ear drums. If you put it on too late the hatch may open with a forceful entry of water & exiting of air.You would be required to do this while under the influence of nitrogen narcosis& I think somewhere around 350 ft you are so narked that you couldn't get out.You are relying on breathing expanding air from the jacket but there would bevery little air expansion from say 400ft to 200ft; about 1 litre from a 14 litre capacitySteinke hood. Relaxed breathing is about 6 litres a minute.Quote from an article on Steinke hoods....As early as 1974, one study highlighted significant biomedical shortcomings in the escape system: hypothermia, nitrogen narcosis, hypercarbia, barotrauma, and decompression sickness. These shortcomings were attributed to the method of escape and operating procedures. Furthermore, the current method of submarine escape was no longer practical, because the Steinke Hood provided no thermal protection for the escaper during the escape and while awaiting recovery. Accordingly, citing emerging technology and recent studies, by 1996 researchers at the Naval Submarine Medical Research Lab presented biomedical-based recommendations for enhancing survival of escapers by a) overhauling current submarine escape systems and procedures and b) substituting existing thermal protection suits for the Steinke Hood.Alan
On 1/05/2019, at 9:03 PM, MerlinSub at t-online.de via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
Really good training video. Shall safe to the Psubs server..
I have 5 or so devices for the Euronaut. Pretty old USNavy devices form the 80ies and far over it expected lifetime.
But it was nessesary to renew the neck scirt. Was pretty hard. Any small diver suit maker or reair company can do these job.
We let them make new scirts from Neopren. 50 USD or so each. Replacement comes without a neck hole
from the suit repair company. We make the holes ourself according to the smallest crew member neck.
In case you have no LP hose access you can fill the unit with the small inflatour mouse tube.
This is clear opposite to the instruction video - but better than to lost your life.
No.6 unit on board has a blue mark on his bag - it is our training device o teach new crew members.
The other ones are sealed.
I think you can may convert a new divers vest BCD into such a device.80% of the device is allready on a BCD.
Show the video to a diver suit repair company and give them the new BCD to convert is may an idear.
The unit with a small air pony bottle as the mmost BCD have - will be a great update- no need of a LP Hose anymore.
If some of your guys try so for such a conversion - give the comunity here a call
- may it will be cheaper if you can convet a bunch.
vbr Carsten
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Betreff: Re: [PSUBS-MAILIST] onboard gear
Datum: 2019-04-30T23:09:56+0200
Von: "Cliff Redus via Personal_Submersibles" <personal_submersibles at psubs.org>
An: "Personal Submersibles General Discussion" <personal_submersibles at psubs.org>
If you have not had a chance to see this old US Navy training film on submarine escape, you might want enjoy this. https://www.youtube.com/watch?v=ffOJEJwWSbs The training is on using the Steinke Hood. I use this appliance on my boat. Even though it is getting harder to find this hoods, they surface on Ebay periodically. Cliff On Saturday, April 27, 2019, 9:11:53 AM CDT, 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.
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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 thegas would be expanding very little over the first few hundred feet & as yousay 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
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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 goodpractice because of disinfectants used to clean out BCDs. You would needto 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 thevolume of your sub, how quickly you can flood it, how quickly you can equaliseyour ears & what mixed gas you need to avoid getting narced, bent & O2Poisoning. 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 mixedgas 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 toact as a reserve ballast blow so it is not wasted. Leave the sub with the ponybottle full of mixed gas & inflate the horseshoe BCD with it, then breath fromthe 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 sometime while the submarine fills with water & equalises. So the extra 15 secondsgrabbing 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 tofeel 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 wouldbe an asset. Pitty to burst your ear drums when you might be doing a simpleescape from 100ft.As Emile & Carsten showed with their practice escapes; they could get outrelatively easily, & with a bit of air ( 6 cu ft pony bottle ) you could get to thesurface easy enough.If I were escaping from deeper I would use a pony bottle with mixed gas sometime 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 surfacemaking stops if I felt able.There is sense in you saying Keep It Simple, but if you pre plan & practice, amore 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 equalisefor 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 shoeBCD as a life jacked. A bit clutsy getting in to the sub wearing a BCD & largetank. They make a 6 cu ft pony bottle but I would have to import it & it wouldonly 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 thata hose attaches to for use as a reserve ballast blow. So you breath through your pony reg while flooding & escaping, then whenoutside use the 80 cu ft tank reg while detaching the ballast hose, attachingthe BCD connection and un latching the tank.It could be practiced in the garage with your eyes closed & done in about 15seconds. 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 a13 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 emergencyyou could breath expanding air out of the BCD through the manual inflationmouth piece. With a BCD as apposed to a life jacket you have the chance toslow 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 besitting 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 moreprobability that entanglements like ropes & nets are going to be encounteredIn shallower depths. BTW the pressure in the sub is going to increase incrementally quicker as itfloods & you need to keep equalising your ears like mad toward the end oryou'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.
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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 usedfor 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 anautomatic boat latch mechanism that can slide down the braid but is fixedto the buoy with instructions, "tie a long rope to the ring & let down untilllatch 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 anyoneknows 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 Colombo804 College AveSanta Rosa, CA. 95404(707) 536-1424www.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 usedfor 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 anautomatic boat latch mechanism that can slide down the braid but is fixedto the buoy with instructions, "tie a long rope to the ring & let down untilllatch 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 anyoneknows 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 Colombo804 College AveSanta Rosa, CA. 95404(707) 536-1424www.SeaQuestor.com
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Carsten,yes you could rely on air out of your BCD but it is not regarded as a goodpractice because of disinfectants used to clean out BCDs. You would needto 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 thevolume of your sub, how quickly you can flood it, how quickly you can equaliseyour ears & what mixed gas you need to avoid getting narced, bent & O2Poisoning. 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 mixedgas 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 toact as a reserve ballast blow so it is not wasted. Leave the sub with the ponybottle full of mixed gas & inflate the horseshoe BCD with it, then breath fromthe 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 sometime while the submarine fills with water & equalises. So the extra 15 secondsgrabbing 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 tofeel 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 wouldbe an asset. Pitty to burst your ear drums when you might be doing a simpleescape from 100ft.As Emile & Carsten showed with their practice escapes; they could get outrelatively easily, & with a bit of air ( 6 cu ft pony bottle ) you could get to thesurface easy enough.If I were escaping from deeper I would use a pony bottle with mixed gas sometime 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 surfacemaking stops if I felt able.There is sense in you saying Keep It Simple, but if you pre plan & practice, amore 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 equalisefor 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 shoeBCD as a life jacked. A bit clutsy getting in to the sub wearing a BCD & largetank. They make a 6 cu ft pony bottle but I would have to import it & it wouldonly 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 thata hose attaches to for use as a reserve ballast blow. So you breath through your pony reg while flooding & escaping, then whenoutside use the 80 cu ft tank reg while detaching the ballast hose, attachingthe BCD connection and un latching the tank.It could be practiced in the garage with your eyes closed & done in about 15seconds. 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 a13 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 emergencyyou could breath expanding air out of the BCD through the manual inflationmouth piece. With a BCD as apposed to a life jacket you have the chance toslow 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 besitting 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 moreprobability that entanglements like ropes & nets are going to be encounteredIn shallower depths. BTW the pressure in the sub is going to increase incrementally quicker as itfloods & you need to keep equalising your ears like mad toward the end oryou'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.
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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 usedfor 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 anautomatic boat latch mechanism that can slide down the braid but is fixedto the buoy with instructions, "tie a long rope to the ring & let down untilllatch 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 anyoneknows 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 Colombo804 College AveSanta Rosa, CA. 95404(707) 536-1424www.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 usedfor 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 anautomatic boat latch mechanism that can slide down the braid but is fixedto the buoy with instructions, "tie a long rope to the ring & let down untilllatch 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 anyoneknows 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 Colombo804 College AveSanta Rosa, CA. 95404(707) 536-1424www.SeaQuestor.com
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