The Octopus Conundrum

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Okay Dumpster, lol. I am kind of tired. It was a long day, wind picked up on my bike ride and then I had a to share a swim lane with Shamu.

Well, I am not going to try and answer all of that anyways.

I think you misunderstand the 60 feet thing. It is not a 58 feet vs 61 feet. It is how I feel about the dive, the conditions, my familairity with the site etc. The 60 feet is my Rubicon, a point of increasing odds being against me. The percentages begin to flip and the 60 feet is my working free dive depth, that is where it comes from. I may choose 0 feet or 80 feet on a particular day. But 60 feet is the flipping point, the seesaw of odds tips against me. Perhaps Niki Lauda, riding in the car driving like a grandpa, the lady he was trying to impress, why you cannot possibly be a F1 driver! He asked her why and she said because you drive so slow and cautious. He said there was simply no percentages in going faster. The faster he drove (anybody) the greater the percentage, possibility of a crash. For me, 60 feet represents that point. Above it I have a good possibility of reaching my surface redundacny, an acceptable risk. Below that depth, increasingly the risks increase and goes beyond what is acceptable to me. My Rubicon.

Which brings up the next concept, I think you fail to understand that I always have redundancy, the surface is my redundancy and I am going there right away if I do not like something.

And another, the Rule of Thirds, yes it is in the SDI course, yes it is in the book Solo Diver, yes it is something I have used, loosely applied often, my entire diving life. I am not telling you or anyone else to follow the Rule of Thirds, I do and will continue to do so.

And then, I realize that most people today are risk adverse. Zero is the risk they are happy with yet this is not achievable. I am a realist, I am not risk adverse. Safety is way over rated. Especially when it cripples us. Many of us, including me train and practice our skills. I also physically train to dive, I maintain a high level of physical fitness which I count on to balance the odds.

Finally, if you think I am cavalier, I think most who have dove with me would disagree. But it is true, I prefer simple systems and ultimately, I count on me, not equipment to save my bacon. And sometimes that mean me not doing the dive or at least in the way I first thought to do it.

Oh, tank size, my air consumption, it is quite low, I workout, I am an endurance athlete of sorts, amateur for sure but all my life I have swam, biked, run and it has had benefits above and beyond my waist size. I use very little air, it is simple fact. There are people I know who use even less, some of my vintage buddies are among them. Perhaps I imagine yourself as well. A tank only needs to hold enough air to complete the dive with acceptable reserves. You seem to be fixating on the 63cf tank I enjoy for beach diving solo. If it is enough, it is enough, I cannot say it more simply and for me, even at considerable depth, it is enough as long as I can do the dive and have acceptable reserves. When it is not, I go bigger. It is part of planning the dive. A novel concept, I plan my dives and I usually have a Plan B, my escape, bail out plan.

My OP was multifaceted and my main questions have probably been answered. I was interested in the increase in failure risks represented by Air II type inflator mechanisms. My other question, if not expressed clearly, along the way, I admit, is I wondered how many continue to use a standard rig/octopus (secondary on a single first stage etc) even though they are solo. It seems to have been answered, only me and Akimbo actually rig for solo. LOL.

Okay, sleepy time.

James
 
.... I wondered how many continue to use a standard rig/octopus (secondary on a single first stage etc) even though they are solo. It seems to have been answered, only me and Akimbo actually rig for solo. ...
Solo in what conditions?

We all come with our biases based on how WE dive. I need two secondaries that can be shut down independently to feel reasonably comfortable in cold water. The surface at 60' is one thing in warm clear water and quite another in ice cold green water when you are overlong for your next breath. The only real threat of adding a second secondary is a low pressure hose exploding. I'll take that chance.

This discussion seems to be complicated octo, pony, and a second standard reg. I just want two secondaries, the one I breathe and an independent "go to". A single secondary on a cylinder and a pony is true redundancy, works for me. So does an H valve and no pony. Either way I can resolve a free-flow.

And yeah, lose the long hose on solo. But again, things depend on the situation. Wookie puts people into the water and seems to feel some level of concern as to recovering all of them. Diving solo with a long hose speaks to that concern...
 
In the 70's and early 80's, all I dove with was a steel 72 on a harness..no bc, and a single reg.....Anyone good enough to be a dive buddy, could SHARE air with a single reg, easily. The whole DIR issue for the long hose and necklace reg, was for serious penetration diving, where a team is looking to optimize procedures for accidents/failure that could occur during such a penetration, OR, in a tech dive where a valve or reg failure cause an OOA scenario for a buddy, the donated long hose would make the long deco much easier --pretty much like a Hooka dive :)

If I am diving with my tech buddy Bill Mee, or my wife Sandra, in a recreational dive of 140 feet deep or less, there is no dive site I could imagine doing our video or photography in, where we could not easily do this dive in complete safety, using a single tank, a harness, and a single reg for each person. This can be so streamlined, that the kick and glide ease and efficiency, make the diver feel more like a dolphin than a scuba diver. Normally I dive DIR....and normally in our recreational dives, there are other divers around us, and I typically feel a responsibility to be an "easy reg donation source" if some "unknown diver" from our charter boat has a problem--a person that may well not have air share skills with a single reg.

Also, even though I am a DIR diver, when I am on a Video "Mission", Sandra and Bill are the real buddy team....and I am Solo with them.....I have to cover too much ground for them to follow me closely, and there are too many shots I want that require warp speed to get to....my thing, not theirs.... So I will go off Solo for a few minutes, knowing that Bill has Sandra's back....and that anything that happens in this depth range with my gear, is a non-event for me, whether I am close to my buddies or far enough away to be solo. If we are doing a 200 foot deep tech dive, I am exclusively a DIR buddy, with no solo excursions. This is even true on our 140 foot Hole in the Wall dive off Jupiter....where my responsibility to my buddies is higher.


As for myself, back in the 70's I used to practice free emergency ascents from time to time...and found 100 foot free ascents to be incredibly easy to perform....Your lungs are like an air manufacturing plant, and the constant exhale is easy to accomplish, yet you really don't feel like you have any need to breathe air in within the time it takes to reach the surface. Of course, this free ascent was easy in a time and place where the diver was streamlined....But even today, an exhale into the bc inflator, will cause the bubble in a BC to grow quickly, delivering a rapid ascent after just 15 feet of swimming or so.... In any event, if the solo diver has freediving skills, and has practiced the free emergency ascents, the small chance of a reg failure should not feel like much of a problem. Personally I would not consider the extra drag of a pony.....the only use I would have for a pony, is for 100% O2 if I needed it for a 20 foot deco stop after a deep dive ( a different issue all together).
Many today are uncomfortable practicing a free emergency ascent....for some people they may be dangerous, as some people bubble more than others.....I don't have the issue, so for me it was not a problem...but the way to practice this, is at the beginning of a 100 foot dive, before you have any significant saturation.....do the free ascent---if you are nervous, keep the reg in your mouth but don't inhale--simulate zero air in tank. Know that in a typical OOA scenario, by the time you reach 30 feet from 100, there will often be another breath or two in the reg all of a sudden :) So the idea of keeping the reg in your mouth is not a bad idea. Hmmm or make the noise if this helps you....for me just exhaling softly the whole way was quite enough. If you are a diver covered in high drag gear, this may not work for you....if you are fairly slick, and have done at least a little freediving,, this should be easy enough.....knowing how far you can easily swim on one breath, makes it feel very non-threatening to find your self exhaling to the surface for a distance shorter than you can cover on a breath ( a 60 foot freedive drop, is much more challenging than a 120 foot free ascent). Swim speed from 100 feet to the surface is not a sprint--it is a freediving cruising pace, something you would use to swim 60 feet or so horizontally.....you want to ascend much faster than the little bubbles....more of a 100 foot per minute ascent, or faster if this is easy for you. When you are at 100 feet an OOA, DCS does not exist in your world...only getting to the surface exists.
At the surface, the simulation is over, and you immediately go right back down.....With air or nitrox, you have 2 to 4 minutes before any supersaturation can occur, so if you dump your bc and swim right back down to 100 feet, you can't have an issue with DCS any way...Even if you somehow managed to bubble a bit, the bubbles should recompress, and you will do a slow ascent and stop at end of dive. If you are really paranoid about your potential for bubbling, have a friend on the dive with a pony full of 100% O2, and suck this down at 20 feet for your safety stop at dive end. At least you will KNOW the ease with which you can get to the surface on your own, from a given recreational depth. If you find you CANT do 100, and you are a solo diver, then I suppose you DO need a pony, slung stage style. So much for being slick though, and enjoying "Kick and Glide" for efficiency.
 
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BTW, if you can breath from your primary, so can someone else.

Nope. My hose is so short that we would be glued together for that to work - and I mean joined belly to belly.

See, travel with a pony, well, it is hard enough getting some place much less with a tank in your bags.

I don't own/carry a pony since I fly everywhere. So that's not an option for me.

What??? I always travel with my pony. Most often a 13cf but if I want to I can bring my 27cf and never had a problem. I just pack them in my checked bag with the valve removed along with a copy of the TSA regs on compressed air bottles. I screw in the valve when I get there and get a fill and I'm good for the duration of the trip.
 
Oh, tank size, my air consumption, it is quite low...

Hi James, just out of interest, what is you SRMV? I consider mine reasonably low, at 0.35 cu ft/min, but would not generally dive with a mini-tank, as I appreciate my bottom time so much. I solo with a 19 cu ft pony, enough for me for all recreational depths. I often do not take my pony for dives above 60 ft.
 
I took my octopus off a long time ago, I almost always dive with a pony. If I am diving solo which I do a lot the pony is my redundant air source and if I am diving with a buddy it is their redundant air source, if I deploy the pony I (we) surface, the dive is over.
Nemrod, I hope this answered your question.
 
Don't you find that Air2's drag on the bottom if you need to be close to the bottom?

If I am that low trying to reach under something or getting a good photo shot - I find my pony drags first then the Air 2 might hit...
 

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