Is there a valid reason for a pony bottle

[caruso]

, I now carry redundant shoes with me everywhere, in case my primary shoes fail. Three is two, two is one, one is none.

Not understanding why you carry two extra shoes. One extra shoe should be more than enough, I mean what are the odds of a double shoe failure?

 

[doctormike]

Still better than tryna breath salt water.

But not as good as doing a safe ascent with your pony!

 

[doctormike]

Not understanding why you carry two extra shoes. One extra shoe should be more than enough, I mean what are the odds of a double shoe failure?

My shoes are chiral. Take a look at yours, I'll bet yours are too...

 

[Eric Sedletzky]

Hi Eric,

I respect your opinion and it is very valid, for you.

Would you dive to 200 feet on a single tank and no stage bottle?

Or, is your opinion based solely on recreational diving in benign conditions? If so, I agree with you.

I will still dive with redundant gear while agreeing with your opinion.

markm

No, I would dive to 200’ with appropriate size doubles with proper gas for that depth, stage bottles with appropriate gas, appropriate training to do such dives, the right dive plan, and a qualified and appropriate dive buddy. There would be no “pony” involved in such a dive since it would be a little pointless.
You’re right, I was referring to recreational dives and depths in regards to carrying a pony. I used to carry a pony years ago but came to the conclusion that it was clutter that was actually getting in the way and probably causing more of an entaglement hazard and something else the feather boa kelp and surf could use as a handle to have their way with me so I ditched it.
I’m using older Scubapro stuff and older Conshelf all of which I tune myself so free flows are not something I’m worried about.
As far as running OOG, no I don’t think so. That's rank amatuer crap, and any diver that fails to monitor their air supply needs remedial training as Max pointed out.
I never solo dive past a depth that I know I can make it to the surface doing a blow and go. Beyond that it’s proper gear including proper team mate.

 

[caruso]

My shoes are chiral. Take a look at yours, I'll bet yours are too...

I never knew.

That explains my foot issues I mentioned earlier.

 

[Bob DBF]

They actually wouldn't have enough gas to make it safely to the surface if they were close to NDLs. I have taken a chamber ride. I don't ever want to do that again.

Since said diver was extending his bottom time, and N2 load, on the pony and OOA for the second time in the dive I'd say he would be in a worse position on his way up. I would have tossed him off the boat permantly the first time, but I'm not Max and I can understand his solution.

Personally, I normally do not use a pony unless I am going real deep or doing something particularly, shall we say, interesting. That also includes my solo diving.

And for the record, I don't give a rats ass what others do when they rig their kit. I expect the same from others but I know it's a lot to expect, especially on the Internet.



Bob

 

[hxtk]

I plan my dives so that two simultaneous major problems won't kill me. Major problems include loss of one breathing gas, entanglement, loss of buddy, and loss of buoyancy. 2x lost breathing gas and loss of breathing gas with loss of buddy both require a pony bottle if you have any reason not to consider CESA a valid option.

If you are diving solo or with a buddy you cannot rely upon then you need to plan to solve all the problems (except loss of buddy) without them. In that case you need a pony to solve any two problems. Beyond instabuddies, the latter probably also includes several regular buddies; I know I have regular dive buddies whom I would want several more (improving) dives with before going to any significant depth and I know a couple of people have felt the same way about me (rightly so as I was even more of a novice then than I am now).

 

[doctormike]

Since said diver was extending his bottom time, and N2 load, on the pony and OOA for the second time in the dive I'd say he would be in a worse position on his way up. I would have tossed him off the boat permantly the first time, but I'm not Max and I can understand his solution.

Not sure I understand your point. Who is "said diver"?

Here is the point I was making. Figuring that you can always make it to the surface even if you have a catastrophic gas failure without a backup gas supply implies a CESA or breathing from a leaking tank as you rapidly head for the surface. That is NOT a safe, slow ascent with a safety stop. Doing a normal safe, slow ascent with a safety stop minimizes your chance of DCS. A pony bottle will let you do that.

 

[Bob DBF]

A pony bottle will let you do that.

Assuming one has not been using it for bottom gas after already running OOA on their tank as the diver on Max's boat did. If a pony is used properly it works well, if used as a stage you no longer have a pony for emergency gas, and a greater N2 load on the way up.


Bob

 

[Stoo]

If you maintain your gear properly, including inspecting hoses, watch your spg and don't dive in a way that you're too deep to make an ascent with the amount of remaining air you have, odds are that you will never have any of these issues.

Because there is not a realistic scenario possible were I will need one.

As both of you guys are based in areas where the water is cool, not cold, I'll cut you some slack....

In these parts, a catastrophic reg freeze-up is a distinct possibility for about 1/2 of the dive season, and a reasonable possibility for the rest of it. And before you dismiss this with a comment about "proper cold water regs" etc, bear in mind that I see this most often in relatively newer divers. Most of us that dive in Tobermory regularly and for an "extended season" wear doubles, or dive SM. It's not because we need the extra gas, it's because we want the redundancy of a completely separate reg and gas supply.

A pony is a simple "entry level" redundant system. When I was actively teaching, I encouraged students to include a pony and cheap, cold water reg as a "required" bit of kit.

To give you a specific example, last spring I was at one of our wreck sites, mid May. The wreck lies in 105' of water, but most of the dive would typically be conducted in 90' or so. Very much an advanced recreational dive. Water temp at the surface at the time of year is typically about 40°/4° and about the same at the bottom, although it can be as low as 37°/3° and it will never be above 42°/5° all year, other then when there's some weird current blowing through.

The morning we were there, there was a charter with I would say 8 divers on it. I didn't know them, but they were all in dry suits, so presumably "advanced" divers. Every single one of them froze up within 10 minutes of heading down. Thankfully, many freeze-ups happen on descent, when a diver makes the mistake of laying on their inflator and inhales at the same time. In those cases, typically, it's pretty simple to beat a hasty retreat to the surface. If you're watching from another boat, you can see the geyser of bubbles long before the diver rockets out of the middle of them. The odd person is completely freaked by the experience. Most are shaken. A few laugh it off, and once in a while, someone embolizes and dies. There was a 31 year old woman that embolized this spring after a freeze-up in 100'. She's been in a vegetative state ever since.

If the freeze-up occurs later in the dive, when the diver is say at 1000 psi and heading back to the upline, he's got a real problem, because that 1000 psi will blow through his regulator very quickly. Plus, he now has the added worry of a potential decompression obligation or close to it. Guaranteed their ascent rate is going to exceed 30 fpm and a safety stop isn't happening. Best case is that they have a near miss. Next best is a bend, and last, is they run out of gas in 60', panic and die. To quote our local Hyperbaric Physician, "We can fix bent. We can't fix dead."

Incidentally, when I worked in Tobermory, and before true cold water regs were really a thing (Other than the Blizzard) double fatalities were common and outnumbered singles. That was because of the proverbial "cascading events"... a freeze-up led to air-sharing which led to double freeze-ups and double embolisms. We lost 12 people in two years here. That was a long time ago, but my recollection is that ever one of them involved a freeze-up and most began with one.

Sorry for the long reply, but a pony and a second reg has the potential to end a serious event. It's not perfect, but it's a great help.

And no matter how well someone maintains their gear, a freeze-up is always possible. I had one at 170' a few years ago, and even with full redundancy in my doubles, AND a slung bottle of 50%, it's a puckering moment. It's great you can shut down one post, but if one reg freezes, the other one likely isn't too far behind, but it sure beats nothing!