Pony Bottle

[DevonDiver]

That is an interesting twist. Isn't a 'thinking diver' supposed to consider (or mull over, or theorize, etc.) scenarios as part of mental prep to dive?

While I strongly believe in "Learn from other's mistakes; you don't have time to make them all yourself", I also don't know what I don't know, and a fully redundant backup is a good safety. However, there are far too many people happy with the way they carry it to say that any one way is 'better', just that the way it is carried is suitable for the diver concerned.

Just because the majority 'like' it, does it make it best? Quite often, it is the opposite.

Don't get me wrong...I am not arguing this either way. I just champion that people have really debated the pros and cons to any particular configuration....and have based a decision on evidence, rather than hypothesis and speculation.

I started out diving with a cylinder-mounted pony. I only really needed it once. With hindsight, I think I would have prefered to have had it slung during that emergency.

I also know of a diver who died (Plymouth, UK) because of incorrect use of a pony. I am pretty certain that he wouldn't have died if he had used a slung cylinder.

 

[Jax]

I also know of a diver who died (Plymouth, UK) because of incorrect use of a pony. I am pretty certain that he wouldn't have died if he had used a slung cylinder.

:shocked2: What happened? That sounds like a lesson to learn . . .

 

[DevonDiver]

I heard the guy jumped in and descended to 26m whilst breathing accidentally from his pony. It depleted quickly, left him OOA. Panic. Solitary ascent. Dead.

The true lesson is: never underestimate how easy it is to screw up...and how lethal even a simple mistake can be.

 

[Jax]

Uh . . . yeah. Thank you.

 

[Cave Diver]

This is a good example of why it can be important to accept that others may have specific relevant experience.

Theorising about emergency scenarios is a flawed technique. There are enough real-life learning experiences within the diving community to share and develop from.

That is an interesting twist. Isn't a 'thinking diver' supposed to consider (or mull over, or theorize, etc.) scenarios as part of mental prep to dive?

While I strongly believe in "Learn from other's mistakes; you don't have time to make them all yourself", I also don't know what I don't know, and a fully redundant backup is a good safety. However, there are far too many people happy with the way they carry it to say that any one way is 'better', just that the way it is carried is suitable for the diver concerned.

The truth lies somewhere in the middle. It is good to theorize about potential issues and the responses to them. But at the same time, you shouldn't discount the real life experience of others just because you've theorized something.

This saying comes to mind: "In theory there’s no difference between theory and practice. In practice there is."

 

[Cute Teddy]

ok guys and JAX thanks for all the inputs & your valuable time to share your views with me
pppppppppppppppppppppppplllllllleeeeeeeeeeeeaaaaaaaaaaaaaaaassssssssssssseeeeeee..
Dont get personal be professional....

Well i guess i will be mounting it on the tank initially why i thought to do like this is because

IF MY MAIN TANK FIRST STAGE FREE FLOWS I WOULDNT KNOW IT & cannot do annything about it..right...??..i mean a minor trickle ok..so what diffrence it make on a PONY...ya i can shut it down if SLUNG...any full blown free flow from main first stage mean air share or PONY right..if this happen to PONY i simply abort and go up.. so i thought of configuring like this

A SPG on my R/H side on a suitable length of hose so it can be checked easily..
The 2nd stage from the PONY on a yellow hose of approprate length & not using any OCTO.from my main tank ist stage.

Will this config be a problem since we are talking recreational depths MAX 40m on single tanks...????

Your help & Comments welcome

 

[Cave Diver]

ok guys and JAX thanks for all the inputs & your valuable time to share your views with me
pppppppppppppppppppppppplllllllleeeeeeeeeeeeaaaaaaaaaaaaaaaassssssssssssseeeeeee..
Dont get personal be professional....

Well i guess i will be mounting it on the tank initially why i thought to do like this is because

IF MY MAIN TANK FIRST STAGE FREE FLOWS I WOULDNT KNOW IT & cannot do annything about it..right...??..i mean a minor trickle ok..so what diffrence it make on a PONY...ya i can shut it down if SLUNG...any full blown free flow from main first stage mean air share or PONY right..if this happen to PONY i simply abort and go up.. so i thought of configuring like this

A SPG on my R/H side on a suitable length of hose so it can be checked easily..
The 2nd stage from the PONY on a yellow hose of approprate length & not using any OCTO.from my main tank ist stage.

Will this config be a problem since we are talking recreational depths MAX 40m on single tanks...????

Your help & Comments welcome

The best advice I can give you is to figure out what issue you're trying to solve, look at the various ways it can be accomplished and then weigh the pros and cons of each.

I'll throw a scenario at you:

I want a pony bottle because I'm concerned about something happening, causing me to run out of air.

Possible Solutions:

1) Carry a pony bottle, just in case.
2) Dive with a reliable buddy you can share air with
3) Make a solid dive plan, including gas reserves and stick with it.


In my opinion the best options are #2 and #3 and they are also good diving habits. But assuming you want to go with a pony bottle, for your own peace of mind, things you need to consider are:

Mount it or sling it? Valve on or off? If you mount it what are the pros and cons? Can you reach the valve? Can you read the SPG? Can you pass it off to another diver? If you dive with the valve on, is there a possibility of a leak or free flow? If you dive with it off, is there a possibility you can't reach it?

There are dozens of questions and answers to be considered in order to come to an informed decision. You really need to weigh the options of each and figure out what's right for you.

If you want the best view, stand on the shoulders of the giants who came before you.

 

[Crush]

IF MY MAIN TANK FIRST STAGE FREE FLOWS I WOULDNT KNOW IT & cannot do annything about it..right...??..i mean a minor trickle ok..so what diffrence it make on a PONY...ya i can shut it down if SLUNG...any full blown free flow from main first stage mean air share or PONY right..if this happen to PONY i simply abort and go up.. so i thought of configuring like this

I will attempt to stay on topic this time. Since you asked about free-flow, here is some advice on avoiding or dealing with cold-induced free-flow: http://www.scubaboard.com/forums/basic-scuba-discussions/350887-free-flow-what-do.html

In summary, in general if you get a free-flow the easiest thing to do is call the dive. This assumes that you can ascend to the surface unimpeded. Breathe off the flowing reg - do not switch to your octo or backup air. If you are diving doubles you can try to save the dive by isolating the flowing valve and letting it thaw in the water. This can in theory be done with a pony but that would be my last choice since the pony has very little extra air - it is a bail-out device IMO.

A free-flow in your first or second stages will result in air bubbling from your secondary reg when there is no "demand" for it. Put another way, if your first stage free-flows you will know it. All of my free-flows have started very slowly and increased in flow rate - they have left me with ample time to ascend and in one case, even enough air do a safety stop. Keep breathing off the flowing reg - don't waste good air by switching to your octo/backup. Next time you are diving depress the purge button and breathe off it - that is what it feels like.

I have no information to back this up, but I think that most free-flows occur in the second stage. The pressure drop across the first stage is greater, resulting in larger cooling. However the air in the hose will not warm much before it hits your second stage, with a result that cooling across the second stage is essentially cumulative with the cooling across the first stage. You need ice to form for a cold-water induced free-flow, and provided that your air fills were dry, there is more likelihood of moisture in your second stage.

A SPG on my R/H side on a suitable length of hose so it can be checked easily..
The 2nd stage from the PONY on a yellow hose of approprate length & not using any OCTO.from my main tank ist stage.

I dive with a main reg and an octo from my main tank and a separate reg on the pony. The pony reg is stowed via a bungee on the pony, keeping that reg away from my main and octo, thus avoiding confusion. This is a personal choice. The reason that I opt for this setup is that if someone other than me is truly OOA early in the dive, my main tank with two divers breathing off it will last longer than a 19 cu ft pony. I have opted for a 19 cu ft pony since it offers me a rock bottom of 130 ft, including a safety stop and 1 minute at depth.

 

[DevonDiver]

A SPG on my R/H side on a suitable length of hose so it can be checked easily..
The 2nd stage from the PONY on a yellow hose of approprate length & not using any OCTO.from my main tank ist stage.

Will this config be a problem since we are talking recreational depths MAX 40m on single tanks...????

Don't rely on color coding to differentiate between regs from different gas sources.

Ideally, get a very differently shaped regulator for use with the pony, to prevent any chance of accidentally breathing of the wrong tank.

When I first started using a pony, I used to dive Apeks regs, but always used a side exhaust type regulator (dacor vyper) for my pony, so there was no chance of confusion.

You don't need an octo on your pony.

I used to wrap the pony SPG hose onto the Reg hose. Both were secured on my left harness d-ring. Easy to check the status and access the reg. Hard to confuse with my main tank Octopus, which was bungeed beneath my chin.

Slung cylinder tends to look awkward and less comfortable to newbies. It's hard to describe that it's actually more comfortable. Do perhaps a dozen dives with in both configurations and see what you think.

 

[dumpsterDiver]

ok guys and JAX thanks for all the inputs & your valuable time to share your views with me
pppppppppppppppppppppppplllllllleeeeeeeeeeeeaaaaaaaaaaaaaaaassssssssssssseeeeeee..
Dont get personal be professional....

Well i guess i will be mounting it on the tank initially why i thought to do like this is because

IF MY MAIN TANK FIRST STAGE FREE FLOWS I WOULDNT KNOW IT & cannot do annything about it..right...??..i mean a minor trickle ok..so what diffrence it make on a PONY...ya i can shut it down if SLUNG...any full blown free flow from main first stage mean air share or PONY right..if this happen to PONY i simply abort and go up.. so i thought of configuring like this

A SPG on my R/H side on a suitable length of hose so it can be checked easily..
The 2nd stage from the PONY on a yellow hose of approprate length & not using any OCTO.from my main tank ist stage.

Will this config be a problem since we are talking recreational depths MAX 40m on single tanks...????

Your help & Comments welcome

This will work fine. I personally forgo the extra pony bottle spg on a hose, because it is more gear than i want. I use a button gage and check before I go down. I hope that the air does not leak out during a dive without me noticing it.

I think a very important safety aspect is to route the pony bottle hose down and under your arm and then to a necklace on your neck. If the pony bottle second stage should start to freeflow, you will notice it around your neck, but less likley if clipped to the front of your BC. I also think it is important to do as you proposed and NOT take a third second stage (one from the primary tank) because it adds to confusion, complexity, increases the chance for confusion and also freeflow.


Using a significantly different mouth piece on the second stage of the pony bottle will probably be more effective in allowing you to distinguish the main from the pony bottle reg, than hose color because it will be under your arm anyway. If you can tell the difference in an emergency without looking, it is safer. A portion of this video (at 2:30) (Diving with my 11 yr old) you can get a look at my personal pony bottle configuration with respect to the pony bottle hose routing. (My pony hose is colored however).

http://www.youtube.com/watch?v=pjiSD0sPRIc