pony bottles

[hlsooner]

Ah ScubaBoard, another day, another thread bashing pony bottle users.

 

[grassyknoll]

The most interesting thing I find in the long running pony debate is that opponents of ponys are adamant that nobody should use one, whereas I have never heard a proponent of ponys declare that everyone must use one.
I love people who think only in absolutes, I wonder if somewhere in their past one of their forefather had muttered
"Uuugh, raw meat good, Grob no need fire, fire bad, fire could hurt Grob, fire take TWO sticks to start and Grob could get burned, Grob use buddy-plan, Ooob spoon with Grob keep Grob warm, not fire".
Evolve or perish.....

 

[hlsooner]

The most interesting thing I find in the long running pony debate is that opponents of ponys are adamant that nobody should use one, whereas I have never heard a proponent of ponys declare that everyone must use one.
I love people who think only in absolutes, I wonder if somewhere in their past one of their forefather had muttered
"Uuugh, raw meat good, Grob no need fire, fire bad, fire could hurt Grob, fire take TWO sticks to start and Grob could get burned, Grob use buddy-plan, Ooob spoon with Grob keep Grob warm, not fire".
Evolve or perish.....

 

[MikeFerrara]

Ah, that explains things. I look at it from a rather different perspective.

No buddy? Well, actually, I *do* tend to get a bit of solo diving in (thoroughly understanding the risks and choosing to accept them), but even buddy diving, I often do not have the luxury of diving with an equal. I would count one of my buddies as a reliable source of assistance (redundant gas, detangling, etc), but the rest of the time, I have to choose between diving with a marginal buddy or simply not diving.

There are a ton of ways that a bad buddy can cause you problems long before gas supply becomes an issue. Diving with a bad buddy is like intentionall sabotaging your dive. Even if you can prevent them from getting you hurt, it isn't any fun to be around when they get themselves hurt either. Then of course, they can do a good job of ruining a dive without anyone getting hurt. To each their own but I would rather not dive than dive with a buddy that I felt wasn't up to the dive at hand. You can only do so many things wrong and still expect the results to be good.

Incidentally, while I have no idea if you would say so, it seems that many people think symmetric redundancy is a good thing, while asymmetric redundancy is terrible. I don't think I quite understand their perspective, or perhaps they don't understand mine, but at least I can take comfort in knowing that I have redundancy (and that asymmetric redundancy is a concept that is long established in fields other than diving).

I don't know how often that issue comes up. Redundancy on your main supply can essentially keep your gas plan valid through an equipment failure. If I do a dive where I feel the need for redundancy, I address the main supply first. Regardless of what other tanks I may carry or why, if I want redundancy, I'm going to have it on my main gas supply.

Off the top of my head I can come up with a couple of reasons for that. One, is just volume. What gives me more reserve gas, salvaging my main supply (say it's just a single 80 with an h-valve) or having to give up using my 80 to switch to a much smaller supply?

Another erason is that, if you look at how a pony is generally going to be rigged or carried it's actually MORE prone to loss or damage than the main supply so it's the one I would count on failing, or otherwise being unuseable first and therefore not a good backup.

A good example might be a dive where I want to add margine by having more reserve volume...like diving a new cave or a siphon or whatever. I'm not going to get bigger doubles. I'm going to use stages. Sort of like a pony, huh? Except, I don't breath the main supply down and save the stage (pony) for a backup. I breath the stages first and reserve my main supply. Once in a while I do a dive on stages only and never touch my main supply. Again, because the stage/pony is the one most likely to come up missing or nonfunctional...and of course the main gas supply has redundancy in the form of a manifold or an h-valve. So, if I were to carry an extra tank either for the purpose of redundancy or volume, that is actually the tank that I would start out on.

Lets go back to your comment about symetry. If a carry two single tanks equiped with single output valves, which is more likely to fail? Lets say that I carry them such that niether is at more risk than the other. ok, now one is as likely as the other to fail. I would prefer symetry here. I would not use one and save the other because I don't know which is going to blow a gasket. I would alternately use both and each would contain a portion of my reserve. Now no matter which one fails, I still have reserve in the other.

Really, on dives where we use lots of tanks it's the stage and decompression bottles that fail most often and we use the main supply as backup, not the other way around.

 

[frankc420]

I want a pony bottle for several reasons. None include me breathing off it unless it's an emergency. Diving with air hogs, you tend to run into situations you wish you weren't part of. This is where a pony comes in. Say your buddy runs out of air at 80', would you rather pass off your pony and ascend, or give him your reg and breathe off your octo which doesn't have a comfy mouthpiece! I would rather give him my pony!

First stages do seize. Second stages do hose up. Gauges do freeze. If there wasn't a place for a pony, they wouldn't exist. If you want a pony for more bottom time, that's the complete wrong reason to get it. But if you want to add a false sense of safety to a dive, a pony is a good start, IMO.

I would much rather have a frantic diver run off to the surface with my pony than with me and my reg. One hurt diver is better than two. Plus, we cannot breathe water, so what's the harm is carrying a backup!

 

[jeckyll]

Ah ScubaBoard, another day, another thread bashing pony bottle users.

From what I've seen it's more encouraging divers to think through their decisions carefully.

Bashing would be "You can lead a pony bottle diver to water, but ya can't make him think". Noone's really saying that though

(did I mention I dive with a 40 currently on deeper dives? )

Seriously though, when you compare the perceived need with the dives that are being undertaken, and then read some of the stories (back mounted pony bottle bubbling away into nothing with the diver unaware, then running out of air, switching to their pony and voila, CF) it shouldn't be hard to understand why some people here have some strong stances on the subject.

Should it?

 

[frankc420]

PS - If you dive with me and are OOA and use my pony. You will:

1. Refill it.
2. Buy my next air fill.
3. Buy my lunch.
4. Get an *** chewing (if it was from not watching your gauges or due to unserviced gear)

It's the right thing to do...

 

[fire_diver]

Here's a calculator I wrote that you can use to approximate air needs during an ascent:
http://cemu.org/scuba/ponycalc.php
Rob

I looked at your calc page, but I don't agree with it's results. Ive run the calcs many times, and many times more explaining it to others, and your results show WAY more CF of gas needed than what I come up with. Care to explain your equations?

FD

 

[MikeFerrara]

Then there are all the usual equipment configuration considerations...

Do you have an spg on that pony where you can monitor it throughout the dive? If not what makes you think there will be anything in it when you need it?

Can you reach the valve?

Is it quickly and reliably deployable? Is it neatly stowed in the first place?

The idea of being able to hand off a slung bottle sounds good but when was the last time you handed off a bottle under water? To an OOA diver? I wouldn't count on any of that working well unless you have practiced the move with that specific buddy.

In most cases of "pony use", they appear to just add clutter and complexity to an already cluttered up configuration without really solving any problem. Often divers, decide they want one about the time they start doing dives that are pushing it for the equipment and training they have. Fairly early in my dive career I came back from a trip wanting to buy a pony bottle. I drug my feet getting one because I didn't feel the need on most of my local dives. In further preperation for "those other dives" a little extra training and a little different approach to equipment configuration eliminated the perceived need for a pony and I never did get one. I've got lots of tanks and regs but none that I'd call a pony.

On the good side, if you get a small enough pony bottle you can always turn it into an argon bottle. If you get a big enough one, you can always use it for a decompression bottle or maybe a stage.

 

[jeckyll]

PS - If you dive with me and are OOA and use my pony. You will:

1. Refill it.
2. Buy my next air fill.
3. Buy my lunch.
4. Get an *** chewing (if it was from not watching your gauges or due to unserviced gear)

It's the right thing to do...

You don't check on your buddies air supply during the dive?



Wouldn't you have an indication that they are using more air than they should given where you are in the dive based on your plan?

It's the right thing to do