Do you actually see people diving with pony bottles?

[The Chairman]

Now we just have to find a pony solution that is acceptable to all three.

Not really. I have a rather unique approach to diving and I don't expect others to adopt it. Unless they like it. I don't point fingers on the boat, I'm not into expose' and all that. However, if you want to dive like I do, then I'll be glad to show you how. Other than that, it's dive and let dive. There are plenty of different approaches to diving. We don't have to wear a specific uniform to get wet. Dive and let dive. It's simple.

 

[CuzzA]

The point I've been trying to make is that there is no formal guidance on this. There are reputable suppliers that will sell you gear for back mounting a pony cylinder. There are accomplished divers (like @CuzzA and @Wookie) who dive this way. Usually the reasoning has to do with keeping the sides and chest clear so that other equipment can be placed there. I don't second-guess their reasons. There are ways to back-mount a pony cylinder safely. Perhaps the most common setup is to necklace the pony reg and use an Air2 or similar as the secondary regular for the main cylinder. There are also some people who configure the pony valve-down so that hose routing is different enough to be obvious.

The evidence is out there and we know from experience which configurations are safe and which are not.

@2airishuman, Thanks for the accomplished diver mention, but I'm not sure I fit that definition. Being in the company of some other divers on this board it's hard to claim I've accomplished anything, yet. I do dive as often as I can and am continuing my training.

For my typical diving it would be unsafe and cumbersome to sling a bottle, though I believe it is the best way to do it. For me, trying to manage a stringer, landed fish, a gun, a pony tank, three regs and whatever fish I'm wrestling with is a recipe for disaster, IMO. Back mounting and using an AIR2 eliminates a standard reg so to speak and frees the front of your body to load a gun and minimize line entanglement.

I agree back mounting can be safe if a diver has some forethought for his configuration. Here's what I can offer.

The pony reg should be different from your primary. If you're using identical regs you should at a minimum change the mouth piece to both feel different and visually look different. An after market mouth piece will solve that problem. A colored hose would also identify the reg. I don't think reg face plates are effective because you never see it as they face out from you.

If you back mount a pony I think you should necklace that reg and consider an AIR2. The argument of them being bad breathers is history. The SP Gen 5 breathes better than many primary regs out there. Obviously you have to practice your ascents. If you butt dump your wing it's a non issue.

There's definitely risk with backmounting so you have to try to eliminate those risks.

Here's a recent incident.
DUMB ASS NEWBIE PONY MISTAKE, Don't be that guy! - Spearboard.com - The World's Largest Spearfishing Diving Boating Social Media Forum

Here's my pony reg.

 

[Coztick]

Thanks for the replies,
The reason for the question is that on the odd occasion I have hit the 1000 psi accent pressure set by the op I use with less than 10 minutes left in a 60 min dive.
I was thinking that since I actually have the equivalent of 1450 psi on board, including the pony, that continuing for another 400 psi. could be considered responsible.

Drift diving I use 750 as my minimun for ascent. This gets me back on the boat with around 500.

Seems I would have more gas available at 600 psi of back gas plus 450 in the bailout.
I thought I'd run it by the board for review.

 

[lowviz]

...//... on the odd occasion I have hit the 1000 psi accent pressure set by the op I use with less than 10 minutes left in a 60 min dive.
I was thinking that since I actually have the equivalent of 1450 psi on board, including the pony, that continuing for another 400 psi. could be considered responsible. ...

First, it is best if you do your comparisons in cuft, not psi. 500 psi in a 130 cuft tank is nowhere near 500 psi in a 13 cuft pony.

Given that, I find it best to have two minds as to one's pony. One, you surface on your backgas at 500 and forget you ever heard about a pony. But (at the same time) know that your pony makes your 500 backgas golden.

Gas disappears at an alarming rate when things go sideways.

 

[JohnnyC]

There was a fun little discussion on a FB group where the OP posted that he regularly used his pony to extend his dive. Being that the captain on this Keys trip said everybody back in the boat with 500 psi, he would dive his AL80 down, go to his pony, and end the dive on his pony, trying to justify it by saying that 400 psi in his pony and 200 psi in his backgas was over 500 psi. He was angry because the DM called him out for being unsafe, and proceeded to trash on the DM.

Despite the fact that he was shown by several posters that the volume of gas was nowhere near what was stipulated by the captain on his boat, he continued to deny the fact that he was doing anything dangerous. He then took it to another FB group where he changed his story to try and get people on his side. Again, predictably, it devolved into him parroting that nobody knew what they were talking about and that he was right and the captain could go pound sand.

Point is, the scuba industry has long "standardized" a set of rules for gas management when boat diving, and people who think they know what they're talking about continue with unsafe dive practices out of a position of ignorance. Unfortunately, volumetric gas planning is severely lacking in the recreational dive world outside of some specific agencies. This should change. Recreational divers need to understand what the "500 psi rule" really means, and sadly, for the most part, they don't.

 

[lermontov]

Most OOAs are not due to malfunctioning equipment ... they're due to a malfunctioning attention span, particularly by people who are used to just jumping in the water and assuming that they will know when it's time to begin their ascent or turnaround toward shore. You can reduce that with a bit of arithmetic prior to the dive by making sure that you're carrying adequate gas for the dive plan ... but that also means you need to stick to the dive plan.

People are routinely taught this stuff in their OW class ... most either neglect to use it or don't really understand what they're being taught and why it matters ...

... Bob (Grateful Diver)

well easy solution just get a bigger pony - no dammit get two - better still get 2 Al80 -no I got it! a CCR -well actually a CCR and 2 Ponies - no wait - 2 CCR's ok ok just get surface supplied air -with bail out aaah

 

[lermontov]

Actually, I always orally inflate my buoyancy equipment. That air has already passed through my lungs, in other words "been used". Waste not, want not.

I always plan to have enough to not have to worry

 

[lermontov]

Still enjoying this thread...

I see three camps: Difference Between Optimists, Pessimists, and Realists - Glowball Web Network

Now we just have to find a pony solution that is acceptable to all three.

thats optimistic!

 

[Kharon]

First, it is best if you do your comparisons in cuft, not psi. 500 psi in a 130 cuft tank is nowhere near 500 psi in a 13 cuft pony.

Spot on. 3000 psi in a 13cf is nearly exactly 500 psi in an al-80.

I always plan to have enough to not have to worry

Yeah, I always have enough but more is better.

 

[MXGratefulDiver]

well easy solution just get a bigger pony - no dammit get two - better still get 2 Al80 -no I got it! a CCR -well actually a CCR and 2 Ponies - no wait - 2 CCR's ok ok just get surface supplied air -with bail out aaah

No ... the easier solution is to pay attention to your dive plan, if you need more gas use a bigger tank, or if you don't have a bigger tank modify your dive plan to accommodate the one you have.

Again, all of this stuff is taught in OW class. It only takes following your training.

... and writing stupid-ass remarks doesn't contribute anything at all to the conversation, but thanks for your contribution anyway ...

... Bob (Grateful Diver)