Carrying Three Regulators

[redacted]

Back on the boat, we took the valve off of the pony bottle and puured about a litre of water out of it..

What does the liter of water in the pony have to do with this incident?

The cure for gross mismanagement of gear is not necessarily to eliminate the mismanaged gear. A long hose primary with a bungeed octo and a pony reg mounted in a clearly different location should avoid such errors with all but the most talented of fools. Although both these divers seem to have been quite talented.

 

[captndale]

What does the liter of water in the pony have to do with this incident?

The water in the tank simply helped us to understand what had happened underwater. The fact that there was water in the tank showed that the tank was breathed dry and then the diver descended a considerable depth below that point before ascending again. That shows a loss of buoyancy control in the stress of the situation.

The cure for gross mismanagement of gear is not necessarily to eliminate the mismanaged gear.

I disagree. Gear that is easily mismanaged will be mismanaged. If you eliminate the potential for for the problem the problem is eliminated.

 

[captndale]

Double post - sorry.

 

[captndale]

A long hose primary with a bungeed octo and a pony reg mounted in a clearly different location should avoid such errors with all but the most talented of fools. Although both these divers seem to have been quite talented.

These two divers were divers I would not have expected such actions from. They were, from all outward evidence, very experienced recreational divers. It is quite surprising how talented a fool even the best divers can become on a cold, deep dive when things start to turn wrong.

As for the whole issue of pony bottles - Advanced recreational divers are encouraged to use them and I might even concede that they have a place, but I am generally not a fan of them. A manifolded set of doubles or a single tank with an "H" valve and an appropriate gas management plan is vastly superior to the use of a seperate small bottle. If your plan calls for more gas than you can carry on your back, stage bottles that you can breathe down before you switch to your back gas should be used.

 

[gcbryan]

I would agree that perhaps using the OP setup that 2 second stages is best but slinging and using 3 second stages is even better and gives a diver more options without clutter. A bottle slung with the hoses banded around the bottle is no clutter. One primary hose for the main tank and a bungeed second is no clutter.

It could be beneficial for both divers to be able to share the main tank if it's early in the dive and the main tank is full. There are other reasons for having a bungeed second as well. If you have ever fallen on a shore dive and ended up on your back you would know the benefit of a bungeed reg exactly where it's supposed to be.

 

[atedeschi]

You are over complicating it, if you dive a pony bottle dive a 2nd stage on the ppony and one on the main tank. if not diving a pony put to 2nds on your main. no reason for 3 at all, you can make all the excuses you want, but no need for it.

 

[gcbryan]

You are over complicating it, if you dive a pony bottle dive a 2nd stage on the ppony and one on the main tank. if not diving a pony put to 2nds on your main. no reason for 3 at all, you can make all the excuses you want, but no need for it.

Not over complicating just thinking.

 

[redacted]

You are over complicating it, if you dive a pony bottle dive a 2nd stage on the ppony and one on the main tank. if not diving a pony put to 2nds on your main. no reason for 3 at all, you can make all the excuses you want, but no need for it.

If the pony is large enough that you can manage your gas like doubles then two 2nds should be fine. But for smaller ponies, like 13 & 19cf, that small supply of gas should be used for emergencies only. So filling lift bags and balancing back gas with a buddy probably should or could not be done. And, unless you carry that larger pony on all dives, you may be doing quite a bit of gear modification before and between dives. You also have to consider things like keeping your pony topped off if you are going to be using it in place of your alternate on you back gas.

The water in the tank simply helped us to understand what had happened underwater. The fact that there was water in the tank showed that the tank was breathed dry and then the diver descended a considerable depth below that point before ascending again. That shows a loss of buoyancy control in the stress of the situation..

Yes, a liter of water in what is only a 4 to 5 liter bottle suggests he would have had to do quite a bit of descending after OOA. Like the last 30 ft of the decent to 130 would have been after OOA. I suspect that much water may have come from some other source.

 

[Twiddles]

Interesting discussion, I appreciate the scenarios and past experiences. To address a question, I carry a Pony because I want an alternate air source, not just a means to reconnect to my only source. If I have a major gear malfunction, cut hose, failed first-stage, free-flow, I want a source unaffected by the original problem.

Frankly I don't understand why a pony isn't required (assuming of course you not diving doubles, etc)? I know that failures are fairly uncommon so I see the reasoning that the risk is so low that the requirement isn't needed. I just figure if I get into major trouble I want my rescue to be on me, not on somebody who may or may not be around. I can't imagine a situation where both first stage, or both hoses, or both tanks, or both second stages would fail at the same time?

Why is an SPG not needed on your alternate air source? I have a fair idea of my sac rate (it changes very easily). I have also removed my mask in 30 feet of water and had my breath actually yanked from my lungs (scared the crap out of me). The cold (48deg) hit my face and my air was gone, freaky. I imagine under a real emergency a similar reaction might happen and I would think you would need to know how fast your burning up your "gas"?

Or is it just that your ascending anyway so what difference does it make? If your low and breathing gets hard, your just gonna kick to the surface anyway, its not like the SPG is going to add air to the tank. The thought of going OOA a second time on a dive without seeing it coming, sort freaks me out. I would probably prefer to see it coming the second time.

Slinging a pony bottle and the size. I chose a 19cu bottle because from the rec dive limit at more than double my sac rate I can safely surface with a safety stop. Why would I want to carry a 30 (for my needs)? Why would you want to sling a bottle, so you can hand-off YOUR alternate air source? Why would a rec diver who dives reefs mostly between 50 and 75 feet of depth want to carry a bottle in front of him instead of out of the way on your back with the other tank?

 

[captndale]

Yes, a liter of water in what is only a 4 to 5 liter bottle suggests he would have had to do quite a bit of descending after OOA. Like the last 30 ft of the decent to 130 would have been after OOA. I suspect that much water may have come from some other source.

No one actually measured the quantity of water but it was a significant. A thirty foot drop on this dive would be believable because that is the drop from the deck of the wreck to the ground. I have seen it happen in at least one other "incident" at the same dive location.