DIR and Pony tanks?

[CJ-62]

What are your thoughts on "pony tanks" as a redundant air source within the DIR system? Please include your working definitions/equipment assumptions so that we can avoid any misunderstandings.
Thanks for sharing,
CJ

 

[onfloat]

What are your thoughts on "pony tanks" as a redundant air source within the DIR system? Please include your working definitions/equipment assumptions so that we can avoid any misunderstandings.
Thanks for sharing,
CJ

They are not used.

 

[Arduous]

I'm not a big fan of DIR, but in the DIR-III video, George shoots this idea down, bigtime

 

[mania]

Cj - answer to your question is really easy to find - just check www.gue.com
Mania

 

[CJ-62]

Cj - answer to your question is really easy to find - just check www.gue.com
Mania

Copied from the supplied link:
Pony Bottles
A pony bottle is designed as a separate air supply to be used in an emergency. These units add unnecessarily to the bulk of a diver's equipment. Most divers exploring deeper water or overhead areas opt for the more sound principal of a back-mounted tank or tanks that allow for two first stages to be used. The single tank would have a Y or H valve while the doubles should be configured with a manifold connecting the tanks. In both situations, bulky equipment is reduced while allowing the diver proper management over his air supply in the event of a regulator failure.

So if I hard mounted a 40cuft pony to a single, the bulk issue is avoided and I have a truely redundant system. It may pale to the doubles but exceeds the Y/H configuration. I had hoped to get more of the "Why this is done is..".

CJ

 

[mania]

OK. I don't use pony bottles. I use doubles or singles with Y valve. But I'm not DIR yet (Fundies in September)
Mania

 

[CJ-62]

I'm not a big fan of DIR, but in the DIR-III video, George shoots this idea down, bigtime

By George you mean that Irvine guy right? Don't have the DIR-III video, so I asked the question. Could someone give an Ex-marine a synopsis of his comments or a link that works for a non-GUE member.
Thanks,
CJ

 

[onfloat]

Copied from the supplied link:
Pony Bottles
A pony bottle is designed as a separate air supply to be used in an emergency. These units add unnecessarily to the bulk of a diver's equipment. Most divers exploring deeper water or overhead areas opt for the more sound principal of a back-mounted tank or tanks that allow for two first stages to be used. The single tank would have a Y or H valve while the doubles should be configured with a manifold connecting the tanks. In both situations, bulky equipment is reduced while allowing the diver proper management over his air supply in the event of a regulator failure.

So if I hard mounted a 40cuft pony to a single, the bulk issue is avoided and I have a truely redundant system. It may pale to the doubles but exceeds the Y/H configuration. I had hoped to get more of the "Why this is done is..".

CJ

It has to do with dive planning and gas management. A Y/H valve gives you a redundant regulator to the same air source. If you are truly OOA then your redundant supply is on your team member's back.

 

[Soggy]

It all comes down to: If you don't need it, don't bring it.

You don't need a pony bottle, because you have planned your dive such that your redundant gas supply is on your buddy's back. In fact, ideally, you have planned your dive so that there are 3 team members and each one has enough gas to get two of you to the surface with a controlled ascent without blowing off any deco.

If you *need* a redundant gas supply (deep, deco, or overhead environment), then you bring a set of doubles with an isolation manifold.

 

[CJ-62]

It all comes down to: If you don't need it, don't bring it.

You don't need a pony bottle, because you have planned your dive such that your redundant gas supply is on your buddy's back. In fact, ideally, you have planned your dive so that there are 3 team members and each one has enough gas to get two of you to the surface with a controlled ascent without blowing off any deco.

If you *need* a redundant gas supply (deep, deco, or overhead environment), then you bring a set of doubles with an isolation manifold.

I don't plan to need a knife but I bring one along anyway. Along with a SMB, backup light, whistle on all dives and other stuff on night dives.

The base question is why is the pony forbidden but a H/Y acceptable? If the requirements for the dive get large enough then the proper pony looks like your primary. So how about non-manifolded doubles (twin singles)? The manifold would be better but I don't got one yet.
Thanks for your time,
CJ