DIR and Pony tanks?

[lamont]

with a standard pony bottle (butt mounted), you are generally going to have issues with several or all of:

- reaching the valves
- checking the pressure (is there an SPG?)
- monitoring leaks in the first/second stages
- clipping off / finding the second stage

a slung bottle like a deco/stage bottle will solve most of these, but if you're planning on actually going OOA on your backgas (very *not* DIR) and needing it in a hurry, it may be a little more difficult to deploy in a race with time (although possibly faster than searching for a pony reg clipped off like an octo...)

you should also really be testing and breathing it down a little bit. so carry a al40, and during the dive breathe it down to 2000-2500 psi and then switch back to backgas and continue the dive and you know have confidence that you've got 26+ cu ft of gas. at that point your gas plan is so convoluted for a recreational dive that you're much better off:

1. dive with a buddy (or buddies) who can be relied upon to carry your reserve gas for you
2. dive with manifolded doubles

 

[mer]

a slung bottle like a deco/stage bottle will solve most of these<snip>

Just remember that in the GUE educational system, you would not be using a stage/deco bottle until Tech 1 due to the additional skills of managing the hosing and OOG procedures with a stage/deco. Often simplier will present you with fewer potential complications than adding more gear.

 

[MHK]

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

Others have done a good job discussing the why's behind the lack of necessity of a Pony bottle. Bear in mind, that the system most of us advocate, is the system we believe to be the most efficient when taken holistically. We never say to anyone that it is the only system available, but the system that works best for those of us that adopted it.

That said, I wanted to amplify some comments, and correct Max Bottomtimes' comments. One of the core tennants of the DIR system is that we dive as a unified team. You indicate that you are a former Marine, and I've been fortunate enough to have several former Marines as students of mine, and out of all of the students I've taught, it was the Marines that seemed to appreciate the benefits associated with unified team diving, and standardization amongst the team, more then any other group of divers I've taught. Simply put, in order to eliminate confusion in an emergency, we standardize the team to reduce the number of variables or if we should be in a limited, or a no-viz situation, we don't have to deal with a "personal preference" inconsistent with other team members. Furthermore, in training and diving within the ethos of a unified team, we consider all resources to be team resources, and that includes available gas. Our gas management protocols are such that we reserve sufficient gas for 2 divers to surface in OOA's, thus rendering the need for a "pony" beyond the scope of our training and team protocols. There is no sense adding a failure point, entanglement hazard, or additional drag when the issue is resolved with the team protocols and gas management protocols.

Which leads me to correct Max:

Max wrote:

"In the case of a 40 clipped off on the left, it is not called a pony because it is not used as a pony. It serves a specific need, deco gas only."

Reading Max's comments, one could get the impression that we don't use additional bottles called "stage" bottles. Stage bottles are rigged in the same fashion as "deco" bottles but are used as a mechanism to "stage" your dive to the extent it's an extended penetration and you need additional gas. Caves and/or wreck dives are often done in this fashion.

Bust as to your original question about how and/or why I believe you have been given the DIR rationale, but I'm happy to follow up if you need additional clarification.

Regards

 

[MaxBottomtime]

Which leads me to correct Max:

Max wrote:

"In the case of a 40 clipped off on the left, it is not called a pony because it is not used as a pony. It serves a specific need, deco gas only."

Reading Max's comments, one could get the impression that we don't use additional bottles called "stage" bottles. Stage bottles are rigged in the same fashion as "deco" bottles but are used as a mechanism to "stage" your dive to the extent it's an extended penetration and you need additional gas. Caves and/or wreck dives are often done in this fashion.

I was obviously referring to the OP's question about using a pony. In no way was that inferring he was considering staged diving. Of course you would use stage bottles for entended penetration dives, but we were talking about why ponies are not DIR. Most of the divers we see using a pony and those considering it are only using it for recreational profiles.

 

[oversea]

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

del

 

[MXGratefulDiver]

Personally I don't understand the position against a pony. Up here in the northeast, a good portion of the boats require doubles or a pony. Up here, most dives end up as solo.

The point being that if you trained, and dived, the DIR style of diving ... none of your dives would end up as solo. Therefore you would not need a pony, as your redundant gas supply would be in your dive buddy's cylinder.

People tend to get so wrapped about the axle on gear that they forget the foundation of DIR-style diving revolves around excellent buddy skills. Those who dive this way simply don't dive solo ... and work hard to develop their buddy skills to the point where they don't "accidentally" end up that way.

... Bob (Grateful Diver)

 

[Soggy]

Personally I don't understand the position against a pony. Up here in the northeast, a good portion of the boats require doubles or a pony.

Right...DOUBLES would be the 'good' option as well as the DIR option.

Up here, most dives end up as solo.

Only if you let them. I've never had a dive end up solo. If yours do, you have poor team skills and or a lack of discipline.

I just started getting out on the boats, I am not ready for doubles and neither is my wallet (although I have the tanks).

Why are you not ready for doubles? Your wallet is a poor reason...if you don't have the equipment to do the dives safely, don't do them at all. It's pretty simple. Would you drive your car if the brakes didn't work just because you couldn't afford to get them fixed?

I carry mine as a sling bottle and its right there should I need it. I do not need to race to my buddy and grab his backup.
My.02

I'd bet you a large sum of money that I can get gas faster from my buddy than you can from your pony bottle....

The more I meet the experienced divers up here, the more tell me they don't want a buddy.

You just need to find a better group to dive with.

 

[matt_unique]

I think this question boils down to whether you subscribe to the DIR methodology. Right off the GUE website in reference to pony bottles: "In the event of an out-of-air emergency, you have your redundant back up swimming nearby--your buddy. A good buddy will be there. If he's not a good buddy--one of your most important "gear choices" was VERY BAD!!!"

I personally don't subscribe to this thinking at all. A buddy, as a human being, could never be as reliable as a totally seperate breathing system mounted on your rig that could be reached in total darkness with no communication or delay. Not even a single fin kick is required to access this breathing system.

Not a DIR flame - I will take a good idea from any source - I just don't buy it. I think the original question comes down to what you believe.

--Matt

 

[matt_unique]

...
I'd bet you a large sum of money that I can get gas faster from my buddy than you can from your pony bottle....

You can't possibly think this is true Soggy....The only way you could even match the time would be if you were never - not even for a single second at any point from splash to exit - less than an arms reach from a buddy's reg - with night vision goggles (if diving at night). I could go on with this but I think you get the point. This is precisely my argument against the DIR response to the pony bottle. You could not possibly dive with a buddy in a way that would enable the advantages of a pony bottle.

--Matt

 

[Soggy]

Yes, I do believe it. Considering that, to be smart about diving with a pony, you'd have to have the reg stowed in some way (to prevent entanglement) and turned off (to prevent gas loss), you would have to pull out a hose, find the valve and turn it on when I can just grab a reg out of my buddy's mouth who is always going to be close to arms reach away and paying attention to me. In addition, you are re-enforcing poor gas switching skills by not checking the MOD on the bottle, etc....And unless you change the contents of the bottle for each dive, you may or may not be breathing a safe gas (too rich, too lean, too narcotic). Your buddy always has a safe breathable gas.

The difference is, you look at team diving in a completely different way than I do because you either don't like it or have never dived in a team with good team skills (and have chosen to not develop those skills). That's ok.

You can't possibly think this is true Soggy....The only way you could even match the time would be if you were never - not even for a single second at any point from splash to exit - less than an arms reach from a buddy's reg - with night vision goggles (if diving at night). I could go on with this but I think you get the point. This is precisely my argument against the DIR response to the pony bottle. You could not possibly dive with a buddy in a way that would enable the advantages of a pony bottle.

--Matt