How many non-tech divers carry a pony bottle?

[Jason Ooi]

Why don't we dive with a double for the solo diving? Just use only one bottle and the other is always your pony...

Good advice ...take IANTD deep diver course with twin tanks..

 

[Bigcape]

The terminology changes with the intent of the dive. As far as I am concernrd a pony is a stage bottle and a stage bottle is a pony bottle. For me it is for equipment falure and bad gas mgmt or you just a plain ol back-up.

I carry a 40cf for back up and a hot mix 19cf for my saftey stop wich is also long enough to be a stage especially at 15ft if ness. I can get 15mins on a 19cf

I dive with some Hoover vacuume cleaners (bad sac rates) so inorder to not have to bail with my buddy I clip my 40cf to a guy who has 500psig in his 80cf when I have 1500psig in my 95cf and away we go!! i call it my "save-a-dive bottle

 

[The Horn]

Bad gas managment seems to pop up here. Who cares it is normally not the cause of requireing gas. Even on the rule of thirds you hit 80 feet, main reg free flows or a hose busts. Rule of thirds...out the window.....change to alternate and ascend. For the most rec part there is just the tank on your back (now empty or shut off due to problem). Not twins.....your "twin" is slung or on some other bracket. Not everyone can afford to "twin" or has the frequency to dive in areas that twin tanks would be required. Who ever first frowned on the "pony" or "alternate air source" well sr*** them.

I find it great to practice/dive with a 30 cuft "in case" I wish to add deco or any other dive that would require more gas.

The most convienient way is to sling the thing but that is also another kettle of fish

 

[KMD]

?? That situation is what you have that 1/3 'in reserve'.

So you breathe 1/3 to go down and do what ever, turn the dive at 2/3's... OOA situation... you have 1/3 for yourself to get back up and 1/3 for your buddy.....

on a straight rule of 1/3's I dont see the issue. Cave divers have used it for years and do not have a direct exit to the surface.... in open water.... 2/3's is plenty of gas for both divers to get back up.

Of course you have to play by the rules and TURN at 1/3. If you go beyond 1/3 to go down ...... then you have an issue, but that is not a shortcoming of the gas plan, it is mismanagement of the diver.

In open water it may not be desirable nor safe to immediately surface. You may need to get back to the anchor line. Also running 3rds presupposes that after an emergency occurs the sac rates will stay the same.

If my RB is 1500psi and I have used 1000psi outbound and hit an emergency we now only have 250psi to make it back to the starting point.

 

[jeckyll]

Just to clarify, I'm a conservative diver and I watch my air, depth and dive time like a hawk. I'm not looking for a way of relaxing my current level of vigilance , I'm looking at increasing my margin of safety. I can't see any negatives in carrying an alternate air source.

Potential negative: You won't feel the need to stay as close to your buddy, or watch them as much.

Just a thought

 

[ArcticDiver]

I'm not a tech diver and don't plan on going down that track but I like the idea of having an alternative air source instead of an alternate air source. Nice to be more self sufficient.

I don't have a pony bottle yet but it's going to happen soon - it's going to be either a 20 or 30 cu ft bottle.
Who else out there either has one or is in the process of picking one up?

Anyone out there with a pony bottle who removed their standard alternate regulator? I guess if you did you'd never be able to dive without the pony.

cheers

David

The very idea of a "pony"(small second gas bottle) instead of a "horse"(full size second gas bottle) is faulty thinking that has somehow gained some false legitimacy. Think about it.

Why carry more than one tank of air? Because you may need that air; that is why!

So, when perfectly adequate equipment and techniques are available for two same size tanks why would someone choose to use two different sized tanks? Because they haven't thought through the problem, or have fallen victim to the "be just like my friends" disease.

Especially for the traveling diver; using two same sized breathing gas tanks set up as independent doubles is without a doubt the best, and easiest, way to go. Just because the tanks are doubles doesn't mean they need to be manifolded. In fact, in many ways keeping the gas bottles independent brings certain reliability and ease of use benefits that are superior to manifolded doubles.

So, think it through. If you need more gas than in one tank you'll end up with some configuration of doubles.

 

[ScubaJewel]

The average sport diver who dives within safe diving limits needs nothing more than a pony bottle of around the 13-19 cu-ft size. This size is more than sufficient for an immediate ascent to a safety stop and then to the surface.

 

[MikeFerrara]

The average sport diver who dives within safe diving limits needs nothing more than a pony bottle of around the 13-19 cu-ft size. This size is more than sufficient for an immediate ascent to a safety stop and then to the surface.

A "sport diver" using a single tank on dives that are appropriate for a single tank don't need the pony bottle either.

 

[ClayJar]

A "sport diver" using a single tank on dives that are appropriate for a single tank don't need the pony bottle either.

Don't you just love truisms?

 

[MikeFerrara]

In open water it may not be desirable nor safe to immediately surface. You may need to get back to the anchor line. Also running 3rds presupposes that after an emergency occurs the sac rates will stay the same.

The rule of thirds assumes that you will use the same amount of gas on the way back but...that's a factor of sac/RMV and swimming speed.

We apply the rule of thirds when we MUST get back to the starting point. If that is the case, that rule of thirds is applied to a gas supply that has redundancy...manifolded doubles, independant double or even a single with an H-valve. If there is something about the open water environment that causes you to think that you need to treat it like an overhead, then you should treat it like an overhead...and a pony doesn't cut it.

If we MUST make it back then the rule of thirds is the most liberal gas plan that we use. For example, we might turn on thirds in a spring (flowing out) that we are familiar with. Since we have the flow pushing us out we get out much faster, with much less work and using much less gas. In low flow or no flow conditions or where there's is anything else that may complicate the dive we turn before a third of our supply is used.

If my RB is 1500psi and I have used 1000psi outbound and hit an emergency we now only have 250psi to make it back to the starting point.

If your RB is 1500 psi and you use 1000 outbound you are obviously not planning on getting back under water. Rock Bottom is ascent gas. What's left is useable. How you manage the useable portion is what determines whether or not you are going to get back to the starting point. Even using the rule of thirds, "thirds" are calculated after ascent gas or RB is backed out.