Is there a valid reason for a pony bottle

[tursiops]

What is the statistical significance of you personally never having witnessed something while diving?

THIS!
THIS!
A thousand times over!
THIS!

 

[markmud]

I guess I won't be able to explain to you how a catamaran hull works.

Well, the argument that seems to be constantly popping up is that the need for a pony is invalidated by proper care, maintenance, and planning. If proper care, maintenance, and planning is all that's needed to prevent a failure of your primary air supply, what is the point of people carrying an octopus?


Now personally, I don't think that is a valid argument and that most would agree that some degree of redundancy is a good plan. That's either a pony or a buddy. The biggest difference between the two is that a pony is available instantaneously and doesn't require trusting a stranger to have their act together.

Hi saxman242,

Your points are very profound, except I like a good buddy and a pony.

markm

 

[tarponchik]

A burst LP hose is also a reported scenario. Either of those can drain a full AL80 in a minute or so...

Burst LP hose? No kidding? If the 1st stage fails to control the pressure the air will simply leak through the 2nd stage or octopus. Unless the hose was badly mistreated or was too old, of course.

 

[tarponchik]

THIS!
THIS!
A thousand times over!
THIS!

A believer in stats should have noted the next sentence: "A burst LP hose is also a reported scenario." So what is the statistical significance of a reported case?

 

[markmud]

He wants every dive to be two hours or close to it. He was using his pony to extend dives. I prohibited his pony and said he must surface with at least 200psi in his tank. He gets in the water before we do and is often down for ten to fifteen minutes after we surface. That works for us as it gives us space on the deck to rinse off and get out of our drysuits before he comes up. He doesn't need to run his tanks dry just to get a few more photos. I'm trying to train him to be more careful. He dives with two computers, each telling him his remaining air as well as remaining bottom time based on his depth and pressure. There is no reason for him, or anyone to purposely run a tank dry underwater.

Hi Max,

Thanks for responding.

"He wants every dive to be two hours or close to it."

What profile is he diving.

As I recall, a dive to 60 fsw will get into staged deco in about an hour--is that about right?

Either he dives quite shallow, or he is doing staged decompression diving?

If he is diving that shallow, he probably does not need a pony.

If he is doing staged decompression he should have redundancy. That is the standard in the industry.

I am confused.

markm

 

[saxman242]

Hi saxman242,

Your points are very profound, except I like a good buddy and a pony.

markm

That is my preferred combination as well. I know there are dives that I will do where I will have a good buddy and a pony is less necessary and there are dives that I will do where I'll discover on the dive that my insta-buddy certainly isn't a good buddy and will be very glad I have the pony just in case. I'll carry the pony on the former dives as practice for the latter.

 

[markmud]

That is my preferred combination as well. I know there are dives that I will do where I will have a good buddy and a pony is less necessary and there are dives that I will do where I'll discover on the dive that my insta-buddy certainly isn't a good buddy and will be very glad I have the pony just in case. I'll carry the pony on the former dives as practice for the latter.

Saxman242,

We are on the same wavelength. Diving with a pony is just to easy, IMHO.

markm

 

[lowviz]

Your points are very profound, except I like a good buddy and a pony.

I like a good pony too, it is an equipment solution to a buddy problem.

Has anyone's position changed?

 

[MaxBottomtime]

Hi Max,

Thanks for responding.

"He wants every dive to be two hours or close to it."

What profile is he diving.

As I recall, a dive to 60 fsw will get into staged deco in about an hour--is that about right?

Either he dives quite shallow, or he is doing staged decompression diving?

If he is diving that shallow, he probably does not need a pony.

If he is doing staged decompression he should have redundancy. That is the standard in the industry.

I am confused.

markm

Most of our dives are in the 35-65' range. If we're diving on a reef with kelp we spend quite a bit of the dive looking for tiny animals up in the kelp, sometimes just a few feet below the surface. All of our dives are on 32-34% nitrox. Using a 130 and being a small guy, he can easily get two hours. Until I instituted the new rule, he would extend those dives with a pony.

 

[doctormike]

A believer in stats should have noted the next sentence: "A burst LP hose is also a reported scenario." So what is the statistical significance of a reported case?

Dunno. Don't have that data to give you a number.

But claiming that catastrophic gas loss isn't a risk because in one person's dive experience it hasn't happened is certainly not statistically sound. I have never seen a mola mola. Does that mean that they aren't real?

On the other hand, several of the handful of people commenting in this thread have personally witnessed or encountered this. Therefore, while I can't give you a precise incidence - I can comfortably state that it is an actual risk. Which is what we were discussing.