Open or closed valve on pony bottle?

[GrumpyOldGuy]

Open for a couple of reasons. Immediate access may be needed, unlike a deco bottle which is planned. A more subtle issue is you can mistake the yoke screw with the valve, especially if you are wearing gloves and back mounter or in the dark. If the reg is not pressurized you can remove the reg rather than open the valve in an emergency, going from bad to worse.

 

[CptTightPants21]

I have played out the few scenarios I could think of. I mostly boat dive and i do worry about coming down hard on the gunnel. I regularly dive in 2 to 5 foot waves on the Great Lakes. I'm not opposed to going back to inverted, I haven't even considered the set up though. Do you then bungee the LP hose to the tank? I currently use a 5ft hose on my main to donate so my pony reg is bungeed around my neck. Not doing any overhead just yet.

From this thread and many others, slinging a pony IS the simplest and safest method of diving a pony. There are plenty of videos and instructions online that show how to properly mount and set one up.

One of the best stories I have for slinging comes from a friend of mine. My friend probably have close to 400 dives at the time, tech training, an OW instructor, but he didn't have solo card so he was taking the class. In the class, instructor had him turn off his valve to similar OOA and switch to his pony. He turns off his valve, switches to his pony, and its completely OFF. 400 dives, well over 200 with either a pony and something happened where he forgot to turn it on. What could have been a bigger issue was remedied by looking at the valve right in front of him and turning it on. Now he had air and the instructor was right there, but image if something similar had occurred in less than benign conditions in a situation. Degrees of panic and mistakes affect even the best divers the procedure and method for dealing with those situations and circumstances should be procedural and straight forward.

If you still insist on backmounting it then inverted where you can reach the valve is better than a position where the valve cannot be reached. The pony is very well protected by your body and the dimensions of the primary tank. From your description, it sounds like your pony is octopus/backup 2nd stage. I don't really care for the pony is my back up 2nd stage philosophy, but there is nothing fundamentally wrong with it. Having that philosophy AND not having the ability to manipulate the valve/air source is a huge issue.

 

[stuartv]

That's definitely on my list of progression. Going off topic, do you use the same set of doubles on every dive? Or if diving in recreational limits do you then use a smaller set of tanks for convenience? Keeping the reg set-up the same?

I have 2 sets of double 120s and a set of double 100s. I normally only ever use the 120s for anything, rec or tech. I only use the 100s when I need to because it was not feasible or convenient to get the 120s filled.

 

[gcarter]

Open for a couple of reasons. Immediate access may be needed, unlike a deco bottle which is planned. A more subtle issue is you can mistake the yoke screw with the valve, especially if you are wearing gloves and back mounter or in the dark. If the reg is not pressurized you can remove the reg rather than open the valve in an emergency, going from bad to worse.

DIN

 

[Peter69_56]

That's definitely on my list of progression. Going off topic, do you use the same set of doubles on every dive? Or if diving in recreational limits do you then use a smaller set of tanks for convenience? Keeping the reg set-up the same?

I generally use doubles for 90% of my diving now even if recreational. The main reason is redundancy and a better setup than BCD, although I do like the simplicity of a BCD and single (but usually then sling a deco tank as backup air).

I will use 2 x 12 litre normally but also have a set of 2 x 10 which I use down to about 40m for recreational diving. I have found that really 2 x 7 lire dont have sufficient air unless 300 BAR and then they weigh the same as 2 x 10 litre at 232 BAR and 232 BAR are easier to fill anywhere (although I fill my own) over 300 BAR.

 

[mainedvr]

I need new gloves

I was going to point this out.... at least you get good use out of your gear...

 

[EricTheDood]

A pony should never be factored into gas planning, unlike back or sidemount doubles, so a leak or a free flow should make you no worse off than if you didn't have a pony in the first place.

So with that in mind, a pony valve should be open IMO, to minimize the chances of forgetting to open the valve under stress or narcosis (as others have already mentioned). I think the likelihood of fumbling with a valve in an OOA situation is relatively high compared to the likelihood of double-OOA (main+pony) in open water.