Two 2nd stages, but only a single first stage?!?

[GrumpyOldGuy]

I will not be diving solo. I will have a buddy. The pony is just in case the ship hits the dam.

I was pointing out if your diving solo and you run OOG switch to the small pony, you know you have enough as to ascend. Your pony is right there for you, you practiced with it, you know the valve drills and no panic should result. Just ascend and skip the safety stop if needed.

You OOG buddy will me married to you if your pony is tank mounted. He may not be as calm as you, maybe he chased you down for the air. He probably had not practiced with it. Maybe the valve will be off. He will have a limited air supply (13cf) and you have to ascend together. If he runs OOG a 2nd time before hitting the surface it can get real ugly. Something to consider before combining a small pony, back mount and ditching the extra 2nd.

 

[houe]

Well that is why I also am considering an air2/inflator reg as a possible addition to the setup without adding an extra hose. However for the depths I plan to dive (60ft tops) I think a 13CF tank would get a person to the surface reasonably well. On the other hand it does seem like one wouldn't want to lose the larger gas supply in an emergency (assuming the problem didn't affect an AAS) if it could be avoided.

 

[Tigerman]

Why ditch the extra 2nd in the first place? Its not like its a lot of weight or drag.
Having a redundant air supply doesnt mean you have to ditch the octo..

 

[GrumpyOldGuy]

Well that is why I also am considering an air2/inflator reg as a possible addition to the setup without adding an extra hose. However for the depths I plan to dive (60ft tops) I think a 13CF tank would get a person to the surface reasonably well. On the other hand it does seem like one wouldn't want to lose the larger gas supply in an emergency (assuming the problem didn't affect an AAS) if it could be avoided.

There are lots of ways to solves problems (or more correctly work around problems) by tossing in more gear and yes, an Air2 will work. I don't want to get into a you need a pony / you don't thread, way too many of those exist and in the end its your dive environment, your life. Just remember 2 key issues.
1) The more equipment and the more complex it is, the more likely something will go wrong.
2) The most unpredictable component is a) your buddy and his dive style, b) you and your attention to gas & dive plan

So, the Air is will save you a hose, but its more complex and not standard. Example: if you have something simple like a sticky inflation valve on a normal BCD, you disconnect and continue your dive. No big deal. The same issue on an Air2 should end you dive (no AAS). Its a choice, both work. I choose the standard 2nd since I have many dive kits.

 

[houe]

I know many people are against the AIR2 systems - I've read the threads. However, with a pony it seems like diving around with three 2nd stages is a bit much. An AIR2 in this situation seems like a workable solution since it doesn't really add much clutter. I'm trying to keep an open mind on how i want to set this rig up. I still have not purchased any of the items, but getting close...