Testing a Spare Air

[markmud]

My simple take on this is that some extra air is better than none. more extra air is better.
I started with a 6 cu ft pony, then progressed to a 13 cu ft. Pony and am now using a 19 cubft. Pony.

Was told by more experienced divers that a small amount of extra air could lead one to believe that they would be ok when in truth they might not be.

On a a slightly different topic, if you do have an air failure at depth and manage to control your panic I assume that one should ascend as much as possible without using the spare air in order to make what you have last a bit longer. Not sure about this but someone may have the correct answer.

Hey Bert,

Why the progression from 6cf to 19cf?

1. Did your dive profiles change?
2. Did you need more gas to extend your dive?
3. Was the 19cf used for other things and is handy?
4. Do you sling the 19cf on every dive?
5. Are you using the 19cf as part of your "rule of thirds" calculations?

There are no good or bad answers, as these are your decisions--it is all about your comfort level. Dive and let dive... dealing with different styles of diving.
Notwithstanding the above, I am interested.

I think the answer to your last question is yes. Continue to breathe off free flow or a failing primary system for as long as you can. Was that related to the question?

Cheers,
markm