Reading through all the replies has been very interesting and I appreciate all the feedback everyone has given on the issue. Yes, I realized from the beginning that just diving one tank sidemount would be the easier solution, and probably what the DM will require. And I'm ok with that, even though it may require some hose changes on my regulators and SPG. However, if given the chance to use both, I wanted to make sure my air remaining signals wouldn't cause confusion.
So, simplist approach appears to be for me to signal when I've approached my turn around and ascent times based on what I determine those pressures should be. I think I'll use this method when diving with the wife and other buddies. Of course this only works if my buddies feel confident that I'm managing my gas appropriatly to provide them adequate air in either tank in case of an emergency.
I would think the above method would also be simplest to use with DM lead dives as well, and if they agree, then problem solved. If not, I either just dive a single tank or work out some form of air signels. Still not clear on the best way to handle what that would be though. If I signal each tanks pressure then the DM has to try and calculate what my gas state is. One thought I had was to keep a gas management table on a wrist slate to refer to that might look something like this. Keeping in mind though that I only get two tanks for both dives and that they usually don't want to see less than 500 psi in each tank when the dives are over.
Dive 2 would then start with the following pressures.
And then use these as a starting point for adding another column that would show a "Single Tank equivalancy" based on air used column. That way I could give air signal as if diving a single tank. But that sounds confusing just trying to explain it here! :depressed: Oh well... this is all more a mental "what if" at this point. Once I get more sidemount dives in I'm sure I'll find a method I'd be comfortable using.
Thanks again for the feedback, feel free to keep it coming
Paul
So, simplist approach appears to be for me to signal when I've approached my turn around and ascent times based on what I determine those pressures should be. I think I'll use this method when diving with the wife and other buddies. Of course this only works if my buddies feel confident that I'm managing my gas appropriatly to provide them adequate air in either tank in case of an emergency.
I would think the above method would also be simplest to use with DM lead dives as well, and if they agree, then problem solved. If not, I either just dive a single tank or work out some form of air signels. Still not clear on the best way to handle what that would be though. If I signal each tanks pressure then the DM has to try and calculate what my gas state is. One thought I had was to keep a gas management table on a wrist slate to refer to that might look something like this. Keeping in mind though that I only get two tanks for both dives and that they usually don't want to see less than 500 psi in each tank when the dives are over.
Tank 1 | Tank2 | Air Used | |
Start PSI | 3000 | 3000 | |
Turn Around PSI | 2500 | 2500 | 1000 |
Ascent PSI | 2000 | 2000 | 2000 |
Remaining PSI at surface | 1800 | 1800 | 2400 |
Dive 2 would then start with the following pressures.
Tank1 | Tank2 | Air Used | |
Start PSI | 1800 | 1800 | |
Turn around PSI | 1300 | 1300 | 1000 |
Ascent PSI | 800 | 800 | 2000 |
Remaining PSI at surface | 500 | 500 | 2600 |
And then use these as a starting point for adding another column that would show a "Single Tank equivalancy" based on air used column. That way I could give air signal as if diving a single tank. But that sounds confusing just trying to explain it here! :depressed: Oh well... this is all more a mental "what if" at this point. Once I get more sidemount dives in I'm sure I'll find a method I'd be comfortable using.
Thanks again for the feedback, feel free to keep it coming
Paul