Backup Buoyancy?

[SailNaked]

well honestly the Steel 120s are on my wish list to purchase, I have the 80s. You do not have to use all the air in your tanks but it is nice to know it is there.

My goal is to dive every wreck I can find under about 150' find some buried treasure buy a bigger boat and then keep diving till I am old.

2 steel 120 are about 22# full, I think the worst case would be a total wing failure at the turn point at 130,(don’t make me look up the details). so they would weigh about 15# I might be able to swim that up, would really depend on how much of it was offset by my wetsuit we can assume at least 6#(likely more). so about 9# to swim up. we will assume the boat did not float off while I was under so at worst I could tie off the tanks with the sausage and dump em at my stop.

I have a single bladder wing and I suppose I can either buy another one or buy a double bladder, or I can save my money and get a dry suit.

 

[rjack321]

Skip the 120s. Not sure why they are on your wish list at all, they are like long skinny water heaters. I don't need my 119s until I start hitting 200ft, and I'm in 46-54F water. And even then I am way more deco gas/time limited than I am by ~250cf of bottom gas.

80s and a bottom stage will be ample gas for anything in the 100-150 range. If doing penetrations use the first half of the bottom stage to get in and the 2nd half to get out - with the backgas in reserve. Easy easy penetration math. This combo of tanks also gives you enough backgas to do a 150ft dive and then a shallower 100ft dive.

I would get al40s for deco gas. And with this combo of AL80s plus an AL80 stage you can use a normal wing and skip the convulted dual bladder one of which will leak at some point and you'll have 2x as much of a CF trying to disconnect the right one before blowing your deco stops.

 

[IDS_Bill]

Is a safety sausage an acceptable form of redundant buoyancy when diving doubles wet. would a lift bag be a better option? assume best case 2x Al80 or worst case 2x Steel120s w/Al80 stage(deco). or is a double bladder wing the only way to go? I understand the best option would be to dive dry or have a second bladder, looking for what is reasonably safe enough. (please do not call me an idiot, I already know that, and yes I will die).

I understand there could be lots of variables, lets assume a hard bottom at 130 in relatively warm clear water. (like Florida).

I think the better way to answer your question is with a real world scenario:

You just finished a LONG dive on your steel 120's and are quite a ways into deco. You start your ascent in a mild current that carries you over a deep wall (like Cozumel) when your wing suddenly goes south. You are now plummeting down towards god knows what and have to pull out a Snausage, unroll it, inflate it enough to arrest your descent momentum (very unlikely btw) and then manage the buoyancy of the Snausage during ascent to prevent a runaway ascent.

Double Bladder wing in steel 120's!!!!!