Tank time

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Moray

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Location
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# of dives
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I will be using a 108 cf tank in Truk Lagoon for the first time.given an average sac rate ,how much more time at 130 feet can I expect to have vs. an 80cf tank at similar depth?
 
sac rate is moot ... it does not change with tanks
(108/77) -1 is a rough number
let me do the math............ i get 40%
it maya be different cause you should not count the last 500psi so that would be 86/64 or 35%
so thats now 2 votes for 35%
 
Assuming similar starting pressures of 3000 psi, 500 psi is one-sixth of either cylinder's capacity, so the ratios will be the same. Therefore 40 %. i.e. 90/64 vs 86/64
 
You only have 10 min max bottom time on air @ 130, so you may, depending on sac rate, just be increasing your emergency gas supply on a square dive. Not a bad thing, but NDL will always be close. If you are doing deco, wear doubles, or add a pony.


Bob
--------------------------------
I may be old, but I'm not dead yet.
 
Actually a little more than the cylinder differences. If you assume you had adequate reserve in the lesser cylinder then all of the additional gas can be used.
 
I will be using a 108 cf tank in Truk Lagoon for the first time.given an average sac rate, how much more time at 130 feet can I expect to have vs. an 80cf tank at similar depth?


Posts like this make me nervous when some one is headed off to Truk. I hope you take the manual for your computer cause your going want to know about those screens you have never seen before.
 
Posts like this make me nervous when some one is headed off to Truk. I hope you take the manual for your computer cause your going want to know about those screens you have never seen before.


At the very least, listen to this. Every dive story I hear from Truk seems to have a "then we spent XX minutes hanging in deco..." attached to the end.
 
https://www.shearwater.com/products/perdix-ai/

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