The great Spare Air / SpareAir topic

[SueMermaid]

My first (now-defunct) workplace scuba club bought one of these things and by default, I ended up with it. (I didn't, however, end up with the two cameras we owned).
I did manage to take it on a dive in Belize just to try it out. I got exactly two breaths out of it. And so it sits, collecting dust, in my desk drawer. Any suggestions as to what I can do with it? Doorstop? Meat tenderizer? Keyboard duster? Tank banger?

 

[sbell]

[post removed by regulator]

 

[Rick Murchison]

SueMermaid once bubbled...
Any suggestions as to what I can do with it? Doorstop? Meat tenderizer? Keyboard duster? Tank banger?

Cut the bottom out of it, hang a drilled ball-bearing in it with a decorative wind-catcher hanging down... it has a very pleasant tone as a wind chime.
Rick

 

[leadweight]

Fill it with vodka & have a swig every now and then on non-diving days.

 

[HarleyDiver]

Hey sbell,
They may have flamed you, but they were trying to save your life.

 

[Charlie99]

SueMermaid once bubbled...
I got exactly two breaths out of it. And so it sits, collecting dust, in my desk drawer. Any suggestions as to what I can do with it?

Uh, how about filling it before trying to use it!

Unless you were at 800' / 25 ATA, you should have gotten a lot more out of it. 3 cu ft = 85 liters -- even at 100'/4ATA that should be good for 10 or 15 breaths.

Charlie

 

[Northeastwrecks]

nt.

 

[Bob3]

We always use a SAC rate of 1.5 for those "oh ****" situations. It usually drops back down closer to 1 after the initial "oh **** ", but that takes several seconds.
By our calculations, a 30 cu ft bailout bottle will last 2-1/2 minutes at 220'

Here's the formula we use for calculation bailout duration: http://www.scubadiving.com/members/divetips.php?s=182

 

[scubadudee]

wow...thanks ...... but do you guys think if I were to bring a pony along for say a 7 to 10 cu ft tank?

I could harness it to my 18cu tank though.

 

[Spectre]

scubadudee once bubbled...
On unexpected circumstances, maybe like a strong current dragged you deeper thus past your NDL....would this help by a quick decomp for about 5 minutes ?

You seem to be comparing two different things. Are you saying that you went past your NDL _and_ ran out of air? There is no corallation between NDL and air supply. Just because you exceeded the NDL doesn't mean that your tank is empty?

You're probably better off planning your dive so that you begin your ascent with enough gas to get you and your buddy to the surface with a 5 minute stop. That way, if you happen to be out of air, your buddy can both of you, with the 5 minute stop, to the surface safely.

Even in a nice perfect world where you are breathing .5 cu ft per minute surface rate, that's 3.63 cu ft for 5 minutes @ 15. And this doesn't count an ascent. With the same breathing rate an ascent from 100 feet is going to take another 3 cubic feet. Now take in reality of the stress of the situation [a sac rate of 1 cuft per minute], and you're up to 12 cu ft needed.

You mention an 18 cuft tank. What's that? A pony? Why would you need more than the pony? Perhaps you should rather think about upgrading that to a 30 or 40 if you don't feel it's sufficient.

If you're concerned about this at all, you probably shouldn't push your NDLs anyway.

Search the site for 'pony'. There is plenty of arguments about the appropriate size as well as arguments against the concept of a bailout bottle all together.