The great Spare Air / SpareAir topic

If Spare Air was offered to use free on a dive boat would you use it?

  • yes

    Votes: 16 64.0%
  • no

    Votes: 9 36.0%
  • I would rather no answer

    Votes: 0 0.0%

  • Total voters
    25
  • Poll closed .

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XtremeSea1 once bubbled...
Lets do the math. If you have a 2.0 cf spare air (not sure of the sizes but they are small) That's 2.0 cf at one atmosphere. Now lets take that bottle to 99 ft (4 ATM)....now you have 0.5 cf of available air. Thats barely half of a breath at that depth. A 13 cf pony and cheap regulator costs about $25-50 more and you get a real redundant rig and a whole lot more air. They do throw your balance off a little but you can compensate with proper weight placement.

mhhhhh.... I dont think so, they are ridiculous but not so much

0.5 liters*200 atm=100 Lt gas
assuming a sac of 15 lt/min at the surface, if u are a 30 mt
(4bar) u breathe 60 lt/min, so if you want to srface from thath depth will take bout 2 mins ascending at 15 mt/min so if your average sac will be 37.5, say 40.
40*2=80, means you have all the time to surface and make a short stop at 3m

off course if you are deeper you die :bonk:
 
Bob3 once bubbled...
I hear someone is making a manifold so you can hook 12 of them together & have a realistic amount of gas.:D


Hmmm. That sounds like a good idea. After all, I can hold 12 Spare Airs, 6 on each side, by using the bungies on my Bungied Wings Of Death to hold them in place.
 
Rush once bubbled...
Hmmm. That sounds like a good idea. After all, I can hold 12 Spare Airs, 6 on each side, by using the bungies on my Bungied Wings Of Death to hold them in place.

Hey! if you can rig them all to open at once you could probably get going REALLY FAST to get away from sharks and stuff... :bonk:
 
dc4bs once bubbled...


Hey! if you can rig them all to open at once you could probably get going REALLY FAST to get away from sharks and stuff... :bonk:

Great idea ! I was kind of thinking the same thing, so after my last post on this thread, I went to my drawing board and went to work on designing a Spare Air propelled DPV. I also thought that when I have been at depth for a long time and am too tired to swim back up to the surface, all I would have to do it turn these babies on to get to the surface really fast !
 
Rush once bubbled...

Hmmm. That sounds like a good idea. After all, I can hold 12 Spare Airs, 6 on each side, by using the bungies on my Bungied Wings Of Death to hold them in place.

Make sure you alternate sides as you use them or your trim will be thrown off.

Mike
 
Instead of carrying them why not stage them? Clip one off to the mooring line every two feet.
 
MikeS once bubbled...
Instead of carrying them why not stage them? Clip one off to the mooring line every two feet.

Not a bad idea, but if I have to use Spare Air, then my diving skills are probably lacking to the point that I wouldn't be able to navigate my way back to the mooring line.
 
-BlueHole- once bubbled...


mhhhhh.... I dont think so, they are ridiculous but not so much

0.5 liters*200 atm=100 Lt gas
assuming a sac of 15 lt/min at the surface, if u are a 30 mt
(4bar) u breathe 60 lt/min, so if you want to srface from thath depth will take bout 2 mins ascending at 15 mt/min so if your average sac will be 37.5, say 40.
40*2=80, means you have all the time to surface and make a short stop at 3m

off course if you are deeper you die :bonk:

A SAC of 15 liters/min (approximately 0.53 cf/min) is pretty low even if you’re nice and calm. But in the situation that requires using a spare air will likely be stressful. So I would say a SAC of 1.0 cf/min (approximately 28 liters/min) is more realistic.

To ascend from 99 feet to the surface at 30 ft/min takes 3.3 minutes at an average depth of 49.5 feet. A SAC of 1.0 requires 8.3 cf to get to the surface. Oops you’re dead!

So maybe we can ascend faster, say 60 ft/min that takes 1.7 minutes. A SAC of 1.0 requires 4.2 cf to get to the surface. Oops you’re still dead!
 
I would have to agree with MikeS's calculation. At 100' you would get a breath and a half. Let's just hope your not caught on something or inside a wreck or a cave. Ascending normally from 100' and doing a short safety stop with a Spare Air is absolutely ridiculous and can't be done no matter how good you breath.

Bottom Line: when diving over 100' you should have some sort of redundant scuba and a Spare Air is not acceptable. For those of you who are relying on one why don't you actually try using it to asscend from 100' and see how far you get. At least it will be a practice run and you will be able to switch back to your primary reg. instead of dying!!:boom:
 

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