Have you ever sucked the bottom out of your air tank?

[Fish_Whisperer]

Ive run out of air once - uncontrollable freeflow empties my main cylinder so i came up on my pony.

So, in your experience and opinion, a pony bottle is a good idea to carry along, yes?

 

[navillus]

I came close to running out of air once. I headed up the anchor line from 80 feet with enough air in my tank (700 psi according to plan agreed upon on the dive boat). On my ascent I experienced a painfully severe reverse block in my left ear. I could not clear it for the life of me! I used my contingency air in order to descend and then ascend very slowly to prevent ear damage. I made it to the saftey stop point with only 300 psi in my tank. Because it was on the third dive of the day, I still wanted to make a longer safety stop, so I bled my tank down at 15 feet until 75 psi. My buddy (wife) was with me at the stop and still had 500 psi in her tank when we finally surfaced. I am guessing it is for situations like these that we have the 500 psi in our tanks. I don't ever want to come close to that again.

 

[DandyDon]

I'm not touching the pony bottole question. I've screwed up with mine a time or two, but will not dive below 50 ft without it as a rule...

My buddy (wife) was with me at the stop and still had 500 psi in her tank when we finally surfaced. I am guessing it is for situations like these that we have the 500 psi in our tanks. I don't ever want to come close to that again.

Yep, the 500 pis reserve is to use if needed - but you should have switched to your wife-buddy's octo when you saw you were going below 500# well before she would, then back to yours when your pressures were about the same for the final ascent.

 

[navillus]

Yep, the 500 pis reserve is to use if needed - but you should have switched to your wife-buddy's octo when you saw you were going below 500# well before she would, then back to yours when your pressures were about the same for the final ascent.

At the time I didn't know whether or not to do that (share air when still had a little bit of air left). I did not feel paniced and was keeping an eye on everything during the entire ascent. I completed my planned saftey stop with the extra time wanted (maybe I shaved a few seconds). My wife was with me the entire time and I showed her my problem and my pressure gauge, so she stayed close ready to share if I asked.

In hind sight, it probably would have been better to buddy breath during the saftey stop. It would have been good practice during this minor emergency how to share air when needed. Also, it would have kept our tanks somewhat equal. You are right: what would have happened if she had a sudden freeflow or equipment failure? Looking at it in hind sight, I agree: I should have buddy breathed with my wife for both her and my safety and also for a good practice of emergency skills. We live and learn. If you make a mistake and live, make sure you don't live to make the same mistake twice.

 

[Web Monkey]

Nope. Never even close. And I don't plan on ever being close either.

I watch my air supply like my life depends on it, because it does.

Besides, the last 800 - 1000 PSI belongs to my buddy, so it's not really mine to use anyway.

Terry

While diving on one of my first dives after I was certified I ran out of air at 60 feet deep.

My father,uncle and I were diving on a reef that was 60 feet deep looking for lobsters!
Jason

 

[pasley]

Nope, only been as low as 280 once on a very long dive (time and distance) we were chilling at 15 feet when we hit 500 PSI and were just burning up the excess air swimming back from the pinnacles located 548 yards off shore.

Bug hunting it is easy to get distracted and lose track of the air. That is why I do not encourage new divers to go hunting, or doing photography until they are comfortable in the water. Bug hunting also increases the air consumption rate for most divers (the work of wrestling the bug and the excitement of the hunt) so you have to pay extra close attention.

 

[dkktsunami]

Only intentionally in pool and shallow lake. For real - never been close.

 

[DandyDon]

At the time I didn't know whether or not to do that (share air when still had a little bit of air left). I did not feel paniced and was keeping an eye on everything during the entire ascent. I completed my planned saftey stop with the extra time wanted (maybe I shaved a few seconds). My wife was with me the entire time and I showed her my problem and my pressure gauge, so she stayed close ready to share if I asked.

In hind sight, it probably would have been better to buddy breath during the saftey stop. It would have been good practice during this minor emergency how to share air when needed. Also, it would have kept our tanks somewhat equal. You are right: what would have happened if she had a sudden freeflow or equipment failure? Looking at it in hind sight, I agree: I should have buddy breathed with my wife for both her and my safety and also for a good practice of emergency skills. We live and learn. If you make a mistake and live, make sure you don't live to make the same mistake twice.

To prevent possible confusion - Sharing off of her octo in a careful & safe reg change, then back to yours for ascent was my suggestion. Buddy breathing is sharing the same reg, which we all did in OW class, but hope to never have to do. Not nearly as controlled.

One big problem with running a tank empty even as a practice thing is that you can easily get water back in the reg hose, maybe the first stage and tank. Not at all good.

 

[scubanick]

i did once sorta
we did our deep dive class and on the first dive we went to depth returned to 15 for safety stop and as i got to the surface i was playing around just swimming on the surface but breathing on my reg instead of snorkle and did not pay attention to the guage anymore since i was technically finish with the dive as i was walking out of the water i kepy my reg in my mouth and was breathing off it and it just got super hard to get air out it was like less than 100 but never really ran out "during a dive"

 

[Splitlip]

Not I. I did however see it happen in the 70's when guys were still diving J valves and no spg (called them Sea-View gauges). The guy reached back to open the reserve and found the lever was already in the down position. It was in 50-60 feet as I recall. The guys just surfaced and was able to nurse air from his tank as he went up. As I understanded the older regs would breath progressively stiffer as the pressure in the tank approached ambient pressure. (Mike Nelson did not have an SPG).