No air left. Unable to do controlled ascent!

[MXGratefulDiver]

In fairness to the instructor there has to be a cut-off point (depth) at which point a diver may choose a CESA as opposed to testing the rescue skills of the nearest diver. 47ft, although deep enough for all manner of trouble is within striking distance of most divers ability to effect a safe return to the surface unaided IMO. I am predicting this defense along with miss-communication from the instuctor. Instructor opionions?

This instructor disagrees. You follow your training. Your training was to dive with a buddy. The primary reason you dive with a buddy is so that you can be there to assist each other if one of you has a problem that requires assistance. Every agency trains their OW divers how to share air. All agencies also teach CESA ... but they do so at shallower depths than 47 ft. A new diver pushing those limits not only doesn't know if she can make it ... but the attempt is likely to induce a level of stress that can easily lead to panic ... which could lead to a much more serious situation.

So which is better ... to do something that you were trained to do under the circumstances, or to do something that pushes the limits of your training, and presents inherent hazards beyond what you have been trained to deal with?

I know, for certain, which I'm going to advise my students to do.

... Bob (Grateful Diver)

 

[Scott L]

This instructor disagrees. You follow your training. Your training was to dive with a buddy. The primary reason you dive with a buddy is so that you can be there to assist each other if one of you has a problem that requires assistance. Every agency trains their OW divers how to share air. All agencies also teach CESA ... but they do so at shallower depths than 47 ft. A new diver pushing those limits not only doesn't know if she can make it ... but the attempt is likely to induce a level of stress that can easily lead to panic ... which could lead to a much more serious situation.

So which is better ... to do something that you were trained to do under the circumstances, or to do something that pushes the limits of your training, and presents inherent hazards beyond what you have been trained to deal with?

I know, for certain, which I'm going to advise my students to do.

... Bob (Grateful Diver)

Bob,
That all makes perfect sence to me. The playing out of all senarios is what is so benefical from regular particiation on this and other boards. I know I am a much better and safer diver now having been so active on the boards the past year. If the buddy system were foolproof there would be no need for CESA training. I am just saying...

 

[paddler3d]

A lot of good info on here.

A question for the OP which I couldn't find in any of the follow up posts. Well, it didn't jump out and bite me.

Did you have any ditchable weight? You mention an Zena BC, which isn't a BP. If you're properly weighted, you should have no air in your BC around 500psi and be neutral for your safety stop.

This is to anyone with a hose less AI computer. I'm not sure if your computer is hose less or not. My wife's rig is an Aeries Atmos AI hose less computer. For my sanity sake, she doesn't dive frequently, I put an SPG on her rig and it is clipped to her BC. It is faced away from her so I can easily see it. Also, it verifies what the computer is telling her. It is +/- 50psi.

Another way to verify you computer vs. tank pressure is to ask, or watch the gauges, when you get your tanks filled. I do it all the time with mine. If I ended the dive with 1100psi, I see what the pressure is when they are getting filled. If it is close to 1100psi, my gauge is working just fine.

About pony bottles. A 3cuft is real small. Frankly I'd look at something a wee bit larger, 19-40cutft.

 

[Brewski]

as some may know, a diver cannot use their BCD for buoyancy control underwater while diving with a drysuit.

This is not true, while it is common for instructors to teach using your suit for bouyancy control to minimize mistakes new DS users can make trying to manage two air sources, it is prefered to only add enough air to the suit to loft your undergarment for warmth and use the BCD for control

Low and behold, I was at 47 feet depth with 550 psi left in my tank. I signaled to my instructor and buddy and we started to ascend slowly.

550 is much to low to begin your ascent, why didn't you start your ascent at 1000PSI?

This is what happened next. When I reached 43 feet, all of a sudden all of my air was gone. Within seconds!!! Couldn't believe it. My buddy was approx 7ft below me as I was ascending just above him. I had already exhaled just prior to my air running out and could not inhale any air. There was no air in my BCD. I was stuck, stuck with no air in my lungs to slowly exhale or "aahhh" on the controlled ascent. My airway was closed. Actually, there was no controlled emergency ascent. I kept ascending, was at 32 feet, looked up to the surface and knew I could not make it. I felt like I was going to choke or fight for a last breath from somewhere, but knew it would be water. Didn't know what to do. My gut took over and I made a last ditch effort and swam down about 8ft to my buddy and grabbed his alternate air. I know I wasn't suppose to swim back down, but I had to, to essentially save my own life.

The greatest lesson you can learn from this part is to stay with your buddy! I stress this point to my students constantly. you should not have been separated by 7 - 8 feet, if you were ascending together looking at each other, you could have simply signaled out of oar taken your buddy's octo and continued to ascend in control.

To run out of air is one scary moment, but to run out of air and have NO air in your lungs to exhale to make a controlled emergency ascent is TOTALLY different.

Indeed it is, gladly your safe and able to post your experience here. Not only did you learn some valuable lessons, but others who read this will as well.

Besides from purchasing a pony bottle or 3cft spare tank, are there other skills or what could I have done when I had absolutely no air left in my lungs to exhale to make an ascent quicker than my buddy was ascending?? Very, very unsettling.

You really don't need a pony bottle, you need to monitor your air closer, and learn to ascend sooner. Don't push the limits like that. Your instructor really should have stressed some gas management. The simplest method is to use a rule of thirds. use one third your gas to start your dive, use the second third to return to the ascent point, and the final third is for travel to the surface and possible emergency use. had you followed this simple technique you would not have experienced that very frightening ascent.

 

[Brewski]

Scubette
From the post you have made I would recommend you re-watch the open water DVD if you own it. Read your open water manual again. And forget some of the bad information you say your instructor taught you.
You should be able to maintain a safe distance with your buddy. You need to understand that the first course of action in an out of air situation is to signal OOA, then secure your buddies octopus, only when you have your buddy's octopus in hand are you to remove your regulator. Then when you have calmed down the two of you safely ascend to the surface.

Please review your open water materials and understand them completely. for your own safety.

 

[Lead_carrier]

Thank you so much for all of your replies. They mean alot to me!! Regarding the drysuit, it was a rental from the manufacturer at their demonstration day. The rest of the gear is mine which was purchased new four months ago. My instructor taught us to use the drysuit for buoyancy control, not the BCD. That's probably why my buoyancy was out of control and used up alot of air. But I do not recall inflating the drysuit once after I saw my air was at 550. I was just shocked and will take y'all's advice to have my SPG checked out as well. My instructor told me 5 times after this happened that I should have went to the surface regardless, never to dive back down. I guess that's why it's still unsettling to me.

Just my opinion, Change instructors. Sounds as if some of his judgements could be a bit questionable.

 

[BabyDuck]

The simplest method is to use a rule of thirds. use one third your gas to start your dive, use the second third to return to the ascent point, and the final third is for travel to the surface and possible emergency use. had you followed this simple technique you would not have experienced that very frightening ascent.

this may or may not be a viable rule (not gonna argue that point), but it is *not* the rule of thirds. the rule of thirds is one third to the farthest point, one third back out from the farthest point, and one third for emergencies. by rule of thirds, you are getting back on the boat with 1000psi if you started with 3000 and didn't have any emergencies.

 

[geokr]

Think the smartest thing you did was 'fess up and ask for advice on this - you sure got it! I learned a lot reading rather than living the experiences of others as I'm sure we all did. Thanks for your post.

 

[Thalassamania]

A buddy who is 7 feet away (too far away, but that's another tale) is a superior choice to an OOA ascet of 47 feet. You made the right decision, you've got the right instinctls.

As far as an ascent is concerned, if you had your dry suit valve set properly it should have been relatively easy to make a fairly controlled ascent, however, at 60 FPM that'd take 3/4 of a minute, longer than you might be comfortable with.

With respect to a 26lb positive ascent, with proper flare and shoulder valve settings it is not a big deal. In a full flare with dry suit and my shoulder valve set to just the comfortable side of shrink wrap I can drop a 30 odd lbs belt and still hold my ascent under 60 fpm; it's a matter of flaring back enough that you rise through the water much like a fluttering leaf falls through the air.

 

[MXGratefulDiver]

With respect to a 26lb positive ascent, with proper flare and shoulder valve settings it is not a big deal. In a full flare with dry suit and my shoulder valve set to just the comfortable side of shrink wrap I can drop a 30 odd lbs belt and still hold my ascent under 60 fpm; it's a matter of flaring back enough that you rise through the water much like a fluttering leaf falls through the air.

It's also a matter of having the background, skill and mindset to pull it off.

There are lots of things I can do now that I could not as a newly certified diver ... and would not recommend to any newly certified diver. Notwithstanding their physical ability to do it, self-confidence can play a huge part in the success or failure of any unplanned maneuver ... which is why I believe your first option should almost always be to follow your training. As your experience grows, so do your options for dealing with emergencies. Of course, as your experience grows, you should be learning how to avoid those situations in the first place.

... Bob (Grateful Diver)