No air left. Unable to do controlled ascent!

[DevonDiver]

Anyone can make a mistake. The low air and possible spg error meant that you were caught out. However, as a general rule of thumb.... as air starts to get lower.... then it is time to get tighter with your buddy.

Most people start their dive cautiously, and then relax (and get sloppy) as time underwater passes and, eventually, even allow themselves to get distracted from their 'core dive management'.

In reality, the opposite should happen. Having made a safe descent, your awareness and team (buddy) work should get stricter over the course of the dive - as air gets lower, NDLs get closer and our attention is most liable to wander....

Any time you get close to the 'red zone' on your spg (500psi/50bar)...or anytime you start to worry, in any way, about your gas supply (or any other problem)... you should make sure you are damn close to your buddy...and that you have their attention.

Also... there is a lesson to be learned about signalling your buddy if you have a potential problem.

500psi or less is low on air. There is a standard hand signal taught for this situation in every OW class. USE IT. If you had... then maybe your buddy would have been closer and waiting to assist once you ran out of air.

 

[bacaruda]

You made the correct decision to go for your buddys octo.
You asked what you could have done differently.
In a situation where a second air-source isn't an option (buddy missing or to far away) there is one thing that is essential: establish positive bouyancy!
With no air left there is only one way: drop your weightbelt.
Me and my daughter practice this quite frequently (in wery shallow water) so that in an emergency, there will be no hesitation in where the hands will go to release the integrated weights.
The small amount of air still in your tank will expand on the way up, giving you the possibility to inhale maybe once or twice.
Haven't been forced to try it out my self, but a friend of mine run dry at 60 ft (manometer malfunction), No air in the lungs he ditched the belt as a reflex and headed for the surface. He got one breath on the way and came out ok, but shocked. We both purchased pony bottles after that incident. I'm trying to convince my daughter to use ponybottle as well, but she claims that her type of diving doesn't call for a pony.
I don't care if a dive is "easy" or not. You never plan for "running out of air", so the pony goes with me all the time.

 

[Rick Murchison]

... It is recommended that new dry suit divers only use the suit for control...

Who's "it?"
It sure ain't me!
I say again, use the drysuit inflator only to maintain loft in the underwear; use the BC for buoyancy compensation.
Do it from the very first time you don the drysuit and you won't have to unlearn a bad habit later.
Rick

 

[Rick Murchison]

... My instructor taught us to use the drysuit for buoyancy control, not the BCD... My instructor told me 5 times after this happened that I should have went to the surface regardless...

Instructors are just folks too, not beyond improving their knowledge and skills. Refer your instructor to this thread.
Have him/her join the instructor-to-instructor forum on Scubaboard and we'll discuss this stuff - and maybe we'll all learn something.

Rick

 

[Rick Murchison]

... Fast accents in dry suits are VERY tough to control because its tough to get that much gas to move to the vent and get out of the suit. You basically end up spread eagle to create the most drag and slow down.

Maybe it's suit dependent... I've used a Dive-Rite 905 for the past 6 or 7 years, but had an Oceanic 7 mil for years before that which added expanding neoprene to the problem. On a training weekend I may do 16 or more CESA's and I've yet to have a problem venting enough air to control ascent rate.
Rick

 

[fppf]

Rick
The major training agency's all teach to only use the dry suit.
And I would expect an instructor to be able to do CESA with a dry suit. I can, but never had to. I would not expect a new dry suit user to be able to pull it off in a real situation.
I'm not saying using the BC is wrong. I use my wing every dive. I'm just saying how the training agency teach people.

As for dropping your weight belt, this is the absolute worst thing you can do IMHO, especially in a dry suit or thick wet suit. Going 20+ lbs positive will take any control of your accent rate away from you. If your diving correctly and are close to neutral when you run out of air you can just start to swim up. Once you ascend a few feet the air in your BC and suit will start to expand to the point of needing to vent it to keep your accent rate under control.

 

[Wookie]

As for dropping your weight belt, this is the absolute worst thing you can do IMHO, especially in a dry suit or thick wet suit. Going 20+ lbs positive will take any control of your accent rate away from you. If your diving correctly and are close to neutral when you run out of air you can just start to swim up. Once you ascend a few feet the air in your BC and suit will start to expand to the point of needing to vent it to keep your accent rate under control.

Wow! In 20 years of operating 2 liveaboards, the crew of these liveaboards have recovered 4 weightbelts. That were firmly attached to 4 dead bodies. I only saw one of them. I saw him die. I saw him surface, put up his safety sausage, signal the boat that he needed a ride, and by the time the Divemaster got to him, he was gone. As sunk back down. This is a man who should have lived, but he traded his life for a $25 weightbelt.

I've watched the rescue of countless divers. Nothing was wrong with those divers that experience wouldn't have fixed. For the first few years I was the captain of this boat, I watched as 90% of those rescued divers got back on the boat with their weightbelt on. Sometimes I'm a little slow. Now, I beat my divemasters into submission regarding rescues. Like we were all taught in rescue class, drop the friggin' weightbelt. Panic over. That fast in most cases.

I can fix an embolism. They aren't that scary. I can fix bent, I've had to do it a bunch. My lovely wife can fix dead, she's done it once (he had his weight belt on, too). I can't do it, I can't fix dead, so drop the damn weightbelt. It's not worth your life.

 

[fppf]

You are talking two different situations.
I'm more than happy to drop my weights on the surface. But at 100 feet I know if I swim up a few feet I get a free, controlled ride to the surface anyway. Its not a money thing, I have more lead here than I know what to do with. Its shooting to the surface 20+ lbs positive with no hope of slowing down and popping out of the water like a breaching whale. That's if the boat is not over me, which in that case I break my neck.

You can't fix an air embolism, most people that embolism are dead before they hit the surface. You can fix bent, but if your doing a CESA your last worry is bent.

 

[scubette]

I've read all the replies about what my instructor has said to me. His reasoning why is that PADI has done away with "buddy breathing" and he told me that since I swam back down to get air, I had put my buddy at risk and in harms way and I shouldn't have done that. I beg to differ as I needed air because I had no air to exhale while ascending and he had enough air for the both of us. I know when we made it to the surface, my buddy attempted to inflate my bcd by way of my octo but there was nothing left in the tank.

Last night I was thinking that since the drysuit inflator button was in the middle of my chest it could have been accidently pushed by my Zeagle Zena BCD which zips up the front. I did have to unzip the BCD about 2" to clear the drysuit inflator button....maybe that could have been the cause of my losing the air so quickly?!??

Thank you all for your suggestions and comments and I will definitely look into the rescue course as that will be very beneficial in all regards !

 

[Wookie]

You are talking two different situations.
I'm more than happy to drop my weights on the surface. But at 100 feet I know if I swim up a few feet I get a free, controlled ride to the surface anyway. Its not a money thing, I have more lead here than I know what to do with. Its shooting to the surface 20+ lbs positive with no hope of slowing down and popping out of the water like a breaching whale. That's if the boat is not over me, which in that case I break my neck.

You can't fix an air embolism, most people that embolism are dead before they hit the surface. You can fix bent, but if your doing a CESA your last worry is bent.

Respectfully, you're wrong. Exactly how many embolized divers have you seen and allowed to die? And I'm not talking two different situations. Drop your weights from your drysuit at the bottom sometime. You don't breach, you don't come up feet-first (unless you started that way), you don't bust the surface and pop half-way out. You don't break your neck. In a shell type drysuit (I wear a CLX-450) from 40 feet to the surface, I estimate ascent rate at about 100 FPM, between two and three times what is recommended. I didn't die.

You've read way too many accounts in the "scare the new diver" manual, and need to go out and get some life experience. The highest diving embolism mortality rate I could find as related to scuba was 23%. I may be beating the odds.

Obviously, you have some strong opinions about drysuit diving. It's all good, there is room in the ocean for both of our theories. Remember, your brain is the very best tool you'll ever use while diving. Don't discount what you know until you prove it one way or the other.

Frank