Runaway BC

[D_B]

just disconnect it , nothing will happen, no air will flow and your BC will not deflate .. only thing is that sometimes it might be a little hard to line up and get it re coupled under water but that's not the important part ... just practice disconnecting it so you can do it confidently and quickly if the time comes.

and while your at it , try inflating your BC by mouth , then when you can do it on land, try it in the pool after you surface .... another thing that you should have done in OW class

 

[dmoore19]

I went back and looked through the book and couldn't find it. I asked my wife if she remembers it and she didn't remember the instructor mentioning it.

So the procedure is to disconnect the inflator line and dump air right after? I can practice that on land no problem. Any way to practice this in a pool or shallow water? I'd like to practice this before it ever happens.

My PADI OW manual has it on page 117. We also practiced it in the pool during class.

(rev 12/06) Version2.08

 

[MauiScubaSteve]

I went back and looked through the book and couldn't find it. I asked my wife if she remembers it and she didn't remember the instructor mentioning it.

Which book are you looking through?

My copy that is handy is the PADI Open Water Diver Manual, Rev 9/02.

On page 112 there is a very large yellow section titled Confined Water Dive Two; SKILL REQUIREMENTS.

9. Demonstrate the response to a leaking low pressure inflator by disconnecting the low pressure hose from the inflator mechanism.

If the student actually reads and comprehends the Open Water manual, the student knows what skills are required on each CW session; page 164 for #3, 208 for #4 and 241 for #5.

So the procedure is to disconnect the inflator line and dump air right after? I can practice that on land no problem. Any way to practice this in a pool or shallow water? I'd like to practice this before it ever happens.

I teach that your right hand pushes left with the palm against the deflate button as your right fingers both push the low pressure hose right and pull the spring connector back to the left. Or the right hands fingers could be the left force on the spring connector. ScubaPro deflate buttons are among of the worst positioned for this IMHO, as well as nearly every inflator/alternate. Oceanic makes one of the best LP hoses with regards to this disconnect procedure. If you roll onto your back as this is happening you are dumping nicely during the disconnect, and then continue dumping as necessary.

It is very hard to really simulate the true event that this practices for.

 

[captain]

Updating my response because I misread what you said. Sure *if you're dumping from the rear dump* you can swim it down. If you're not dumping it probably won't work. The main dump is fast enough that I use that and don't exert myself.

Plus you are not swimming down against 30# of lift, you are swimming down the difference between your negative buoyancy and BC lift. If you start the dive 15# negative with a full 30# lift BC then you only have to swim down 15#

 

[dmoore19]

If you are using an Airsource 3 (like I have) there is a valve that slides down and you shut the air off to the BC. I have both the standard lp inflater (with a hollis 321 for my alternate source) and an Airsource 3. I practice with my equipment and know how to shut the air off or disconnect it should the lp inflator stick. I also show my buddy if I am using my Airsource 3 as it is a little different than most set ups.

 

[DayBob]

I stand corrected. It is in the book. Wife and I still don't remember this being discussed in the pool session. I'm glad I saw this thread. Disconnecting the hose isn't something I would have thought of if it happened for the first time under water.

I learn more stuff on this board everyday. It's a great asset.

 

[SNorman]

Plus you are not swimming down against 30# of lift, you are swimming down the difference between your negative buoyancy and BC lift. If you start the dive 15# negative with a full 30# lift BC then you only have to swim down 15#

Well I know I've tried before with my setup and I couldn't swim down without dumping air unless I was only a little over inflated . Maybe you're just a better swimmer!

 

[beautybelow]

The best "runaway BC" I have witnessed happened when I am pretty sure the guy hit the inflate rather than the deflate thingy and panicked...probably hit the inflate again...panicked some more and actually ditched the BC in about 50', swam directly to his wife and grabbed her alternate...and directly swam her as fast as he could to the surface. I didn't see him ditch the BC and all I can remember thinking at the time was what the hell was a snorkeler doing dragging my diver to the surface? Luckily, nobody was hurt. The BC was picked up on the surface with a 60lb bladder fully inflated, probably some of the pressure bled off from the ascent.
True story.

 

[Zeldah]

If your instructor did not make a big deal out of the possibility that the BC inflator may one day stick in the on/inflate position, then your instructor SUCKED. No other way to put it and it is not your fault. A stuck inflator is probably the most common scuba failure other than a free flow.

If you ever get into an uncontrolled, buoyant ascent, you need to roll onto your back flair out like a sky diver and dump air from the inflator and simulateneously try to disconnect the inflator hose (if the cause of the problem is a freeflowing/inflating inflator).

I get so pissed when I hear that new divers have not been taught this stuff.

I knew I read this board for a good reason! I am doing my open water dives in a few weeks and when doing pool classes we covered a free flow problem and CESA but nothing about a stuck inflator .... reading this post means I will be asking the instructors to teach me this skill on my checkout dives. Thanks for sharing this

 

[still new]

I had a similiar event early in March, due to my own stupidity. I religously have my reg checked before my yearly month vacation in Mexico, but, this year I didn't check my BCD(DUMB) on my first dive I was a bit overweighted and added a little air to my BC and then took off for the surface, I flared, I dumped air but still kept going, only when I popped up on the surface did I remember to release my LP hose! On checking my inflator I noticed the little spring valve was corrided bad enough that it busted allowing the air to run. Good lesson learned a dive lost and an embarassing boat ride back to shore when the other 8 divers finished. NEVER AGAIN will I not check my BCD.