BC Failure

[LeadTurn_SD]

Notes to self:

1. Remember to tighten all twisty things on wing now and then.
2. Remember to not overweight myself.
3. Avoid combo pull-dump inflators... they are BAAAAD.
4. Do use normal elbow style inflators... they are GOOOOD.

-or-

5. Go back to diving without a BC like I used to in the 70's and 80's.

-and-

6. Disregard notes 1 - 4 to self

Seriously, thanks for posting your incident dumpsterDiver!

Best wishes.

 

[dumpsterDiver]

Notes to self:

1. Remember to tighten all twisty things on wing now and then.
2. Remember to not overweight myself.
3. Avoid combo pull-dump inflators... they are BAAAAD.
4. Do use normal elbow style inflators... they are GOOOOD.

-or-

5. Go back to diving without a BC like I used to in the 70's and 80's.

-and-

6. Disregard notes 1 - 4 to self

Seriously, thanks for posting your incident dumpsterDiver!

Best wishes.

If you are taking notes.. I typically will use safety wire to join the corragated hose to the various other parts, at the very least I use multiple zip ties. Some BC's will experience a similar failure, due to loss of a single zip tie.

 

[John C. Ratliff]

Gotta say I agree with Vladimir here...

Unless there was some reason that you HAD to complete the mission (Navy Seal? Rescue?) I would definitely not have continued a dive with an immediately identified and potentially life-threatening equipment failure, even with a buddy (let alone solo).

You are obviously far more experienced and trained than I am, and I'm not doubting your ability to accurately assess the immediate risk and options. But I worry that a less experienced diver will read this and take home the lesson that you finish the dive before dealing with the problem.

Even if you make it to the surface, if you have no dry suit and no BC, you have no buoyancy assistance. No anchor line? What if you got blown away from the dive boat? OK, you can always ditch your rig, but now you are treading water in the open ocean in a wet suit... hope you hung onto your signaling devices!

I'm just trying to think it through...

Dr. Mike,

I see you are a medical moderator, so I thought maybe I'd chime in here. I really don't think this was an emergency situation. BCs were developed over the years (and I had a bit to do with that too) to "compensate" for loss of "buoyancy," hence the name. They are not intended as life saving equipment. Indeed, one of my problems with most current BCs is that they will not float an unconscious diver face-up, which is why I developed the Para-Sea BC concept (which never sold). In this case, dumpsterDiver was maybe 16 pounds overweight at 80 feet. But it was still dumpable (release the weight belt), he had air, had his thermal protection (wet suit intact), so there really was no emergency in spite of the equipment failure. With the type of tank he was wearing, he probably had some significant weight from that tank and even dropping the weight belt would not have caused a buoyant ascent. He probably would have been close to neutral with the weight belt dropped. I did some experiments in the 1970s in fresh water, and went down with my 16 pound weight belt, took it off and hung it on the anchor line at about 30 feet, and swam around neutrally buoyant with a single 72 steel tank (which is neutally buoyant too). It was a great experience. In salt water I would have been maybe 4 pounds buoyant, but that's with a neutrally buoyant tank.

I would have probably done exactly what he did in this situation, decided to complete the dive and then come up with a swimming ascent. The initial kicking would have sturred the muck on the wreck a bit, but swimming up is not that difficult if he started neutrally buoyant at the surface (which he did). As he ascended, the swim became much easier as his suit regained much of its buoyancy at about 20-30 feet.

Where people get into trouble is in being quite negatively buoyant at the surface, and dependent upon the BC for surface floatation--this is very poor dive practice which has led to fatalities (as has been described here).

'Just thought I'd share this perspective.

SeaRat

 

[Insta-Gator]

Glad you made it out of that all right. Sounds like you had everything under control anyway. Experience helps suppress anxiety. But if any of us rec divers out here were to find ourselves in a similar situation and could not or was afraid to dump weight, how much negative buoyancy should an average skilled, average conditioned diver be able to swim up in a controlled manner? 5? 10? 15?

 

[Bogie]

Thanks for the post and excellent dive management solution.

One good thing about dry suits, you have a redundant buoyancy device.

 

[j yaeger]

instagator-
...i always judge it on the price of lead.....

have fun!
yaeg

 

[knowone]

Or the amount of air.

Or the price of the catch.

 

[LeadTurn_SD]

If you are taking notes.. I typically will use safety wire to join the corragated hose to the various other parts, at the very least I use multiple zip ties. Some BC's will experience a similar failure, due to loss of a single zip tie.

Thanks for posting that.

I've been "double zip-tieing" most things that are held on by single zip ties for awhile now, after seeing zip ties fail.

Best wishes.

 

[muddiver]

I guess I should add my two cents: I had a small BC failure on a working dive last month. Diving to swap-out fish trasponders.

I was geared up for cold water with a dry suit, my standard wing (DiveRite), standard rig and using the university's aluminum 80s.

After a dificult time trying to descend because I was a couple pounds short on lead (I normally dive a steel 100), I made it down to the bottom in 5 to 10 foot visability and a 1 to 1.5 knot current. On the bottom (85') I found my dry suit hose was not plugged in and it was getting just a bit uncomfortable. Having to 1) find and 2) connect that little hose with blue smurff gloves on took too long and by buddy thumbed to dive.

The BC problem became apparent on ascent. The inflator was bubbling more than my exhalations from my regulator and it was a bit perplexing. So at about 50' or so I disconnected the inflator hose. Bubbles stopped. Ok, keep ascending and dump as we go.

On the surface I re-connected the BC inflator hose and got more bubbles and hissing. So I discinnected it again after filling my wing enough to float safely.

Once on board the boat I found on close inspection that the male connector for the BC inflator hose was not screwed tightly into the plastic inflator body. So before the next dive I simply pulled out my tool kit and gave it a 1/4 turn past hand tight with a wrench.

Same point as the OP, check threaded connections every so often for loose and unscrewed components.

 

[doctormike]

Dr. Mike,

I see you are a medical moderator, so I thought maybe I'd chime in here. I really don't think this was an emergency situation. BCs were developed over the years (and I had a bit to do with that too) to "compensate" for loss of "buoyancy," hence the name. They are not intended as life saving equipment. Indeed, one of my problems with most current BCs is that they will not float an unconscious diver face-up, which is why I developed the Para-Sea BC concept (which never sold). In this case, dumpsterDiver was maybe 16 pounds overweight at 80 feet. But it was still dumpable (release the weight belt), he had air, had his thermal protection (wet suit intact), so there really was no emergency in spite of the equipment failure. With the type of tank he was wearing, he probably had some significant weight from that tank and even dropping the weight belt would not have caused a buoyant ascent. He probably would have been close to neutral with the weight belt dropped. I did some experiments in the 1970s in fresh water, and went down with my 16 pound weight belt, took it off and hung it on the anchor line at about 30 feet, and swam around neutrally buoyant with a single 72 steel tank (which is neutally buoyant too). It was a great experience. In salt water I would have been maybe 4 pounds buoyant, but that's with a neutrally buoyant tank.

I would have probably done exactly what he did in this situation, decided to complete the dive and then come up with a swimming ascent. The initial kicking would have sturred the muck on the wreck a bit, but swimming up is not that difficult if he started neutrally buoyant at the surface (which he did). As he ascended, the swim became much easier as his suit regained much of its buoyancy at about 20-30 feet.

Where people get into trouble is in being quite negatively buoyant at the surface, and dependent upon the BC for surface floatation--this is very poor dive practice which has led to fatalities (as has been described here).

'Just thought I'd share this perspective.

SeaRat

Hi, John...!

Those are good points, and while I am a medical moderator, my diving experience is nowhere near that of the OP or yourself, so I hesitate to argue diving specifics. It is true that a well balanced rig should be swimmable up from depths (is that grammatically correct?), and that people clearly were diving long before the modern BC was available. Please understand that I am not doubting either your or the OP's skills or ability to deal with the situation safely. I also totally agree with you about the difference between being overweighted at depth and on the surface.

However, I do stand by my comments in the context of this forum, where less experienced divers may take away a potentially dangerous message from this approach.

The OP stated that he added air to his BC at depth, and found it to not hold air. Thus, we must assume that he felt the need to add air. Also, he said that he made an "uncontrolled descent", enough to stress his Eustachian tubes, and that he was "pretty darn heavy".

Sure, in optimal circumstances, a diver should be able to swim his rig to the surface even if there is failure of his only buoyancy device. And the OP could probably handle a wide variety of mishaps due to experience and training… But the point is that this diver was overweighted at least at the start of the dive (i.e. he needed to add air to the BC), and as Vladimir pointed out, it is good to have a gas reserve in case plan A turns out to be flawed, due to unforeseen circumstances. There can always be unforeseen circumstances (cramping, entanglement, loss of a fin, etc…). Once you have lost one of your redundant devices for getting you safely to the surface, it seems that it would have been more prudent to call the dive.

I guess it comes down to the intended audience of these posts. If I determined that there was a malfunction of my BC when I was overweighted, solo diving with no ascent line, and 50 miles from shore in cold water, I would thumb the dive immediately and deal with the problem on the surface. I think that the majority of recreational divers would feel the same way…