Have you ever had/seen BC failure requiring ditched weights?

[urbantchr]

To take the wing failure question one more step, and help decide wether to dual bladder or not.
Who has seen, or experienced a wing failure requiring ditching weights, and what was the failure?
Sorry I'm new and don't know how to set up a cool survey page

 

[doctormike]

Ditching weights is something you do on the surface in case of injury or other emergency. They really aren't meant to be ditched at depth.

Your rig should be balanced in such a way that the wing is really doing only what it's supposed to do. It's a buoyancy compensator, which means that it's there to compensate for two things - the negative buoyancy of the gas that you breath over the course of the dive (about 6 lbs in an AL80), and the compression of your exposure suit at depth.

So ideally you should have no gas in your wing when you are at your safety stop at the end of the dive. If you lost the wing function at the very beginning of the dive, you should be able to swim up the extra weight that the wing was compensating for (negative buoyancy of the gas weight and the wetsuit compression).

 

[Robert H. Diver]

If you are properly weighted you shouldn’t have to ditch even with a failure.

 

[Eric Sedletzky]

I have never seen anyone ditch weights in an emergency, yet.
Back in the day when there were no BC’s, the common protocol when you got in trouble was to dump your weightbelt and bail out to the surface. It was taught to put the weightbelt over your rig straps/crotch strap for easy dumping.
That was a hangover from the skin diving days when dumping your belt was standard procedure for bailout. It still is for freediving.
However, they also didn’t do safety stops and divers would routinely just go up after a dive or when air ran low if they were within NDL’s. Now days of course a three minute stop is pretty much standard (but still not required).
We also have BC’s and with more modern science, dumping weights at depth is very much frowned upon and not recommended. Some people use a drysuit for secondary buoyancy, and others rely on proper weighting so they can swim up their rig from any depth. There are many ongoing heated arguments here in scubaboard about what proper configurations are, etc.

 

[inquis]

My inflator came off the wing in Cozumel after splashing. As I am weighted to be neutral at the end of the dive at the safety stop, I was about 3 lbs negative on the surface at that point. A slightly larger than normal breath kept me afloat. The DM screwed it back on, but cross threaded, so it didn't hold air at depth. I just pulled the rig around in front of me while drifting along at 40 ft, neutral with breath control, rethreaded it, and got on with the dive.

The wing should compensate solely for air left to breath and wetsuit compression. If breath alone is insufficient, dropping weight equal to the air I still carry allows me to ascend and make a safety stop, perfectly neutral just as normal.

In that case, I would still have to kick to compensate for wetsuit compression. At most for me, that would initially be 15 lbs (assuming completely crushed, which is pretty unrealistic) for my 7mm one-piece suit, which is easily done.

To summarize, I don't think you need a redundant bladder for recreational diving IF properly weighted.

 

[Jeff_O]

My inflator came off the wing in Cozumel after splashing. As I am weighted to be neutral at the end of the dive at the safety stop, I was about 3 lbs negative on the surface at that point. A slightly larger than normal breath kept me afloat. The DM screwed it back on, but cross threaded, so it didn't hold air at depth. I just pulled the rig around in front of me while drifting along at 40 ft, neutral with breath control, rethreaded it, and got on with the dive.

The wing should compensate solely for air left to breath and wetsuit compression. If breath alone is insufficient, dropping weight equal to the air I still carry allows me to ascend and make a safety stop, perfectly neutral just as normal.

In that case, I would still have to kick to compensate for wetsuit compression. At most for me, that would initially be 15 lbs (assuming completely crushed, which is pretty unrealistic) for my 7mm one-piece suit, which is easily done.

To summarize, I don't think you need a redundant bladder for recreational diving IF properly weighted.

This slightly off topic. I found those plastic fine threads on BC can cross thread easily. I found that having the BC in such a position that the threaded part you are tightening is from below. It just seemed that I could more easily get everything parallel aligned this way. I have to say when cross threading, you might not really know it. After using this method I found it had to have been not cross threaded as there was less resistance turning. Only when sinching tight the screw cap did I notice something. I was cautious not to over tighten.

 

[BRT]

A buddy with a big steel tank found he had no gasket in the BCD inflator hose at the start of a dive. We had already done several dives with the BCD so we have to assume the dive shop disassembled it, but don't know. I took it apart on the bottom and discovered the seal missing so I brought him up with his weights. If he had not had help he would have had to ditch his weights. 7 lbs of air in the tank at the start of a dive made him pretty negative.

 

[BoltSnap]

Never had to ditch weights, or any thing, at all in my 50 years of diving. Never had equipment failure of any kind while in the water. I had fin and mask straps break but they were caught before I went into the water usually at home before I drove to the dive site. I check my equipment thoroughly before diving and not leave anything for chance. If I am not diving with students, I am diving alone and in both scenarios I don't leave anything to chance for I can't afford any failures (I have redundancies also).

 

[Bigbella]

In over four decades, I’ve known of no one who has intentionally jettisoned their weights, whether from weight integrated BCs or belts; though have known a few people who have accidentally lost weight belts, at depth, either from squeeze or buckle failure.

In my first class, there was only one rig with a cobbled together bladder, one that the instructor demonstrated — what was once called a “Mae West — the rest were either plastic or metal packs, with coarse nylon straps. In an emergency situation, we were instructed to ditch the weight belt and swim toward the surface . . .

 

[BoltSnap]

who have accidentally lost weight belts, at depth, either from squeeze or buckle failure . . .

Or Velcro failure