Questions about Dual bladder wings

[PfcAJ]

Sad and sobering story that everyone needs to read.

 

[danvolker]

Sad and sobering story that everyone needs to read.

Aquanaut Mailing List Archive Service [ link to this discussion on the accident] This has all the language and WWF posturing of the old days, but these were the discussions at the time of the triple death, at a time when tech instruction was POOR, and the practices enganged in by tech divers were often pure personal preference, with no good reason for the preference. George was still reeling from the deaths of Sheck and a few others that he blamed entirely on bad practices being pushed by some agencies and some individuals, so he was pissed about this new death tragedy, and we wanted to prevent another by ripping up anyone possibly promoting more deaths, by foolish behaviors... At least this is the insight I would offer to pretty aggressive and confrontational discussions you would see..... Scubaboard arguements are all "love and kisses" compared to the posts back on Aquanaut

 

[PfcAJ]

I've read a good bit of that stuff. There are some real nuggets of wisdom contained in there. I've learned a a handful of tricks from those old posts.

 

[JamesK]

I prefer a drysuit as my redundant buoyancy. If I do have a run away inflator it is really easy to tell which one it is. You know immediately. Also my wing inflator is right next to my drysuit inflator. I can operate both at once with one hand if need be.

I have had friends on dives with me have their dump valve stick open when they went to dump gas. They were diving a setup like mine, and were able to add air and control both inflators immediately with one hand. Yes, they dropped, but were able to recover quick.

---------- Post added January 26th, 2013 at 10:33 AM ----------

Dan, thanks for posting that link. That incident was before my time, but was still being talked about. Sad. I am going to spend time reading all of that throughout the day.

 

[dumpsterDiver]

In fact, the lift bag redundancy was the solution employed by tech instructor, Andre Smith, in the Divers Supply Tripple Death Tragedy some maybe remember reading about in the late 90's. Andre and 3 students, all geared with heavy steels and stages, and using wet suits on a 280 foot deep dive....One student could not get neutral on the bottom, as his bungie wing kept letting air out through the OPV, before he could get enouhg air in the wing to get neutral.....Andre was heavy himself, and after the first mentioned student ran OOA and drowned on the bottom( without Andre offering him gas), Andre tried to get off the bottom by deploying a lift bag...which got away from him, leaving him too heavy to get off the bottom...There was one single surviver, so we actually know what happened. Andre ended up stripping his doulbles off and attempting a free ascent, but did not make it.
A "balanced rig" would have saved each of them. Dry suits instead of wetsuits would have saved each. The thick wetsuits with heavy steel was stupid. PADI needs to get their collective heads out of their asses and call bad gear combos, bad.....rather than coming up with nonsense like double bladders.

As a P.S... I also just remembered that the survivor also recounted that they were all suffering from hyperthermia on the dive, and he and Claypool barely had the strength left in their legs from this, to swim up to the shallower, warmer water.
Doing the 280 foot deep dives off of Palm Beach in the 90's, we began this with wet suits, but abandoned this after a few months( of course we used balanced rigs even then) because almost 1 third of the dives we would do in the summer would need to be aborted--it would be warm on the surface, but at 200 or so their would be an inversion or something going on, and the temp would be closer to high 50's. You could feel your feet almost instantly dissappearing/going numb, leaving you kicking your knees to make the fins push. In fact, in those early days, I would use a lycra suit as often as a wet suit, since at depth there was almost no difference in warmth. Deco would put the warmth advantage to the wet suit, but the entire bottom time the lycra was nicer because you could use almost no weight at all, so you had very nice bpuyancy and trim simplicity.
We switched to dry suits because having to cancel / abort a dive after all the planning and nonsense time wasting of doing a deep dive day like this, was very annoying.

Dan:

I know that accident was a big deal. However, several of those comments do not jive with my recollection of the accident. Andre stripped his doubles off and tried a free ascent????

As I recall the surviver said that Andre seemed to have run out of back gas, switched to a deco gas and toxed out? That is what I remember of the story.... Plus if Andre has ditched all his tanks as you state.. he would most certainly have floated to the surface... being a rather fat and buoyant person who was not wearing a weightbelt... Instead,,, Andre's body floated up and was located by fisherman maybe 3-5 weeks later off Jupiter. I interpret this to mean that his tanks and harness were still worn after death and excessive bloating and softeneing of tissue allowed the body to slip free of the tank harness and float up.

As for the comment that the OPV value and the bungi wings of death failed to allow the student to ever become neutral, was not clearly established from the survivor's story (per my recollection he was rteported to have expereinced bouyancy problems through out the dive).. This could have been caused by many things. I suspect that this was the key to the entire acident (as much as the excessive weight).. If Andre saw his student having bouyancy problems on a 280 ft dive... the proper response would be to abort the dive then and there. It seems that had that been done, there would have been ample time and resources (lift bags etc) to get the 4 divers safely to the surface without too much trouble.

I used to know Andre and dove with him and he was a reckless fool. Probably poor form to bad mouth a dead guy, but that was my opinion then and it was relayed to his employer through written correspondence from me, well before his final accident.

I don't dispute your claim that this triple fatality was most likely a poster child for balanced rigs, but some of your statements don't seem to jive with my recollection of the story that the lone survivor was supposed to have told.

 

[danvolker]

Dan:

I know that accident was a big deal. However, several of those comments do not jive with my recollection of the accident. Andre stripped his doubles off and tried a free ascent????

As I recall the surviver said that Andre seemed to have run out of back gas, switched to a deco gas and toxed out? That is what I remember of the story.... Plus if Andre has ditched all his tanks as you state.. he would most certainly have floated to the surface... being a rather fat and buoyant person who was not wearing a weightbelt... Instead,,, Andre's body floated up and was located by fisherman maybe 3-5 weeks later off Jupiter. I interpret this to mean that his tanks and harness were still worn after death and excessive bloating and softeneing of tissue allowed the body to slip free of the tank harness and float up.

As I recall, the survivor, Mike Elkins ( I think that was his name), said that intially, Andre signalled Elkins and Claypool to ascend, while Andre tried to get the body up, along with himself. They headed up, as Andre was beginning to pull out his SMB. The two heading up, actually did a see-saw ascent, the computers showing major trouble getting off the bottom and maintaining ascent...Finally they reached around 80 feet or so, and Claypool realized his instructor, and friend, Andre, had not followed them up--and knew that their must have been a problem. Their was no discussion of low air for Andre, I am quite sure Elkins did not see Andre's pressure guage...He made no mention of it that I know of.
When Claypool went back down, the assumption was that his hypothermia was so bad that he was unable to power up off the depth another time.

As to the body of Andre, the investigators and "us", agreed at the time of the body being found at the surface by fisherman, that he must have stripped the rig from his own body--it was not the type of rig you could just "fall" or slip out of. The body had not decomposed to the point of skeletal /structural failure that would have him released from the harness. Whether we were right on this--well, it was conjecture then, and now

As for the comment that the OPV value and the bungi wings of death failed to allow the student to ever become neutral, was not clearly established from the survivor's story (per my recollection he was rteported to have expereinced bouyancy problems through out the dive).. This could have been caused by many things. I suspect that this was the key to the entire acident (as much as the excessive weight).. If Andre saw his student having bouyancy problems on a 280 ft dive... the proper response would be to abort the dive then and there. It seems that had that been done, there would have been ample time and resources (lift bags etc) to get the 4 divers safely to the surface without too much trouble.

There was an enormous amount of discussion about the reasons for the student to have no control of bouyancy. He was not a long time diver....perhaps not more than 80 dives to his credit, but even so, he did KNOW how to reach neutral bouyancy...so the thinking was that the BC was failing to hold air....whether you want to blame this on tight bungees, or bungees getting shorter due to the exceptionally cold water, or to an OPV failure or leak....this IS the reason we dive a Balanced Rig, so a problem like this is a "non-issue". Andre was also "leading" this dive from fairly far ahead of the student that ran OOA( bad judgement on this, as he had no awareness of potential problems with students behind him, that were relying on him) , and his gas use was far beyond that of Claypool or Elkins or Smith. He had complained of not feeling well prior to the dive, and there were just problem, stacked on top of many other problems with this "training incident".

---------- Post added January 26th, 2013 at 03:20 PM ----------

So I just went back to some of the old aquanaut posts....the student that died with Detective Claypool was Elkins..the lone survivor was Larry Roth.
Claypool was actually a very good friend of my brother Kirk--Kirk asked me to help find the body, so that the family would not be destroyed further by the tragedy, by the insurance company refusing to pay without a body. Kirk knew Claypool as they worked cases in common--Kirk was/is a State Prosecuting Attorney. We had the police helping us, anyway they could on our dives....several would go out with us on the boat over the several weeks we spent on this.

 

[rlynch]

To the OP,
When i dive wet (which i do now and again) i only dive tanks i can swim up. For me this means double LP85's with a deco bottle. Anything more and i move to my drysuit (regardless of water temp). I have had a OPV (Dump) valve go missing on my wing at 100+ FSW and swam up my rig, replaced the valve and we carried on with the dive with about 5 minutes lost on the boat. Stuff happens.
I do not see any advantage to managing 2 wings if you can swim up your rig in a wetsuit. The lift bag thing is massively hard to control, and yes it can work but wow is it easy to get away from you. Imagine doing it under sever stress and think about the consequences....
Overweighting divers has caused countless tragedies over the years from the basic OW certs to the tech dives done regularly in South FL and beyond.
The Padi tech program has some other issues as well (not just it but many of the lower level tech courses from various agencies do as well). Frankly if you need dual redundancy b/c you cant swim up a set of tanks buy a drysuit.
I understand that dual redundancy is in the standards and why but this is not a good solution

btw.. most dual bladder wings i see have 2 things in common 1) the second inflator is not hooked up & 2) the second inflator is tucked into the wing bungees (so its useless) even when it is hooked up.

 

[Trace Malinowski]

Before I learned to use a dual lift wing properly I believed a lot of the rhetoric. There are pros and cons to wearing a dual bladder wing just as there are pros and cons to wearing a drysuit and a single lift wing. The pro of a dual bladder wing is that you have redundant lift in a device that is designed to provide lift. Drysuits are not optimal for redundant lift - especially once the diver reaches the surface and is in a vertical position. Drysuits will often burp gas out of the neck seal. Try an experiment and tread water in heavy steel tanks in open water without the wing inflation. Only use drysuit inflation. What happens? Does your suit burp gas? Do you find yourself struggling a bit? A lot? This will depend upon the diver, what size tanks he is using, and the fit of the neck seal.

I've seen a drysuit fail to suspend a student wearing a DUI TLS-350 when the elbow came off the wing's corrugated inflator hose. The team provided the redundant lift needed by assisting the diver to shore not far away. Had this happened in the ocean awaiting pick-up by boat, the diver whose wing lost gas could have panicked or the team may have decided to ditch the entire scuba rig. Some divers have little problem treading water in high capacity steel tanks without inflation in either the suit or the wing. Others cannot. One's physical prowess and diving skill may also come into play when deciding on a single lift wing vs. a dual lift wing.

Diving environment is also a factor. Are you diving in warm open ocean or in caves? Most caves allow you to push, pull, and crawl your way out of with a buoyancy failure and many will allow you to stand up in shallow water at some point near the exit. In cold open water, you are probably already wearing a drysuit. A drysuit plus a dual bladder wing is needless drag. If you are wearing a drysuit then a drysuit and a single wing is a better bet than a dual lift. Ascent is another issue. If you somehow got gas in the second bladder at depth, you'd now be managing 3 devices in which gas would be expanding during ascent - wing 1, wing 2, and drysuit. Not recommended!

How would gas get in the wing? Well, it shouldn't be from an LP auto-inflator hose. DO NOT ... again, DO NOT connect the redundant inflator/wing to an LP auto-inflation hose! Leave the redundant wing as oral inflate only. Before the dive, fully orally inflate the redundant wing and make sure it is working. Make sure the OPV works just like a single wing. Then dump as much gas as you can and inflate your primary wing all the way with the auto-inflator. Dump the rest of the gas from the redundant wing as you do this. The redundant bladder should now be collapsed.

While it is probably true that most wing tears may come in two's OPV failures and corrugated hose failures will normally only happen to one side or another. I will often remove OPV's in classes and most students never notice. Lost corrugated hoses are a different story. If an OPV fails or if the wing tears near the bottom a diver can drop the trim angle to hold gas in the upper part of a wing maintaining lift. A lost corrugated hose or tear on the top of a wing will be far more difficult to manage.

A couple weeks ago my Halcyon Evolve with 40 lb. lift failed while cave diving at Ginnie thanks to the OPV. I was returning via the Lips Bypass and got stuck. After wiggling free I thought a post or manifold had started to leak because I could hear bubbling above me in the tight space. I flow checked, but couldn't determine the source. It wasn't until I got into bigger passage that I noticed my buoyancy was being lost. As I added gas it was just streaming out the OPV. I monkeyed around with it and then it held. Even with a single wing you can find yourself taking a bit of time to diagnose a wing problem. A dual bladder will complicate diagnosis. For this reason, if you need redundant lift you want to try to avoid adding gas at depth or too much gas. If buoyancy is lost at depth you should attempt to control the ascent with whatever gas you save or add in the primary wing. If you cannot do this then add redundant gas orally to the back-up wing and sparingly. However, you should be able to reach both rear dumps simultaneously and vent during ascent. This is no more or less difficult than dumping a drysuit and a wing during ascent.

In a rescue situation, however, the rescuer may find it more difficult to vent gas from two wings. But, this would mean that the diver somehow experienced the need to put gas in the redundant bladder before needing to be rescued. Rescues, though, are rare and messy. My head wasn't totally in the game during my GUE Tech 2 course because my girlfriend of four years broke up with me a day before class. Would you believe I forgot to vent gas from my buddy's drysuit? And, I teach this stuff! What do you think would happen in a rescue in which buddies do not practice rescue skills and now it's real? You'll probably be lucky if most divers keep the airway open. A single wing and drysuit or two bladders would probably cancel one another out as far as complexity under stress if the divers are totally familiar with the way a rig is balanced. "Balanced" doesn't just mean the use of a drysuit and single lift wing.

Dual bladder wings are often shown in the worst images that opponents find useful for propaganda. But, you can find as many terrible pictures of single lift wings with tech configurations. Huge dual lift bungie wings with lots of danglies dwarfing the tanks and their divers are the norm for poorly configured dual bladder pictures. These images are shown the same way hair replacement and weight loss commercials show "before" pictures of clients at their worst angles, frowning or with neutral expressions, and without tans. "After" pictures show clients tanned and smiling from flattering angles. A dual lift wing needs to be properly sized for the cylinders. My Halcyon Evolve 60 dwarfs my AL80's while my Evolve 40 fits the 80's properly. Likewise, without a drysuit, I might wear a Dive Rite 45 pound lift Classic dual bladder wing with steel 85's, 95's or HP100's. The bungie system was removed and I use 12 inch inflator hoses. Since I wear this wet, I use my Halcyon argon bottle strap on the right side of my plate to hold the redundant inflator hose. I can pull the velcro away to free the hose, inflate it, and reach back and stow the hose resealing the velcro.

The rig is streamlined and looks no different than my DIR system at first glance until someone takes a second look and notices the dual lift. It's a standard at PSAI for instructors and students to have either a wing and drysuit or a dual bladder and wetsuit with steel doubles. When my drysuit was FUBAR I started wearing the dual bladder wing and thought I'd hate it. No way! It's really six pros and cons in one hand and half a dozen pros and cons in the other hand as to the suitability of each wing. In flow caves you really are slicker when wet if swimming. A dual bladder in that case has less drag than a drysuit with a larger surface area.

The key is to keep it simple. Remove all entanglements such as bungies from a dual lift wing. Use a lift capacity that is ideal for the tanks you are using. Make sure the inflator hoses are shortened for streamlining in a swimming profile. Secure the redundant hose so that it doesn't hang. NEVER connect the redundant hose to an auto inflator. Practice using the redundant side and dumping gas with your right hand from the rear right dump and corrugated hose. Normally use the BCD from the left side as the working side.

The main advantage of dual bladders is that you would have quality surface lift in the unlikely even of a primary bladder failure. The main disadvantage is that it does add complexity to your rig, but really no more so than a drysuit. A rescue may be more complicated by a right side bladder than just having BCD and drysuit buoyancy on the left.

I prefer to cave dive in steel tanks and drysuit with a single lift wing or wetsuit and my AL80's (no V-weight) with a single lift wing. But, when I do need to dive wetsuit and steels, I like the reduced drag offered by the dual bladder compared to wearing a drysuit. All equipment needs to be well-understood and configured to be used safely.

 

[TONY CHANEY]

Trace just gave the best info pertaining to this as I have ever heard.

 

[fdarden]

Sounds tough? That sounds like a skills issue that you could work on in the pool. It is not that hard to orally inflate a BC.. I remember inthe good old days, students were actually taught this skill. I have orally inflated my BC over 6 times since I got certified. you should try it some time!

\
I wonder if maybe his backup bladder is defective. I dive steel 100 doubles all the time.. I have no issues whatsoever orally inflating, and managing my dive with my backup bladder disconnected completely from any air source. I purposely do not have an inflator hose running to it. To me the dangers of adding another LP hose to my rig, versus having to inflate my backup bladder orally, far outweigh the convenience of a connected elevator button. Manual inflation does not seem to require a lot of special skill.. Im not sure why you guys think this is an issue. I never use the backup wing actively during a dive. Its there for backup. Its as simple as blowing up a balloon. Requires no special skill that I can see other than to know its possible. Oh and to actually dive a set of dubs, and try it. But back to the topic. I dive a redundant bladder wing, and I can only think of one reason not to dive a redundant bladder wing when performing a technical dive with multiple stage bottles and heavy doubles. Cost. Dual bladder wings are expensive. Are they worth it? I think so.