Dual bladder wing?

[Blackwood]

I love when people start tech diving and try to cut corners.....

Then you should read this thread.

warning for the phrase following the second comma.

 

[rjack321]

You could ask one.

The only course that I have heard that requires that is the PADI Tech courses.

I am pretty sure he'll be able to find an instructor who's ok with his double 100s, single wing, and 3mm wetsuit (or 7mm semi-dry smushed to 2mm at 150ft). I've actually seen this configuration (although it was 104s and a nearly fully inflated bungied wing at the end of the dive I might add) in the warm freshwaters of Peacock I.

The OP might have to ask around, but eventually someone will take him on as a student. The short bus is really really short.

 

[BlueWaterDiving]

I would like to know how hard you breath swimming up with no air in your wing. Lets say from 100' Can you do it without working? Is it a job to do it? I would think so.

 

[Red Sea Shadow]

Are the rules so inflexible that a tech instructor will refuse to train me because I do not have a dual bladder or dry suit?

Normally agency standards mandate redundancy. You can do that by dual bladder wing, dry suit, or a suitable lift bag.

 

[PfcAJ]

The double bladder wing isn't going to do anything in the situation you described. Here's why:

The 2nd bladder would be disconnected (reasons can be found elsewhere). You just aren't going to be able to stop your descent and connect the 2nd LP hose to your 2nd bladder. You're going to plummet to the bottom because swimming 30lbs up is a real feat, and every foot you descend, you lose more and more of you wetsuit buoyancy. Bad news.

If you had a drysuit (better for cold water anyway), you can inflate that and slow/stop your descent and control you ascent.

150 feet is a long way, and while you might be neutral at 10 feet with empty tanks, your tanks will probably never be empty at any time. Manifolds simply do not fail with any type of regularity while diving. Having a simple way to achieve neutrality is the answer here, and this is best addressed by a drysuit. I can ascend and maintain a 20ft stop with JUST my drysuit and 104s, which certainly aren't lightweight tanks.

You need to be able to hold stops at any point during the dive. At 150ft for 20 mins, you're still looking at a 20+ minute ascent to deco out properly. Your tanks certainly won't be empty, and swimming up weight for 20 minutes isn't something I'd want to do.

Ignore the "agency mandate" thing and really think it through. The double bladder thing doesn't hold up to all the situations that a drysuit does and adds equipment thats not really needed. Steel tanks with a drysuit or lightweight aluminums with some sort of ditchable weight (can light is a great one) and a wetsuit is the move.

 

[Red Sea Shadow]

Ignore the "agency mandate" thing and really think it through.

Ignoring the "agency mandate" thing is agency standard violation isn't it?

 

[PfcAJ]

What of it?

Agencies often advocate all kinds of baffoonary, take a look at the PADI drysuit course. They teach the DS to be used as primary buoyancy. Agencies have deep air programs and solo diver classes, two things that are know to cause problems time and time again, yet they still exist as actual courses.

If an agency says "oh, its cool to use double wings or a lift bag as you backup if a wing fails," but that practice doesn't hold up to scrutiny, then ya, ignore that stuff. Just because someone says its ok doesn't mean it really is.

 

[DCBC]

Agencies have deep air programs and solo diver classes, two things that are know to cause problems time and time again, yet they still exist as actual courses.

There certainly seems to be a big change in the degree of competency of divers today. It's ok to certify a diver with 100 dives to be certified to do a 300 foot dive on Trimix, but there's a danger to do a 150' dive on air?! Rubbish. There's nothing the matter with deep air if the diver is prepared properly and not rushed along in the process.

If an agency says "oh, its cool to use double wings or a lift bag as you backup if a wing fails," but that practice doesn't hold up to scrutiny, then ya, ignore that stuff. Just because someone says its ok doesn't mean it really is.

I have used a redundant wing and the second bladder is never disconnected. When a dry suit is used, I use a single wing. When it isn't on deep dives, I'll use the double. Perhaps you might explain how "the practice doesn't hold up to scrutiny."

 

[ucfdiver]

I am pretty sure he'll be able to find an instructor who's ok with his double 100s, single wing, and 3mm wetsuit (or 7mm semi-dry smushed to 2mm at 150ft). I've actually seen this configuration (although it was 104s and a nearly fully inflated bungied wing at the end of the dive I might add) in the warm freshwaters of Peacock I.

The OP might have to ask around, but eventually someone will take him on as a student. The short bus is really really short.

I wouldn't use ANYTHING done in N FL as justification on how to dive!

Ignoring the "agency mandate" thing is agency standard violation isn't it?

So was diving double tanks in the cave at the intro level in NACD cave courses not too long ago...would you suggest following THAT standard?

There certainly seems to be a big change in the degree of competency of divers today.

So why put a lesser skilled diver at a disadvantage with a convoluted gear setup?

It's ok to certify a diver with 100 dives to be certified to do a 300 foot dive on Trimix, but there's a danger to do a 150' dive on air?! Rubbish.

You're putting words in people's mouths. I have a problem with either one. Besides, going to 300ft on trimix with 100 dives is a different issue than going to 150ft on air. One is lack of experience, one is failure to use technological advances to make diving safer.

There's nothing the matter with deep air if the diver is prepared properly and not rushed along in the process.

Other than the death toll....I would post a list of diving deaths with an END greater than 100ft from 1990 or so until 1997, but moderators deleted my post last time I did that (you can find it on aquanat archives). It was at least 200 names.

I have used a redundant wing and the second bladder is never disconnected. When a dry suit is used, I use a single wing. When it isn't on deep dives, I'll use the double. Perhaps you might explain how "the practice doesn't hold up to scrutiny."

Having 2 wing inflater plugged in is a great way to have an uncontrolled ascent and not know which one to stop (or at the very least, delay your figuring it out).

 

[PfcAJ]

Pete Gelbman had an incident where he didn't identify and correct an autoinflate situation. He was NOT diving a dual bladder wing, however, the ascent started and was unable to be controlled. I believe he suffered a serious type 2 hit.

Having two bladders connected doubles your chance of failure and also reduces your chance of identifying th problem (which bladder) and solving it before its too late. A wing autoinflating feels and sounds different than a drysuit autoinflating, giving you additional information to help correct the issue.

In terms of wing puncture, whatever caused one for fail probably got the other, as well, especially with regards to pinch flats.Thats yet another example of the double bladder argument not holding up.

You don't always need more gear to solve a problem. Often the answer is to use the correct gear for the situation at hand.

And DCBC, don't put words in my mouth. I never said either of those two things were smart. I said that deep air wasn't smart. A novice diving to 300ft is just as dumb. Deep air (or high ENDs past 100ft) has contributed to the deaths of plenty of skilled divers. Its a shame that so many agencies still think that air can be "handled" or dealt with, when time and time again, it gets people hurt or killed. What keeps people alive is good skills, a great buddy, smart gear choices, and using the proper gas at the proper depth.