Just a question??

[faye]

I was just wondering what the GUE stance is on redundant bouyancy while diving wet.
Are they in for stacking bladders or what. I haven't really heard it being discussed on the board.
And please, please, please DON"T anyone else come on this thread and turn it into a damb debate over DIR. :upset:
I want to hear from the GUE guys, as a prospective student

 

[MASS-Diver]

I don't think DIR allows for multiple bladders in any situations.

I would think that by diving with the right cylinders and having a balanced rig, redunant bouyancy would not be necessary if diving wet, although a 100light bag is always a good thing to carry.

I'm not sure though, maybe one the GUE trainined divers on the board can confirm this.

 

[MrBlue]

The GUE/DIR stance is that if you 'balance' your dive rig, you will not need a redundant source of buoyancy, as you will be able to 'swim' the rig up to the surface at any point.

This is why AL80's are recommended if diving the ocean in a wetsuit, as they are less negative than a set of steels. The cannister light can be used as ditchable weight (although with a helios setup, you aren't ditching much weight), and it would be a might expensive ditch too Of course a weightbelt would be ditchable weight too.

You should only be negative by the amount of gas in your tanks when weighted properly, more or less. If you can hold neutral with 500psi in your tanks at 15 or 20 fsw and no gas in your wing, you are where you want to be.

You don't need redundant buoyancy (2 wings etc) if you are weighted appropriately.

--Blue

 

[detroit diver]

MrBlue once bubbled...
The GUE/DIR stance is that if you 'balance' your dive rig, you will not need a redundant source of buoyancy, as you will be able to 'swim' the rig up to the surface at any point.

This is why AL80's are recommended if diving the ocean in a wetsuit, as they are less negative than a set of steels. The cannister light can be used as ditchable weight (although with a helios setup, you aren't ditching much weight), and it would be a might expensive ditch too Of course a weightbelt would be ditchable weight too.

You should only be negative by the amount of gas in your tanks when weighted properly, more or less. If you can hold neutral with 500psi in your tanks at 15 or 20 fsw and no gas in your wing, you are where you want to be.

You don't need redundant buoyancy (2 wings etc) if you are weighted appropriately.

--Blue

Well, that answer came right out of the blue

Welcome to the board!

 

[daylight]

Mr Blue has the party line correct.
What I still would like to know is what are you supposed to do if you have a decompression obligation? Riding your lift bag gets unrealistic.

DSAO,
Larry

 

[MrBlue]

daylight once bubbled...
Mr Blue has the party line correct.
What I still would like to know is what are you supposed to do if you have a decompression obligation? Riding your lift bag gets unrealistic.

DSAO,
Larry

How does having a deco obligation affect anything? If your wing catastrophicaly(sp) fails, you abort the dive. So, your deco obligation is going to be less, most likely.

For sake of agrument, let's say the wing fails at your planned bottom time, so you have a deco obligation. You are diving a balanced rig, and you are X number of pounds lighter as you've breathed down your backgas, you're also ascending so you're getting back some bouyancy from your wetsuit (less pressure, less compression, more bouyancy). You also have the option of dropping some or all of your ditchable weight.

You already know that you could swim the entire rig up with full tanks and you can hold 20ft with an empty wing and 500psi in your tanks.

Sure, deco may not be as pretty and effortless, but you are going to be able do deco in that condition.

Finally, what are the chances that a wing will fail so terribly that you can't trap air somewhere in the cell by positioning your body? This will help with added bouyancy.

I carry the party line because it makes sense to me. And, the question was decidedly asked what the party line was....

 

[detroit diver]

daylight once bubbled...
Mr Blue has the party line correct.
What I still would like to know is what are you supposed to do if you have a decompression obligation? Riding your lift bag gets unrealistic.

DSAO,
Larry

BTW, we don't "ride" lift bags. They're for lifting. And SMB's are for marking.

 

[padiscubapro]

MrBlue once bubbled...


How does having a deco obligation affect anything? If your wing catastrophicaly(sp) fails, you abort the dive. So, your deco obligation is going to be less, most likely.

For sake of agrument, let's say the wing fails at your planned bottom time, so you have a deco obligation. You are diving a balanced rig, and you are X number of pounds lighter as you've breathed down your backgas, you're also ascending so you're getting back some bouyancy from your wetsuit (less pressure, less compression, more bouyancy). You also have the option of dropping some or all of your ditchable weight.

You already know that you could swim the entire rig up with full tanks and you can hold 20ft with an empty wing and 500psi in your tanks.

Sure, deco may not be as pretty and effortless, but you are going to be able do deco in that condition.

Finally, what are the chances that a wing will fail so terribly that you can't trap air somewhere in the cell by positioning your body? This will help with added bouyancy.

I carry the party line because it makes sense to me. And, the question was decidedly asked what the party line was....

Not to sound agressive but how deep have you gone in a wetsuit?? a 3mm by 200fsw is basically a skin near ZERO buoyancy. granted you didn't need much extra weight to get you down.. no change that to a 7mm farmer john, again very little bouyancy on bottom, if you are on a drop off you have a serious decision to make.. if I don't drop my wight I'm gonna sink.. if I do drop my weight I'm screwed once I get shallow..

If you dive a Shell type dry suit, buoyancy is pretty consitant throught the dive, if you dive a neoprene dry suit, you need even more lead at the surface than a wet suit diver, if you try and put enough gas in your drysuit to control your buoyancy one wrong position the gas goes out your neck or wrist seals.

Its easy to rig a redundant bladder without any extra failure points.. just don't hook up an inflator... it adds almost no additional drag, and if the SH*t hits the fan just unclip you lp hose and move it to the other bladder... no emergency..

I would NEVER dive steels with a wetsuit without some type of redundant buoyancy..


Swimming up a righ with full tanks depends on what depth you are doing it from.. are you going to test yourself from 250 and see if you can do it?? its one thing trying it at 100, but a different animal deeper.. a 7mm wetsuit is less than 2 mm at 100 fsw by 200 its 1mm... You have half the buoyancy you had at 100 fsw from your suit.. couple this with your BODY being compressed (its not drastic but its measurable) and displacing less water its even worse..

 

[MrBlue]

To answer the first question. Not that deep. 160ish in a 3mm with twin AL80's, is where I'm at right now. Although 90% of my diving is Northeast drysuit with steel twins.

I'm still not completely following your logic though. If you dive a balanced rig and you have thought out failure scenarios, how does depth make a difference on this topic?

With your example of a 7mm suit, it would require me to wear additional weight on a belt in addition to my cannister light. This gives me the ability to shed part of weight in order to become less negative and stop from plummeting to the depths. As I ascend and the suit 'de-compresses' *grin* the weight that I kept on my body would allow me to at least maintain some negative buoyancy and not rocket to the surface, blowing my deco stops.

But, in all honesty, I wouldn't be diving a 7mm suit and would opt for a drysuit and be diving double steels (as that added weight is needed to offset the positive bouyancy of the drysuit and undergarmet).

In any case, If you are diving a balanced rig with your ditchable weight properly distributed, I can't imagine not being able to either a) be able to swimg the entire rig up to a point where the suit is more buoyant or b) drop a portion of the ditchable weight to allow you to swim up. But, I'm a drysuit diver and a weenie tech diver.

It's difficult to take one piece of the DIR system and make a decision on it's merits; such as redundant wings. As the DIR system is whole approach. In this case (buoyancy and gear conifguration) being able to swim up a rig when you have a wing failure, takes many things into account. Proper weighting before the dive, not being overweighted, having proper ditchable weight, knowing how much of buoyancy swing your backgas is going to have, knowing how much 'non-ditchable' weight you need, knowing how much or how little your suit is going to shift in buoyancy, deciding on the most appropriate exposure protection in regards to bouyancy shift, etc... If that makes sense.

I think what you touch on re the 7mm wetsuit, brings up the whole neoprene (7mm) drysuit and the issues with that and why the DIR system says that a shell suit is more appropriate.

I guess what I am saying is that you have to look at the whole setup as the 'pieces' make the puzzle fit together and make sense. looking at the individual 'pieces' of the system just doesn't make any sense. At least that's how I see it.

 

[faye]

Well I am trying to look at bouyancy and how the system deals with this issue, and my situation.
I am diving twin al80
I am diving in a 3 mil, Very little change in boyancy.
Tanks add 6lbs when full
they lessen 6lbs when empty
I need to add six lbs of weight for the end of the dive
I cruise down at the beggining of the dive 12lbs neg.
BOOM
a sword fish makes a wrong turn into my bladder
I am now 12 pounds heavy and have to abort
I CAN swim up 12lbs...I think...I hope...

Half way through the dive
BOOM
My buddy spontaniously becomes - magnatized, and his knife is + charged. My bladder absorbes the projectile.
I am -6lbs

I thinks I could handle a DECO at -6 pounds

Is the second bladder worth the -6lbs DECO???

Correct me if my thinking is off... ussually is though

by the way does the GUE trainning go over diving wet, I would really be interested in "the doing it right" answer?