Dual bladder wing?

[SailNaked]

Is this really REQUIRED? I will not be very deep >150fsw or very cold +60° Worst case assuming 2x steel 100s 20# 2 regulators, bands and manifold ~7# 3mm wetsuit -6# (or 6mm @ 12#) so a total of about 21# (no weight belt). I know that I can easily swim up 17# probably more but have not tried yet. worst case is about 27# with total wetsuit compression.
so assuming I jump off the back of a boat and my primary bladder pops or the dump valve disintegrates on impact, I would need to stop my decent relatively quickly or take a trip to the bottom. Seems to me if put about 4-6# permanent positive buoyancy on my kit that I could just swim up in the event of a total wing failure. and then deploy an SMB or lift bag at the surface? Is this sort of plan sufficient? I could of course just go to the bottom complete my dive and then be neutral for the swim up. an alternate plan might be to put my singles wing (32#) in tandem and orally inflate in an emergency. means additional drag and an additional hose.
would tech instructors permit me to dive this configuration? (assuming I could demonstrate the ability to swim up my kit with 0 air in the wing?) and also had neutral buoyancy at the safety stop?

 

[JeffG]

Is this really REQUIRED?

No

I know that I can easily swim up 17# probably more

You can? How do you figure that?

 

[Rainer]

Have you tried to swim up 17# from 150' (much less 27#)?

You want to take a "tech" class, so now try holding some 30+ minutes worth of stops with those 17-27#. Good luck.

Is this really REQUIRED? I will not be very deep >150fsw or very cold +60° Worst case assuming 2x steel 100s 20# 2 regulators, bands and manifold ~7# 3mm wetsuit -6# (or 6mm @ 12#) so a total of about 21# (no weight belt). I know that I can easily swim up 17# probably more but have not tried yet. worst case is about 27# with total wetsuit compression.
so assuming I jump off the back of a boat and my primary bladder pops or the dump valve disintegrates on impact, I would need to stop my decent relatively quickly or take a trip to the bottom. Seems to me if put about 4-6# permanent positive buoyancy on my kit that I could just swim up in the event of a total wing failure. and then deploy an SMB or lift bag at the surface? Is this sort of plan sufficient? I could of course just go to the bottom complete my dive and then be neutral for the swim up. an alternate plan might be to put my singles wing (32#) in tandem and orally inflate in an emergency. means additional drag and an additional hose.
would tech instructors permit me to dive this configuration? (assuming I could demonstrate the ability to swim up my kit with 0 air in the wing?) and also had neutral buoyancy at the safety stop?

 

[DCBC]

Is this really REQUIRED?

When is redundancy ever required? Do you require redundancy? If not the answer to your question is no.

As mechanical devices tend to malfunction and I tend to dive relatively deep at times, I welcome redundancy in all systems. This is not to say that a double wing is a requirement on all dives, as this can be overcome with a dry suit or lift bag if need be. I do however own a double wing and use it in certain situations.

 

[rjack321]

If you are skimping, just use Al80s instead of the steel 100s. They are much cheaper and if its warm enough for a 3mm suit your consumption should be modest. They have enough gas for shallow tech dives, even not so shallow dives if you add bottom stages. You won't be so inherently negative and can keep your single bladder wing.\

BTW you must have tons of insulation if a 3mm suit is acceptable for you in 60F water

 

[SailNaked]

No

You can? How do you figure that?

Because I have done it like I said.

rainer :
You want to take a "tech" class, so now try holding some 30+ minutes worth of stops with those 17-27#. Good luck.

Why would I have stops at this weight? I only weigh that at the start of the dive, at the end of the dive I would be neutral bladder or not.

Rjack:BTW you must have tons of insulation if a 3mm suit is acceptable for you in 60F water

Two different paragraphs, obviously it would not be possible to dive in 60° water with a 3mm, with my 6.5MM semi dry in 60° water I would have more like 12# positive buoyancy from the suit until it compressed at depth. the example is worst case 3mm in warm water steel tanks.

I am trying to ask a serious question, if yall will take a second to think about it I am sure you will see that I will be diving with no more weight than I know I can swim up if my bladder totally failed at the start of the dive. near the end of the dive I would not need my bladder even with a stage.
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? I said I would have a lift bag but I have no idea how that would help if I jumped off the back of a boat fully loaded with a failed bladder by the time I got it out and filled I would be near the bottom(assuming I was unable to swim it up, but if I can swim it up then like I said i would have time to use it).

Again only intend to dive with hard bottoms <150ft. can we limit the "you Going to Die" comments to a minimum. Unless of course I missed something and I am going to die.

 

[ucfdiver]

I love when people start tech diving and try to cut corners.....GREAT idea! I'd use air for that 150ft dive while you're at it.

 

[Rainer]

Because I have done it like I said.


Why would I have stops at this weight? I only weigh that at the start of the dive, at the end of the dive I would be neutral bladder or not.

For a 30 minute dive at 150', I'd use a bit over 80cf of gas. That'd leave more than half your gas in your double 100s. If you were 27# negative at the start of the dive, using up 80cf of gas is only going to take 6# off that total. Good luck doing 30 minutes of deco swimming up 20#.

 

[JeffG]

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?

You could ask one.

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

 

[JeffG]

I love when people start tech diving and try to cut corners.....GREAT idea! I'd use air for that 150ft dive while you're at it.

I love it when they want to learn on the internet, but start out

"I'm a dive stud" so most of the rules don't apply to me. Keep that in mind when you teach me how to dive.