No ditchable ballast

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InTheDrink

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Location
UK, South Coast
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I recently got a twinset, which I love dearly.

The only problem (or at least potential problem) is that I don't wear any weights with it and in fact am a bit negative at the surface. My question really is what strategy you would employ in the event of a bladder failure.

First off, the actual kit I'm using so that I can pre-empt a few responses before they come up.

SS Twin 7s
AL backlplate
40lb wing (single bladder)
No cannister light
Diving wet 5mm

I understand that I could do one or more of the following to address the fact that I have no ditchable weight:
1. Dive dry
2. Get AL tanks
3. Get a double bladder (although I understand this is non compliant)

However I have just spent a ton of money and will not be in a position to get a dry suit or get new tanks until later in the year at earliest.

I also understand that one should in theory be able to swim one's rig up from wherever. This is a theory I haven't tested so I'm excluding this from the possible solutions until I understand whether I can or cannot (by swimming the rig up from increasing depth with the wing empty).

So, back to the original question with two scenarios:

#1. Bladder failure at 30m/100ft
#2. Gas turned off or disconnected LPIH during negative entry from boat.

For scenaio #1 I'm thinking either
a) use the wing in a position where the gas will trap and use this and abort dive.
or b) if the rupture was catastrophic, e.g. the connection from wing to inflator ripped out completely, I'd shoot a bag and use this for the additional lift requirement.

For scenario #2, turning gas on and/or reconnecting LPIH would seem the sensible options. Oral inflate if problem with power inflating.

Any thoughts on these strategies and are there others I'm missing? In all scenarios of course, I would use my buddy if they were around but I'm assuming the worst here and that this isn't an option.

Thanks,
J
 
VJ hit the nail on the head with the alternate buoyancy idea. Since a drysuit is out of the question and I personally don;t like dual bladder wings (just seem so bulky) a lift bag attached to the bottom of the plate is a perfectly valid and useful alternative. Dive rite has a 50lb in a storage pack that can cost from 50-75 bucks dppending on where you get it that stows nicely and is easy to deploy. I woukld advise that if and when you get one that you actually practice with it starting shallow to see just how much lift it has and to get used to working the dump. Another alternative is the DAN safety sausage. It has 40lbs of lift a semi-closed bottom (less likely to lose air if it falls over), and velcro strap handle that allows it to be held in front of you at say waist level and still have 4 feet sticking out. Once on the surface you can if need be ditch the rig. I usually have both.
 
The idea of shooting a bag and climbing up a piece of #24 line is pretty unrealistic, just as hanging for dear life from the strap at the bottom of some bags is highly suspect.

Unfortunately, the only right answer here is to dive a balanced rig, which really means a drysuit with steel tanks, or al tanks wet. Plummeting to the bottom (wherever that is) while trying to equalize your ears and operate some type of lift bag just isn't going to happen.
 
The idea of shooting a bag and climbing up a piece of #24 line is pretty unrealistic, just as hanging for dear life from the strap at the bottom of some bags is highly suspect.

Unfortunately, the only right answer here is to dive a balanced rig, which really means a drysuit with steel tanks, or al tanks wet. Plummeting to the bottom (wherever that is) while trying to equalize your ears and operate some type of lift bag just isn't going to happen.

Well I imagine that given the options forgoing the occasional equalisation would probably be warranted in such a scenario. Although it does create a somewhat amusing picture in my mind - descending to infitinite depth, casually equalising all the while. I might die but godammit I'm going to die with good ears.

I appreciated your point, I really do, however we are talking about the current facts on the ground. I think plummeting anywhere would be a fairly severe indication of overweighting, so I don't think you're on the right track there.

If you're deep when it happens the relative pressure difference will be much less and pain on your ears less, thus giving you time to operate both hands to shoot a bag. I don't see it as quite so improbable as you seem to.

If you're shallow you should be able to swim your rig up.

I agree, there are better solutions to the question but they're not immediately available in the context in which I asked.

Cheers,
J
 
VJ hit the nail on the head with the alternate buoyancy idea. Since a drysuit is out of the question and I personally don;t like dual bladder wings (just seem so bulky) a lift bag attached to the bottom of the plate is a perfectly valid and useful alternative. Dive rite has a 50lb in a storage pack that can cost from 50-75 bucks dppending on where you get it that stows nicely and is easy to deploy. I woukld advise that if and when you get one that you actually practice with it starting shallow to see just how much lift it has and to get used to working the dump. Another alternative is the DAN safety sausage. It has 40lbs of lift a semi-closed bottom (less likely to lose air if it falls over), and velcro strap handle that allows it to be held in front of you at say waist level and still have 4 feet sticking out. Once on the surface you can if need be ditch the rig. I usually have both.

Thanks for the post. I've a standard random SMB, no idea how much lift. However, I don't really put much gas in my wing anyhow for the kind of diving I'm doing so I'd imagine it'd be more than enough for me. And like I say, I'm going to see from what depth I can swim the rig up alone and empty (bladder, not gas :))

BTW - does anyone know why the dual bladder is considered dangerous/uncompliant? It sounds like a reasonable solution with not that much additional overhead. My buddies have them and the additional stowed hose don't appear like a major entanglement risk to me.

Cheers,
J
 
I think what you're really asking for is someone to confirm your belief in the DIR forum.

So you really think that having a ruptured eardrum and shooting a bag while descending is a viable option? You ARE overweighted in a wetsuit with steel tanks, thats the entire issue here. Ever had a ruptured eardrum? I have. It will wreck your day in short order. Trying to do anything while in pain and with vertigo is going to complicate the issue.

You are only slightly negative at the surface, but as soon as that wetsuit of yours compresses at depth, you're going to be quite a bit negative. Thats one foot on the banana peel thats just not needed and is easily prevented by using the right equipment for the job.
 
I think what you're really asking for is someone to confirm your belief in the DIR forum.

That isn't my intention. I have my rig and there is a deficiency and I am asking whether my alternatives to the ideal solutions are adequate or whether there are others. Please try to avoid second guessing people's motives. My motivation, if you must know, is that my fundies instructor asked me to think about what the possible solutions might be to this non ideal situation.

So you really think that having a ruptured eardrum and shooting a bag while descending is a viable option? You ARE overweighted in a wetsuit with steel tanks, thats the entire issue here. Ever had a ruptured eardrum? I have. It will wreck your day in short order. Trying to do anything while in pain and with vertigo is going to complicate the issue.

You are only slightly negative at the surface, but as soon as that wetsuit of yours compresses at depth, you're going to be quite a bit negative. Thats one foot on the banana peel thats just not needed and is easily prevented by using the right equipment for the job.

I've no idea myself, but what rate do you think one would be descending at with complete bladder failure at say 30m? I guess we can assume the wetsuit has lost the vast majority of it's buoyancy. What's that? 6kg (again, I don't really know). So you're now 6kg more negative at 30m. How quickly will that pull you down? Again, I don't know. Is it fast enough that the relative change in pressure in your ear would stop you from being able to deploy a bag/SMB? Again, just questions, I don't know, although I suspect it's not enough to be a huge deal. I certainly haven't had a ruptured ear drum and I'm sure it's pretty excrutiating. I'm still think I could shoot a bag and equalise at the same time. I could of course be wrong, I frequently am.

And if you're shallow, as per my last post, I'm pretty confident in being able to swim it up with the additional buoyancy from my wetsuit.

J
 
Your original question indicated you were willing to purchase a double-bladder wing. An additional $400+/- will get you a used adequate drysuit = problem solved.
 
What PfcAJ clarified in his las response is very true. There is no easy way around it. Neoprene compresses at depth.

I think it would be an easy test do try at, say 70 - 80 feet above solid bottom, with full tanks remove all air in your wing and see if you can hold your depth by finning up, you can then try your lift bag. Be careful not to let it drag you to the surface.

All this said It remains imperious that you dive a balanced rig.

When I started diving twin 130's I bought a dry suit, much $$$ or in your case £££
 
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