Question about using a lift bag for redundant buoancy

Long story short I went a little crazy with buying gear this winter. I wanted to switch to bp/w from a jacket style to save on the weight I needed to carry. I have plans to get into tech down the road and I like redundancy (who doesn't). So after some discussion with my LDS I put together a set of double 108s. By best guess with the gear change I will not need any weight. I dive wet currently. Planning on getting a drysuit before next winter. But in the mean time I did not get a dual bladder wing for redundancy and since I probably will not have ditchable weight I have a 75lb lift bag bungied to my plate for emergencies. I fully understand this not a ideal situation. But after considering the differences in buoyancy of my old setup to new I am very close to where I should be weight wise. Until the ice thaws and I can do a proper weight check I don't know for sure. So here it is in the unlikely event my wing fails and I am unable to swim my tanks to the surface do I deploy the lift bag on a reel and reel my self up? Or do I clip it off to my chest d ring and inflate it and control my ascent with the dump valve on the lift bag?

Locally where I dive mostly there is a hard bottom no deeper than 72'. I have no intention to dive this setup where a hard bottom would be deeper than rec limits with out a drysuit. Until I can get in the water and do a real weight check I may need more weight making this a mute point. Just to give a little more info in a 7mil 2 piece and jacket bcd I wore 27lbs with a 108. Based on this with bands manifold plus another tank bp and ditching my old floaty bc I will be very close to neutral.

Would it not be simplest to get the dry suit immediately?

The way you're planning it, you need to learn (and practice until you're blue with cold in the water) how to handle an emergency loss of wing lift with the lift bag. You need a lot of practice, because it isn't something you'd use under ordinary circumstances, but when you do need it, you may be trying to manage an emergency situation under a lot of stress.

And once you have it wired, you get a dry suit and have to learn another complete skill. It seems simpler to get the dry suit and learn how to use it as your redundant source of lift. The nice thing about a dry suit is that you can get lots of practice using it to control your buoyancy.

JM2C.

Reg Braithwaite:

Would it not be simplest to get the dry suit immediately?

The way you're planning it, you need to learn (and practice until you're blue with cold in the water) how to handle an emergency loss of wing lift with the lift bag. You need a lot of practice, because it isn't something you'd use under ordinary circumstances, but when you do need it, you may be trying to manage an emergency situation under a lot of stress.

And once you have it wired, you get a dry suit and have to learn another complete skill. It seems simpler to get the dry suit and learn how to use it as your redundant source of lift. The nice thing about a dry suit is that you can get lots of practice using it to control your buoyancy.

JM2C.

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Yes it would be. I just don't have new drysuit kind of money currently(finding a used one that fits has been impossible) Like I said I went alittle crazy buying gear because of the deal I got on everything. I do plan to practice this. Just un sure of the best procedure to follow.

mod8521:

But after considering the differences in buoyancy of my old setup to new I am very close to where I should be weight wise. Until the ice thaws and I can do a proper weight check I don't know for sure. So here it is in the unlikely event my wing fails and I am unable to swim my tanks to the surface do I deploy the lift bag on a reel and reel my self up? Or do I clip it off to my chest d ring and inflate it and control my ascent with the dump valve on the lift bag?

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If I interpret your post correctly, it appears that you a) are suggesting that you think you have a balanced rig, and b) asking which approach to using a lift bag is better. Hopefully you are correct in your assessment, but will have to wait to determine that. As for the lift bag, I have real reservations about clipping myself to a bag, inflating it, and trying to control my ascent rate with the dump.

Although I don't have experience with your setup, I do have experience with a wing failure (see near misses). I always said that by carrying 2 SMBS I could deploy one in the event of a failure (and practiced). However when my wing free flowed and I disconnected the LP and dumped air to stop me flying up - it never crossed my mind to go with my plan. Nor did it cross my mind on the safety stop to orally inflate my wing, I just held onto my buddy. My point is that in times of stress and things happening we react differently to the way we do when practising. But saying that, what else can we do but plan and practise and hopefully if the worst does happen we'll remember.

Simply get the correct amount of weight on your setup. I barelly need to put air in my BCD in order to stabilize at depth. Since you consume your air in your tank you should be able to reach the surface without much lift. I do not really understand what your problem is. By the way, you should also have ditchable weights.

Lift bags work as a redundant buoyancy device. I would suggest getting your weighting right first. In a properly weighted bp/w set up you can swim it up. Doubles are a little harder to get right but still capable. Not much lift is necessary, so this skill is not difficult to master. I have seen this done several ways that all worked, play with it. You will learn this quickly.

Freewillow:

Simply get the correct amount of weight on your setup. I barelly need to put air in my BCD in order to stabilize at depth. Since you consume your air in your tank you should be able to reach the surface without much lift. I do not really understand what your problem is. By the way, you should also have ditchable weights.

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He's diving double 108s...

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I know I cannot swim my double 108s to the surface without some sort of inflation, so I never use them without a dry suit.

I also carry a lift bag on almost all such dives as a second back up, and I was trained to use it as an emergency buoyancy device in one of my advanced technical classes. I was trained to hold the bag under my arm with the other hand on the dump valve. If you shoot the bag with a reel, you will need to have it go all the way to the surface and then reel it in as you ascend. If you clip it off, you may have a potential control problem.

A loss of buoyancy in a wing can be handled with some creativity. A while ago I took my only doubles wing to Mexico, and I discovered it was really too big and buoyant for the AL 80s we were using. The person I was diving with loaned me a smaller and very well used wing. As I was nearing the exit, I reached back and pulled on the rear dump valve to control my buoyancy, and the whole thing came off in my hand. Fortunately, I was in an area with plenty of room and no silt, so all I had to do was go out of trim to keep air in the upper part of the wing. I was about to ascend to the exit anyway, so it was not a problem.

Colliam7:

If I interpret your post correctly, it appears that you a) are suggesting that you think you have a balanced rig, and b) asking which approach to using a lift bag is better. Hopefully you are correct in your assessment, but will have to wait to determine that. As for the lift bag, I have real reservations about clipping myself to a bag, inflating it, and trying to control my ascent rate with the dump.

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A quick break down of my math old setup I needed 27lbs.
New ss bp is -6lbs
New regs is -5lbs
Another 108(empty) -5lbs
manifold and bands -4lbs
old bcd(foam padding) +3lbs
Theoretically leaving a need for 4lbs of lead in new setup. But theses numbers are a estimate. Could be more or less. Seems I will be very close to neutral with out ballast weight. I am not a small guy a lot of neoprene to account for that is why so much weight.
From my limited understanding of a "balanced rig" it would be close.
Yes my question is which approach to using the lift bag in a emergency situation is better. My concern with using a reel was being able to reel myself up when negative. For some reason it didn't dawn on me till now I may only be a few pounds negative with no air in my wing. I was thinking it would be a lot more for some reason. That is if I am close on my math wont know till I can get in the water.

---------- Post added March 23rd, 2014 at 01:33 PM ----------

Freewillow:

Simply get the correct amount of weight on your setup. I barelly need to put air in my BCD in order to stabilize at depth. Since you consume your air in your tank you should be able to reach the surface without much lift. I do not really understand what your problem is. By the way, you should also have ditchable weights.

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Yes ideally I need to add weight which would go in dump pockets if need be. This a what if I don't.