Using SMB For Backup Flotation

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Alternatively, bag or sling a pony, so in a situation like this you could ditch all your gear and ascend using only the pony. Won't work if the pony is hard-mounted to your tanks, which is why I say bag or sling it.

Also, I would think that, as long as you had a spool of some sort along with your SMB, you could shoot the bag normally and kind of crawl up the line once it's deployed and floating (like everyone has said, you certainly wouldn't want to attach it to yourself on the way up!).

>*< Fritz

Fritz, respectfully.... Adding another piece of gear to address the shortcomings of another dosn't solve the fundamental problem....
 
I'm trying to think through where I'd need this... I jump off the boat into a bottomless void and my BC instantly blows up and I am unable to drop any weight and am not in good enough shape to swim up 12 pounds...

It's not as bizarre as it sounds, since a lot of pull dumps are actually pretty fragile as are some of the corrugated hoses.

OTOH, I'm guessing that anybody with the ability to do a mid-water bag shoot while plummeting to their doom can probably just tilt the hole away from "up" and add a little air or ditch some weight.

Terry
 
Rick makes another point that I overlooked...12# isn't much to swim up, especially if you've got air left to breath and fins on. I'd go to the pool on base and throw in my belt with 28# of lead on it, dive down to the 16' bottom, put it on and swim up slick. It was a bit of an ass kicker, but if I could do it ten or twelve times in a half hour and chase that with a few laps, I can't imagine less than half the weight with fins and increasing buoyancy as you get shallower due to your wetsuit losing compression would be any more difficult..Granted not everyone's on the same fitness level, the fins do add a certain level of "cheat" to the scenario. I'd definitely question my equipment choices if I couldn't swim the rig up in an absolute emergency.

I have to agree with the idea of shooting a bag and climbing the line being the most reasonable if swimming it isn't an option, and definitely offers a much more controlled ascent, because when I'm fighting weight to the surface I'm probably not going to be super concerned with ascent rate.
 
The best way to resolve these questions is to just get in the water and try various approaches. I plan to do that at the earliest opportunity.

Still, it's worth looking at the equipment configuration, reviewing the buoyancy numbers and realizing that there is an issue. In the end, the solution may be trivial but until the question is posed, there isn't a hint that there is an issue. How many people are diving wet with HP 100s or HP 120s and have never even considered the problem?

Thanks Again!
Richard
 
As others have stated, you need something with the dump valve on the top of the bag, so you can control the ascent. You do NOT want the thing attached to you.

Of course you don't want it attached to you. You want it attached to a line, which would be attached to a reel or spool, so when you inflate it it goes to the surface and then you ascend on the LINE.

Instead, puff a little air into it to stand it up then slide your arm through the straps,

Umm, I though you didn't want the bag attached to you? (PS - note they aren't STRAPS.)
 
I'd go to the pool on base and throw in my belt with 28# of lead on it, dive down to the 16' bottom, put it on and swim up slick. It was a bit of an ass kicker, but if I could do it ten or twelve times in a half hour and chase that with a few laps, I can't imagine less than half the weight...would be any more difficult...

I think you'd be surprised.
 
Of course you don't want it attached to you. You want it attached to a line, which would be attached to a reel or spool, so when you inflate it it goes to the surface and then you ascend on the LINE.

I wonder if the line should reeve through a carabiner attached to the front of the waist belt (at the scooter ring?) to prevent the line from getting lost when the reel slips off the fingers. Hold the reel below the carabiner. Clearly, the tail of the line wants to be tied to the reel. I'm thinking about a finger reel that holds 150' of line. That's far deeper than I plan to dive.

Over analyzing again... I do that a lot!

But, again, this is a last ditch process. The wing is blown, the weights are ditched, the diver is tired and can't swim the remaining weight. Staying down until the air runs low and the buoyancy is increased doesn't seem like a good idea.

Richard
 
I wonder if the line should reeve through a carabiner attached to the front of the waist belt (at the scooter ring?) to prevent the line from getting lost when the reel slips off the fingers. Hold the reel below the carabiner.

Why would you purposely entangle yourself in the line?

If you drop the reel it will go straight down. The line will still be right there. Worse case scenario is the reel or spool goes all the way to the bottom and you pull it back up.
 
Why would you purposely entangle yourself in the line?

If you drop the reel it will go straight down. The line will still be right there. Worse case scenario is the reel or spool goes all the way to the bottom and you pull it back up.

I'm thinking of the situation where the line gets fouled on the reel or whatever and goes to the surface or at least out of reach of the diver who can't ascend. If I lose that reel or line, I am in serious trouble.

The line would just pass through the carabiner, not be attached to it in any way. The line would run free until it ran out and the reel jammed up against the carabiner. But that's not likely because I have no intention of diving that deep. And, if I do, I'm not going to worry about being pulled up to 150' below the surface!

It would seem to me that I would rather be entangled with a line that will pull me off the bottom than to lose the line and stay on the bottom. An uncontrolled ascent just seems better than no ascent.

Richard
 
I'm thinking of the situation where the line gets fouled on the reel or whatever and goes to the surface

Help me understand how the line is going to get fouled in a way that when it slips out of your hands it goes to the surface. Do you have some sort of positively buoyant reel?

The line would just pass through the carabiner, not be attached to it in any way. The line would run free until it ran out and the reel jammed up against the carabiner.

A line with a reel/spool on it which passes through a carabiner IS attached to it, by definition. It merely has some play in it. (OK, could be as much as 150') Don't want to open this as its own can of worms, but there's a reason that carabiners are called "suicide snaps" in some circles.

Even if you don't consider having the line run through a carabiner to be "attached" just think about all the other problems that are made possible by having a line run that close to your body. Plenty of places for that thing to get entangled. Suppose you needed to turn to look for your buddy or otherwise re-orient yourself? A reel/line should be an arms length away from you if at all possible.
 
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