Killer Bungee- Myth or Fact

[Walter]

I recall that another argument against them was the rapid loss of air in the event of a puncture (i.e. air being forced out of the wing by the compressing effect of the bungees).

That's the only case I've ever seen against them that makes any sense, even then it should be a minor problem and not a cause of death. You should be able to swim your rig up with a totally deflated BC. If you can't, you need an alternate source of buoyancy.

I've dived them, they worked quite well (the ones I dived had bungies all the way around the wing, not just on the bottom), but the bungies didn't add anything to my dive. Opting for simplicity, I see no compelling reason to use them.

Not to sound like a conspiracy theorist here. But I kind of get the feeling that gear companies, when their not busy inventing gimmicks like fins shaped like whale tails or BCs with elevator buttons, invent ideas like you'll die if you have bungees, some shoulder padding creates drag that will most likely kill you, or using a snorkel to drink beer is a bad idea. Ok, I made the snorkel/beer one up, that actually sounds like a pretty good idea. But seriously, does anyone else ever get the feeling these ideas are kind of created by the people making the gear that is supposed to solve these "problems"?

I doubt it. I think they are legitimate concerns from real divers who point out potential problems with "features." Those concerns are often blown out of proportion by others, usually those who are ridiculing them. For example, the issue with drag and BC padding has never been presented as you did in your post, "some shoulder padding creates drag that will most likely kill you." Shoulder padding doesn't cause drag, any shoulder padding is under the shoulder portion of the BC and therefore in a protected area causing no drag. Padded BCs generally have very little padding in the shoulder, but lots of padding along the back where it is both useless and does create drag. Will this drag kill you? Of course not. It will make you work harder and reduce your enjoyment of the dive. Thanks for the example.

 

[*Floater*]

The myth of the bungee is "true", but you have to take that with a grain of salt. Its true under very specific conditions. These conditions may or may not ever be present during your dive, so there is a very good chance they would never come into play.

For example..if we look at oral inflation and/or "auto-deflate" when a hole is present issues. They will only be true if a) the wing has lots (or needs lots) of gas for the diver to remain neutral and b) the bands are so tight that they are being stretched by the gas requirements of the wing. So the thing is that "Yea..the myths are true", but in truth you might only see them in the lab

Now, the other side of the coin is..."What do the bands bring to the dive". Well, they are there to "contain" the bladder.

Well, my solution was to buy the smallest non-bungee wing (that still meets my buoyancy requirements) because it doesn't have a very large profile and it doesn't have the failure issues that (on paper) exist for the bungee wing. YMMV.

I think JeffG nailed it above.

I've seen tech divers with a ton of equipment dive their rigs overweighted with the bungees very tight. I assume this makes the wings easy to vent in any position and reduces drag/flap. I think those are real advantages for divers who choose to dive overweighted for whatever reason. But by the same token, if one of those wings is punctured, the bungees will squeeze the gas out fast, whereas without the bands you could adjust body position so as to trap the gas in the part of the wing that wasn't puncture. Of course, divers who dive that way, overweighted, often use dual bladder wings or drysuits for redundant buoyancy. For single tank diving with a narrow wing, an Oxycheq Mach V for example, I think the bungees would just get in the way.

 

[daveg1]

I would like to through out a question to those who feel that bungee's will push out the air of a punctured wing.

If that was what happens would the bungee's also force the air out if the inflator when the dump button is pressed, even if the inflator/deflator opening is not at the highest point?

 

[JeffG]

If that was what happens would the bungee's also force the air out if the inflator when the dump button is pressed, even if the inflator/deflator opening is not at the highest point?

Yes it would. But again, the wing would have to be under tension. (i.e. the wing would have to be inflated such that the bungees are being stretched.)

 

[Scared Silly]

How many times have we all heard - if you use/do that you will die? Things get exaggerated ad nauseum especially when it is not liked or perceived to be dangerous. Most times it is not.

That said I do not a bungeed wing but I do have one that is made from an elastic material. It is on my single wing. The material adds very little compression overall. Perhaps next time I am in the pool I will try some experiments - hope I do not die ;-).

 

[JeffG]

How many times have we all heard - if you use/do that you will die?

Never, actually. The only time I see it used is when people complain about it being used. LOL

 

[*Floater*]

I would like to through out a question to those who feel that bungee's will push out the air of a punctured wing.

If that was what happens would the bungee's also force the air out if the inflator when the dump button is pressed, even if the inflator/deflator opening is not at the highest point?

The thing is, well designed wings without bungees are easy also easy to vent when relatively full (when the bungees would be under tension). The tricky part is that last bit of gas out when the wing is almost empty. OMS type bungees would only make that more difficult because they create bulges in the wing that can trap gas and when the wing is close to empty the bungees exert no tension on it. Of course this is not an issue if people who dive overweighted and therefore always have the bungees under tension, but they have to deal with heavier rigs and larger buoyancy changes. Personally I prefer to carry as little weight as I can get away with.

 

[The Chairman]

Actually Walter,

I believe those my OMS Bungeed wings that you dove, and you dove them during the first Wreckmania. In fact, I believe they were punctured at the time and yet, I didn't figure that out for almost a month.

 

[Walter]

Actually Walter,

I believe those my OMS Bungeed wings that you dove, and you dove them during the first Wreckmania. In fact, I believe they were punctured at the time and yet, I didn't figure that out for almost a month.

Pete, I did dive your bungied wings of death at the first Wreckmania in June of 2002. Like I said, "it should be a minor problem and not a cause of death." If they were punctured at the time, it wasn't evident to me. I am curious about one thing, how did you know they were punctured for a month before you noticed?

 

[xiSkiGuy]

Fortunately the "You're gonna die" Crowd has been silent on this thread. We've had some excellent explanations as to how under certain circumstances (diving overweighted with tight bungees and a near full wing) the bungees can be problematic if a failure occurred. What we haven't had is a good explanation for what the bungees add to make a wing better.

We did have this reposted from the OMS site:

# OMS Retractable band BC's assist in deflation *2
# OMS Retractable Band BC's decrease drag when deflated *3
# OMS Retractable Band BC's reduce the massive airshift associated with large non-banded BC's that occur when changing body plane. *4
# OMS Retractable Band BC's have trim adjustability. That is by removing selected bands, differentially inflated parts of the BC can compensate for uneven weight.

The only other "feature" I can think of is that bungees allow you to use a wing designed for doubles on singles without completely tacoing around the tank.

So basically bungees allow you to buy a wing that is improperly sized for your application. Hmmmm. Why not buy the right size in the first place?