My Wing Incident

[PacketSniffer]

Near Miss 11/6/05 - Doha, Qatar

The Near Miss
It was towards the end of a dive-athon for me. The 4th day of a 5 day holiday (Eid holiday in Middle East) bagged me eleven dives at the point this event took place. I mention this because it may have some weight to the issue.

Normally, I take great care of my equipment and religiously do my pre-dive checks. As part of my normal procedure, I inflate my wing with the power inflator and also orally to max inflation. I could tell the wing was holding air from the force from oral inflation and I didn’t hear any leaks. Everything checked out ok before we headed down. My buddies didn’t notice anything out of the ordinary either. So, I was leading a group of five (dive experience ranged from 17 years to several months of daily diving) out to a second reef to do some spear fishing. Upon reaching our waypoint, I set the compass for our destination and we started our five minute fin to the second reef. As I’m cruisin’ along I start to notice that I’m listing to the left (lol). I wonder to myself if the current has kicked up or if my weighting is dorked up or if my wing has more air in one side than the other. I do a couple quick checks and everything is within reason. However, on the wing check, I tilt to one side but I didn’t hear the normal gurgling from inside the wing. I thought to myself, “hmmm”, that is interesting. So, I reach back and come to find out half my wing is void of any air and the other side is pumped pretty good. I’m relieved to have found the issue but now I have to resolve it. My next thought is why none of my buddies, who are following me, have noticed this issue. We reach our destination and the gang begins the hunt for their primary targets. While they hunt, I go through a couple rounds of trying to deflate the wing from the lower pull dump and deflate hose. Nothing is releasing the air. The pull dump is not releasing anything because the side it is on has absolutely no air. Now, I’m a tad concerned. I know I have to resolve the issue before the ascent. I fiddle with the top of the horse shoe wing but nothing is releasing the pumped side of air. I tilt; push the bladder, squeeze the bladder, but nothing is resolving it. By this time, everyone is finished with their hunt and I’m asked to take us back to the 1st reef which is on the way to shore and the end of our dive plan. Once returning to the 1st reef, I know I need to get this situation resolved before going further. It’s also a good place to do it. I ask my buddy to review the problem. He fiddles with it for a couple of minutes. He can’t figure it out. I think I am the first person to dive a BP/W where I’m at. At least they are not at all common around here. Curiosity is killing me so I remove my harness and look at the problem first hand. It looks very strange but I can’t see anything that would cause the air to be trapped on one side. Again, I squeeze, push, and tilt the bladder with the rig in front of me for a couple of minutes. At some point along the way, I realize the air has moved to the side with the pull dump. So, I immediately go for the pull dump and purge all the air. Success! I throw the harness back on and we continue on the route back to shore. I don’t even dare to fill the wing to achieve peak buoyancy for the remainder of the dive back. I leave it void of all air and just use a little more fin/angle.

On the surface, I throw the rig on the back of the truck and begin to review the issue. Without touching anything, I inflate the wing with the power inflator. It inflates just perfectly. Very strange I thought to myself! I had no explanation at the time of what went wrong. However, I was chatting with a dive friend who I relayed the story to. She had brought something to my attention. One potential scenario now has entered my mind. During this five day holiday, I had filled each day with non-stop adventure. The dive day would usually start in the early morning and end with night dives. Sometimes there would be outdoor activity in the middle of the dives and I would never return to the hotel until very late. The previous day of this event I dove in the morning only to hop on an awaiting quad bike to bash the dunes for 8 hours. I didn’t get back to the hotel til around midnight (had to get tanks filled for next morning) and washing the gear seemed a little silly since I was diving right away in the morning. Even though I always leave the wing filled a little, I’m wondering if my lack of nurturing for my beloved wing has caused it to act against me. This is the first time this has event happened to me and I hope it will be the last. It’s the first time I have had a near miss as well. I gave myself another rule and that is, I will at least bring my wing (and regulators) in for a rinse no matter what. I don’t know for sure if this is what caused the event but it seems prudent in light of the potential outcomes.

Options
As I was working at depth on trying to remove the air from the wing, I started to think of my options in case I couldn’t resolve the air issue. My very first immediate thought was that I could always puncture my wing with my dive knife (oooooh, that thought killed me. Hehe). The second thought was to use my spool (100’) and use it to attach myself to one of the wrecked vehicles and control my ascent. The third option I thought of at the surface was to borrow a pound or so of weight from all of the divers in the group. Of course, this option would only work if you were in a large group. A fourth option also thought of at the surface would involve ditching my rig (but tethered with spool) and sharing air with my buddy for the ascent. Just now, I thought of another option which would allow me to ditch only the wing itself (Let’s hear it for BP/W!!). That way, at least I would be on my own air supply. I know not everyone would have that option but my BP and Wing can be separated very quickly and easily *without any* tools at all (no bolts). However, I have that luxury. I have one of Tobin’s rigs from www.DeepSeaSupply.com. It’s a sweet setup and I love it. For the record, I see *nothing at all* that implicates his wing having any fault here. It was just a freak event which *might be* laced to my lack of nurturing during a somewhat aggressive dive schedule.


Lessons Learned
1) Always feel *both sides* to the wing to ensure proper bladder inflation on the inflate check.

2) Always bring wing (and regulators) in for a rinse between dive sets no matter how soon you are diving again.




Richard
…alive and a little more wise

 

[Halthron]

Thanks for the story. I've been wondering about buying a BP/W and part of the process is figuring out horseshoe vs. doughnut and I think that you solved my indecision there.

 

[markfm]

I'd be leery about the borrow a pound or two route -- you would have the bladder expansion with decreasing depth. You might need to have other divers next to you, continuously handing off weight as you rose.

Glad it worked out well. (Also glad, again, that my BCD has both the shoulder and bottom-back dump valves )

 

[dougaldiver]

Sounds very odd to me. Even diving with a wing far too big for the tank all I've ever needed to do was tip head up a bit (to get the air up to the top of the wing) and then roll to the side slightly. Is there any chance that the upper section of the wing, specifically the internal bladder, could have been pinched between the tank and the back plate? Alternatively is it possible that either your reg first stage or hoses could have been squeezing the top of the wing and restricted the air flow?

 

[PacketSniffer]

Sounds very odd to me. Even diving with a wing far too big for the tank all I've ever needed to do was tip head up a bit (to get the air up to the top of the wing) and then roll to the side slightly. Is there any chance that the upper section of the wing, specifically the internal bladder, could have been pinched between the tank and the back plate? Alternatively is it possible that either your reg first stage or hoses could have been squeezing the top of the wing and restricted the air flow?

The upper portion of the horse shoe I was rolling between my fingers. Everything was loose as it normally is. I'm sure it happens, but it's kinda difficult on my rig to get the wing pinched between the tank and plate. Remember, I had the rig off of me and was staring right at it. It was almost as if the bladder was glued closed at the top of the horse shoe bend. Strange...


Richard

 

[dougaldiver]

Yes, the trapped wing was a bit of a long shot.

I seriously doubt that failing to rinse the wing for one day would have caused a problem. I have regularly left a BC on a boat for a two week diving holiday in the red sea without rinsing it (apart from a quick squirt of fresh water on the valves) and you don't dive in conditions much saltier than the red sea.

I would suggest laying the wing flat for a few days, perhaps even put a light weight like a book on the top section. After a couple of days try gently inflating the wing orally (take the weight off it first of course) and see if there is any evidence of the inner surfaces sticking. It may also be worth an e mail to the manufacturer to see if they have heard of anything similar (just in case it's a known fault)

Other than that it sounds like a bit of a fluke and, assuming you have had plenty of previous dives on this rig with no problem I would carry on diving as normal.

 

[DA Aquamaster]

I have seen bladders "glue" themselves together with salt crystals, silt, biological stuff we wil not talk about, etc inside the bladder in situations where the two sides of the bladder are pressed together long enough for things to stick (it's the reason you want to rinse BC's and wings and then store them with a bit of air in them. In the relatively narrow portion of a wing at the top of the horseshoe, this is a possibility and I suspect that high heat, lots of sun, etc could increase the speed at which this could happen. However a full inflation check on the surface before the dive should have identified this problem so I am also quite confused about what could have occurred.

In my opinion a wing should have the pull dump on the lower right and the inflate/deflate hose on the upper left so that you can dump air from either side of the wing if for some reason the sides of the wing are not exchanging gas properly. I get the impression your wing has them both on the left side. This was a problem with my Halcyon wing and was rectified by adding another pull dump on the lower right side.

Adding the other dump will cause some people gasp at intentionally adding another "failure point". (I despise that terminology as many people misuse the concept by only looking at details rather than the system as a whole). I agree adding a dump on the upper part of the wing is a very bad idea, however adding a dump at the bottom of the wing is not a problem as even if it fails you will still be able to trap nearly the full capacity of gas in the wing on ascent. And as you discovered, it's nice to be able to dump gas from either side of the wing in the event something gets stuck or pinched.

If this occurred in a deep/deco situation, you most emphatically would not want to do a polaris missile imitation to the surface, you would most likely not have the luxury of time or gas to mess around on the bottom trying to fix the problem, and you would need your entire rig to get you and your deco bottles to the surface in close formation. In that case if you don't have the other dump, puncturing the bottom part of the wing is about your only speedy option.

 

[PacketSniffer]

However a full inflation check on the surface before the dive should have identified this problem so I am also quite confused about what could have occurred.

The catch here (I probably wasn't clear enough.) is that although I do and did the inflation check, I don't really know for sure that dive if both sides of the wing were inflated. I typically inflate to max (using both power and oral) and because of the resistance at max fill, I understood the wing to be fine, especially since I didn't hear any leaks. It never occurred to me to actually reach back and feel both sides to verify proper inflation to both sides of the wing. That's now part of my procedure. Quick, easy, and simple...

I get the impression your wing has them both on the left side. This was a problem with my Halcyon wing and was rectified by adding another pull dump on the lower right side.

Actually, my pull dump is on the left and the deflate hose is in the center of the horse shoe. It seems that the issue was to the right of the deflate hose.

Adding the other dump will cause some people gasp at intentionally adding another "failure point". And as you discovered, it's nice to be able to dump gas from either side of the wing in the event something gets stuck or pinched.

It's something to definitely think about.

If this occurred in a deep/deco situation, you most emphatically would not want to do a polaris missile imitation to the surface, you would most likely not have the luxury of time or gas to mess around on the bottom trying to fix the problem, and you would need your entire rig to get you and your deco bottles to the surface in close formation. In that case if you don't have the other dump, puncturing the bottom part of the wing is about your only speedy option.

I have never done it at depth but I am fairly confident that I could ditch the wing only in about 3 minutes from doff to don. Definitely, murdering my wing in the begining stages of the ascent would be the way to go though if under a time constraint.


Richard

 

[cool_hardware52]

When I read the first post my first thought was a twisted bladder, but that is very rare, and almost impossible to do on the side with the OPV, because the OPV holds the bladder in place.

It is really not possible to trap the top arc of the wing between the tank and anything else, for a couple reasons: This is above the top of the plate, this is where the tank "crown" is so the tank is smaller at this point, this is where the inflator hose connects etc.

While I have never heard of such a dramatic effect, I have seen plenty of salt filled bladders. I would suspect that the effects of not rinsing, and high temps are the cause of the "glued" bladder.

PacketSniffer, Have you unzipped the wing and looked at the bladder? The urethane is translucent, you should be able to see if you have a cystal build up. Be very careful about inflating the bladder with the wing opened up. The outer wing shell is what limits the expansion of the bladder, like a tire and an inner tube. You can gently inflate the bladder with the wing open, but it might burst before the OPV vents.

Fresh water rinses are of course recommended, for both the inside and outside of the wing. Salt crystal build up can damage the bladder, salt cystals can be sharp, and they will make the OPV sticky.

When I test a wing I inflate it until the OPV vents. This tells me that the bladder is holding air to at least the vent pressure of the OPV, and that the OPV is working.

The urethane we use for our bladders is routinely used throughout the wing and BC market.

What I do to clean my bladder is:
Fill the bladder, through the oral inflate mouthpiece, about 1/4 full of fresh water.
I manipulate the wing so the freash water reaches all points of the bladder.
Drain it out and repeat.
Then I fill the wing with air and orient the OPV to be the lowest point and repeated pull the OPV to drain as much water as possible.
I store the wing about 25% full of air, unless I'm packing for travel, then I roll it up.

BTW, is the reason why an important design criteria was the ability to easily remove the wing from the BackPlate, it makes cleaning much easier.

Let me know if you have any questions or other problems.


Tobin

 

[PacketSniffer]

When I read the first post my first thought was a twisted bladder, but that is very rare, and almost impossible to do on the side with the OPV, because the OPV holds the bladder in place.

It didn't seem twisted....to me anyway.

While I have never heard of such a dramatic effect, I have seen plenty of salt filled bladders. I would suspect that the effects of not rinsing, and high temps are the cause of the "glued" bladder.

This is my suspicion as well. I wish I would have thought about actually looking at the bladder itself before doing anything else. It's not positively identifying the cause that bothers me. It's still strange how everything was fine once on the surface.

PacketSniffer, Have you unzipped the wing and looked at the bladder?

No, I didn't even think about that since it instantly filled perfectly on the first attempt on the surface. Now, I wish I would have thought about that. I rinsed it that night so, I don't know if anything was in there or not now. Dang it...

Fresh water rinses are of course recommended, for both the inside and outside of the wing. Salt crystal build up can damage the bladder, salt cystals can be sharp, and they will make the OPV sticky.

Rinsing at the end of the dive day is part of my normal routine. I soak all my gear in the tub overnight. The wing I rinse real well that night (inside and out). I then drain all rinse fluid, inflate and set it aside. However, the self-inflicted and demanding dive-athon hours allowed me to inject some neglect.

What I do to clean my bladder is:
Fill the bladder, through the oral inflate mouthpiece, about 1/4 full of fresh water.
I manipulate the wing so the freash water reaches all points of the bladder.
Drain it out and repeat.
Then I fill the wing with air and orient the OPV to be the lowest point and repeated pull the OPV to drain as much water as possible.
I store the wing about 25% full of air, unless I'm packing for travel, then I roll it up.

This is exactly what I do at the end a "normal" dive day. Again, even when the dives end at 03:00, I'll be bringing in the wing (and regulators) and rinsing them.

BTW, is the reason why an important design criteria was the ability to easily remove the wing from the BackPlate, it makes cleaning much easier.

It is extremely easy and I love the design. Very slick...


Thanks for the response Tobin.



Richard