Why don't wings have shoulder dump valves?

[happy-diver]

Obviously the bloke never learned to dive old school with no BC.
Would you like a little overweighting anyone?

Man sometimes I would find something to check out in the shallows
and would be carrying half a shipwreck of junk around to stay down.

 

[JohnN]

OMG. I’m gonna die. I’ve put left shoulder pull dumps on both my cold and warm water wings

I personally dislike having to raise my butt and roll to the right to dump air

Thank goodness I no longer dive with split fins

 

[Centrals]

Sounds like the diver was over-weighted as well.

If I have no air in my bc I also sink with a full tank.
Do you not?
The important issue if I can swim up with no air in my bc with a full tank.

 

[SlugLife]

If I have no air in my bc I also sink with a full tank.
Do you not?
The important issue if I can swim up with no air in my bc with a full tank.

There are several factors. Is the person wearing a wetsuit? How much does their gear weight? Do they have a steel backplate, or other heavy gear? Is any of their gear positively-buoyant?

I do not sink when wearing a wetsuit. The only time I've dove without a wetsuit recently was in a pool & I had a steel backplate, no weights, and a 50cu tank, and I sank easily. However, with my 5mm wetsuit, it's a struggle to get down below the surface if I don't have enough additional weight. I typically use 6lbs in addition to my steel backplate, and even then I might be slightly under-weighted.

I agree that a person should be able to swim to the surface with no air in their BC and a full tank, if appropriately weighted.

I also have backup buoyancy devices, but that's perhaps outside the scope of this topic.

 

[hedonist222]

I liked the right shoulder valve on my hydros pro

would use my left hand to pull on it and descend - head almost down

on my xdeep zen, theres only the bottom left one

 

[Ana]

I got a wing from the H church in 1997 and it had a shoulder dump.

It wasn't the pull down kind of valve, I was told that was bad.
The right way to do it was to lift the whole thing up, it reminded me of asking permission at school.
No big deal since I don't use either of the dumps much at all. My wing is empty when I splash and stays empty in warm water. Only gets a few bumps of air at depth when wearing a wetsuit, either valve is fine to get rid of that little air when is time to surface.

If i had my choice i like a shoulder dump with a pull valve. When the wire for the pull corrodes and fails I'll replace it.

 

[boulderjohn]

The short answer "it's an unnecessary possible failure point" is commonly used for many possible pieces of gear, but in many cases it is too simplistic, and that short answer can get in the way of thinking. In scuba, pretty much everything we use is a potential failure point. In evaluating gear as a potential failure point, we should look at the full complexity of the question.

• What benefit does it provide?
• How likely is a failure?
• What harm would come from a failure?
• In total, does the benefit provided make the risk of failure worthwhile?

For any piece of gear, in most cases, it depends upon the kind of dive being done. When I taught OW classes, I was required to use the shop's jacket BCDs, which had all kinds of dumps. When I did my personal diving, I used a standard wing with only the inflator hose and the rear dump. If I were to do a standard recreational reef dive with a jacket BCD with all sorts of dumps, I would not hesitate to use it. The risk of a failure would be very low, and the potential harm would be negligible.

In contrast....

Years ago I was cave diving in Mexico with my standard doubles wing, and it was too big for the AL80 doubles I was using, making it difficult to dump air because of the taco effect. I borrowed a smaller doubles wing, well used. Upon exiting a cave, on the ascent I reached back to dump air, and the entire dump valve came off in my hand. Fortunately, we were near the end of the dive and ascending, so I was easily able to keep enough air in the wing for buoyancy simply by keeping my shoulders higher than my hips. If I had been farther back in the cave and unable to hold that position, I would not have been very happy about that failure. That is a very different situation and calls for different thinking.

 

[-Moe]

It might not be modern, but it's the DIR influence placing the dump on the LHS as opposed to elsewhere. Or maybe it's just the best place to put it.

I prefer mine on the left side because my computer is on my right arm and I like to monitor my depth and ascent rate while dumping air.

 

[SlugLife]

The short answer "it's an unnecessary possible failure point" is commonly used for many possible pieces of gear, but in many cases it is too simplistic, and that short answer can get in the way of thinking. In scuba, pretty much everything we use is a potential failure point. In evaluating gear as a potential failure point, we should look at the full complexity of the question.

• What benefit does it provide?
• How likely is such a failure?
• What harm would come from a failure?
• In total, does the benefit provided make the risk of failure worthwhile?

For any piece of gear, in most cases, it depends upon the kind of dive being done. When I taught OW classes, I was required to use the shop's jacket BCDs, which had all kinds of dumps. When I did my personal diving, I used a standard wing with only the inflator hose and the rear dump. If I were to do a standard recreational reef dive with a jacket BCD with all sorts of dumps, I would not hesitate to use it. The risk of a failure would be very low, and the potential harm would be negligible.

In contrast....

Years ago I was cave diving in Mexico with my standard doubles wing, and it was too big for the AL80 doubles I was using, making it difficult to dump air because of the taco effect. I borrowed a smaller doubles wing, well used. Upon exiting a cave, on the ascent I reached back to dump air, and the entire dump valve came off in my hand. Fortunately, we were near the end of the dive and ascending, so I was easily able to keep enough air in the wing for buoyancy simply by keeping my shoulders higher than my hips. If I had been farther back in the cave and unable to hold that position, I would not have been very happy about that failure. That is a very different situation and calls for different thinking.

Great post. I'd add a few more:

• What ways could it fail?
• How would you manage that failure? Also practice your solutions.
• Prevention - Can any of the failures be prevented, or reduced likelihood of happening? Prevention is important, but not a substitute for ability to manage failures.

For this scenario:

• Stuck open, stuck closed, rip out hose, broken pull-cord.
  
• A redundant buoyancy device and/or not being over-weighted. For example, since I always have redundant buoyancy with a DSMB, sometimes a lift-bag, and my backplate wing is dual-bladder (1x to 3x redundant). Being properly-weighted should allow one to surface with an empty BC, an 80% lung capacity (which can & should be practiced). DSMBs also make a good pool-noodle/life-jacket for surface floatation. For stuck-closed, you have your normal dump-valve & manual-inflate button.
• Prevention: Here, you could double-check that the hose and attachment points are all properly secured & tightened. I'm not sure if oiling dump-valves in a thing, but that might prevent the stuck open/closed scenario. Verifying your dump is activated with the right amount of tug-tension & doesn't rip out with a harder-than-necessary tug. If you're really worried, sometimes there are ways to secure an item more than one way.

 

[AfterDark]

My OMS wing has both, the shoulder dump is on the right and bottom dump is on the left. I never use them, I just make sure they work. The corrugated hose is enough for me.

I do have a Oceanic BCD jacket from the 80's with a pull dump on the corrugated hose that still works, just used it with my double hose last year.