Dumping Air Under Water

[boulderjohn]

IF you simply remember that air wants to head up toward the surface at all times, it will help you understand what is happening. If air does not come out of your rear dump, it is because the air is somewhere higher up in the wing. That means your butt is too low at the time.

 

[scubaozy]

Not even when you initially submerge?

Actually that is when I least need the use of inflator, right shoulder quick release will work faster. I use the inflator mostly if I am teaching or want to remind others to dump gas.
Inflator is more usefull if you want to really fine tune, release gas in smaller bursts. A beginner will need more practice in fine tuning with quick release as it requires a gentle pull.

 

[inquis]

With the hip dump, you would ideally pull the string toward the surface, which is "rearward" relative to your body (when horizontal). This moves the valve away from the low point (next to you). I see some pulling laterally or even downward (since the string is dangling) when first learning this skill.

FWIW, during most of the dive I find the roll is unnecessary until I've breathed down to reserve pressure. (I have a doughnut wing.)

 

[BoundForElsewhere]

I thought this was going to be about farting under water. Since I'm already here anyways, if I need to fart, I reach back and play with the butt dump cord on my wing to make it (kind-of) seem like I'm dumping air when the bubbles fly.

Haven't figured out how to make that work for diarrhea, though.

 

[BRT]

Using the inflator dump is good when on the surface so that all/most gas is let out of the BCD and you sink more quickly for the first few metres/feet. You can dump if flat on the surface using the hip dump, but this often leaves gas in the BCD so you may need to fin down a bit until the remaining gas in the BCD is compressed.

Thereafter you’ll be diving flat and using the hip dump.

Pull your shoulder dump!!

 

[BlueTrin]

I find that even in flat trim, I don’t need to pull hard the inflator to dump.

Just curling it backwards further behind than your neck will be enough to dump usually. May not be true on all wings.

Learned that recently during a class and I find it particularly useful when the bottom is not flat and you want to match your trim with the floor and end up head slightly up. But it works for me even when in flattish trim.

 

[Seaweed Doc]

There's lots of ways to get air out of a BCD or wing. Many of them don't involve a knife and permanent damage to the unit.

I'll add one more I'm surprised hasn't been mentioned. When horizontal, rotate your left shoulder up a bit and use the shoulder dump.

That said, I tend to use whatever is seems better in the moment. I also dive dry most of the time and these days use the suit for almost all underwater buoyancy and trim control. Because I have to rotate the left shoulder up a bit to dump air from the suit, my inclination is to also rotate that way to dump air from the wing.

 

[PEDiver]

Feel like people are making this unnecessarily complicated. Use whatever method is best in a given situation. It's as simple as that.

 

[PACKRMAN]

I add shoulder dumps to all my wings

The fastest safest way in an emergency

Do you like this?
I have seen two broken elbows and a few hoses pulled off. Have you had any issues?

 

[JohnN]

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I add shoulder dumps to all my wings

The fastest safest way in an emergency

+1 for this. It may make me a princess, but I really don't like to go slightly head down and roll to get air to dump from the bottom of the wing.

I leave the inflator under a loop on the left harness strap. A gentle pull on the hose fixes those little trim problems