phoenix31tt
Contributor
as a person that switched from standard jacket to bp/w fairly recently, i would say go horizontal and pull your butt dump valve... it's the most effective way for me to sink in a rear inflate/bpw type configuration
Problem with back-inflate bcd
- Thread starter mnjhuz76
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+1. I do that in a jacket BCD, too: more natural trim during descent.
claymore
Contributor
I will make guess that with a 65# bladder you are getting air trapped in the wing. The 911 has a huge bladder and can easily trap air. My 44# bladder has issues at times with trapped air. I would suggest staying vertical for the first 10 to 20 feet, lean way to the right and get the inflator way up high on decent. The 911 was not designed as recreational BC. It was designed as a Search and Rescue, Public Safety Diver BC.
OP
mnjhuz76
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Training won't overcome the drawbacks to an improperly sized BCD ... although it might help you learn to live with its limitations.
There is never a need for a BCD with that much lift in single-tank recreational diving ... for comparison, I used to dive double 119's with two deco bottles and a scooter with a 60-lb wing, and it was more than enough lift for all of that gear. A singles wing rarely needs to have more than about half of the lift you're currently using. And the larger the wing, the more difficult it will be to vent without trapping air ...
... Bob (Grateful Diver)
OP
mnjhuz76
Contributor
There goes the Zeagle then... Fortunately I can still return it 
claymore
Contributor
Don't feel to bad. I have known several people who have made the same mistake and bought way more BC or the wrong BC for the intended use.
The Chairman
Chairman of the Board
I have a few students get caught with this from time to time. Weighting with a full tank, all air removed and legs crossed should result in your head being just awash (just under). Then, when you exhale, you'll descend until you take the next breath. At this point your descent will be arrested until you, and here is the magic, exhale again.
If you want to descend faster point your head down and remove drag. If you think that there might still be unwanted air in your BC, get vertical, put your Deflator in your mouth and gently suck on the end while pushing the deflate button. Be careful of any water that might be in the corrugated hose or the BC itself. I actually do this before I splash if I am doing a hot drop on a wreck.
Remember: cross your legs and don't exhale until your head is just under water (awash).
If you want to descend faster point your head down and remove drag. If you think that there might still be unwanted air in your BC, get vertical, put your Deflator in your mouth and gently suck on the end while pushing the deflate button. Be careful of any water that might be in the corrugated hose or the BC itself. I actually do this before I splash if I am doing a hot drop on a wreck.
Remember: cross your legs and don't exhale until your head is just under water (awash).
My gf has always had some issue at the beginning of the descent. She never has realized that she just slightly, instinctively kicks ( to stay vertical) as she was trying to descend, which pushes her back toward the surface ever so slightly. She kept trying to solve her problem through weighting, she was absolutely certain that she was NOT kicking, and nothing I said could get her to consider that kicking was a part of the issue.
It was not until she was taught to dive a BP/W, and learned to do her descent face down using the butt dump valve, that this problem disappeared completely.
Before you sell the wing, you might try laying face down in the water, and dumping the air from the rear or butt dump valve. If you do kick while you are in the horizontal position it will not push you toward the surface at all, but actually help you descend. It is far easier to do controlled ascents and descents while horizontal, and if you tip the hip closest to the butt dump valve just a bit high, your wing will quickly dump every bit of the air it holds, far better than the shoulder dump valve tends to do.
Just a suggestion.
It was not until she was taught to dive a BP/W, and learned to do her descent face down using the butt dump valve, that this problem disappeared completely.
Before you sell the wing, you might try laying face down in the water, and dumping the air from the rear or butt dump valve. If you do kick while you are in the horizontal position it will not push you toward the surface at all, but actually help you descend. It is far easier to do controlled ascents and descents while horizontal, and if you tip the hip closest to the butt dump valve just a bit high, your wing will quickly dump every bit of the air it holds, far better than the shoulder dump valve tends to do.
Just a suggestion.
Ayisha
Contributor
+1 From a horizontal position, pull the bottom dump as you're lifting your butt higher, especially toward the the side you're dumping ie) make the dump the highest point
You can pull as little or as much as you want to descend slowly or quickly
When you are trying to descend, exhale looooong and slooooow; then inhale slightly sharp and quick; then exhale long and slow again; repeat.
Try it and see how efficiently you can descend. If your exhale and inhale cycles are the same volume and length, it will be hard to get anywhere.
You can pull as little or as much as you want to descend slowly or quickly
When you are trying to descend, exhale looooong and slooooow; then inhale slightly sharp and quick; then exhale long and slow again; repeat.
Try it and see how efficiently you can descend. If your exhale and inhale cycles are the same volume and length, it will be hard to get anywhere.
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