Vest-style BCD better for buoyancy???

[amg]

I’m just about to make the switch to a BP/W (or possibly other Back Inflate BCD), but now I’m thinking that a traditional vest BCD is probably better for buoyancy.

Let’s agree that much of the time, you want to be in a true horizontal position. When in that position, any air in a vest-style BCD will be in the back part of the BCD anyway (unless the BCD is close to fully inflated) and will help to keep you horizontal, just as in a BP/W or back inflate BCD.

But when I’m diving a wall or pinnacle, I often want to be facing the view, either by swimming somewhat on my side (rather than flat towards the bottom) or floating along the wall at a heads up angle, rather than just keeping my head turned. Likewise, if I’m scanning around for things in the blue, it seems more comfortable to be either be sidewise or more vertical, rather than doing everything with my neck.

With a vest-style BCD, when you roll sidewise, some of the air goes to your top side, helping to keep that position. A BP/W would tend to want to roll you back to horizontal position. When angled up, a Vest style BCD may give you a little air on your front to diminish the effect of being somewhat pivoted back down by air that was just on your back.

There are also times when you want to be even more vertical, such as while waiting for a boat on a choppy surface or when going upside down to look under a low ledge with even less chance of churning the bottom, For these, a vest will make things a little easier than resisting the pivot from having all the air on your back.

I’m fully onboard with the other benefits of a BP/W, such as the ability to mix/match or replace individual components, switch out wing sizes, the use of a steel plate as a substitute for other weighting (when travelling with it isn’t an issue), reduced amounts of materials in the shell, etc.

I’ve just been thinking that a) the ability for some air to move towards your sides and front when you have chosen not be horizontal is actually an advantage of the old-fashioned BCD and not a disadvantage and b) that (assuming weighting is similar) when you are horizontal, an old-fashioned BCD’s buoyancy isn’t making it harder to stay horizontal.

Quite happy to be convinced otherwise.

 

[Alekseolsen]

So, I've never dove singles with a wing, but with doubles, there's not a single issue with staying in any sort of trim/tilt or upside down for that matter.

Quite sure you've just been very much overthrowing the topic

 

[inquis]

With a vest-style BCD, when you roll sidewise, some of the air goes to your top side, helping to keep that position. A BP/W would tend to want to roll you back to horizontal position.

The wing wraps around the tank, so air would flow to the top side in a wing as well. Practically speaking, the tank mass wants to roll you further, which is made worse by the jacket bladder.

 

[Jim Lapenta]

Anything you can do in a vest, you can do in a BPW, provided you are properly weighted to begin with. I never had an issue remaining upright, swimming sideways, upside down, or horizontally in my BPWs.
The amount of air in the bladder should be enough to keep you neutral. Period. No more.
If turning on your side finds the rig wanting to turn you back over, there's too much air in the wing and you are using too much lead. Or you have it in the wrong places.
Old-fashioned BCs, true ones, didn't have a bladder at all. There was a harness, backpack to hold the cylinder, and you had to be correctly weighted because the suit and lung volume provided buoyancy.
Later, horsecollar-type bladders were added. But not for neutral buoyancy. They were to get you to the surface in an emergency.
They began to be used for buoyancy to some degree as time went on. I have one here with an oral inflator.
When the stab jacket came out, it was to stabilize people in the water who were starting to dive and didn't have the benefit of training with proper weighting. \
The jacket is ok for some. For me, I hated it. It was cumbersome, restrictive, and most infuriating had crap where it didn't need to be or pockets that were just shy of useless.
A BPW will let you be in any position you want to be and be stable in that position.
As long as you use the correct amount of weight and put it in the right places.

 

[inquis]

When your weight distribution is correct, you can be head up (or down or flat) with a BP/W or jacket with equal ease.

I think you are conflating two issues: usually jackets are more buoyant, requiring more lead to be neutral, which is typically placed at the waist making you rotate to be substantially head up if you stop kicking. While this can be corrected on a jacket with tank band-mounted trim pockets, a BP/W already has more mass up higher and promotes better trim "out of the box". Make no mistake: one can have good/stable trim with either.

 

[happy-diver]

The air, and not much of it, is there to keep you at a your chosen depth, within a few metres, up or down
then use posture physicality and skill to select an angle of attack, trim, and swim to where your eyes look



Not all like hanging in a basket suspended under a balloon

As an aside, some fiddle with their inflators 10-20-100 times, I try for five or ten

Quite happy to be convinced otherwise.

With all your theoreticals I'm wondering if you are you the boy in the bubble playing tricks on us

Hey I'm happy, the best of health to you

 

[GreggS]

I dive a back inflate BCD and I can get into any position I want. I like that I don't have that wrap around "hug" feel I get with a jacket style BCD. And as stated by @inquis above, I don't get the roll I did with a jacket style, either.

 

[Rilelen]

I prefer a jacket BC for recreational diving, and do find its easier to maintain “out-of-trim” body positions in it for sustained periods of time.

One of often touted benefits of BP/W is that it “helps” the diver stay in flat horizontal trim. That same help also makes it less comfortable (doable, but less comfortable) to maintain other positions in my experience. Same for back-inflate BCs.

Not good or bad; I understand the strong push towards backplates, but at the end of the day if you’re recreational diving for fun, what matters is finding something feels good and works for you. For some people (most people even) that may be a BP/W or back-inflate BC, but there are folks out there who prefer a jacket. Nothing wrong with that.

 

[happy-diver]

A jacket certainly works for me

When I'm not in a wing

Yeah same photo, again, and so it shall continue but I don't dive with anyone anymore, sniff sniff, whaaaaa

 

[Blackcrusader]

I've had both but went back to a Scuba Pro Black BCD and am really happy with it.
Only thing is I am a large chap and have the largest BCD. IT's massive compared to small BP/W

Anyway once on a boat or in the water I really enjoy my BCD. I love the back shoulder pockets for weights so I can get into any position I want. perfectly horizontal is not always what I want. When diving along a wall I will move a bit away from the wall and go vertical just hanging and letting the current push me along.

We already had a thread on being horizontal. lol Me on the right.

THE "PERFECT ( being horizontal ) TRIM" HOAX

I often get into discourse with people who see my videos and go oh so you changed from horizontal and are not in perfect trim. My reply is that whatever position I am comfortable in is perfect trim for me. I hate that restricted view and get a sore neck from being in the "perfect trim" position...

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