The great back inflate vs. jacket BC debate

[chepar]

I used a Scubapro Classic (jacket style) during OW. My main gripe with it was that I had a hard time seeing anything below my sternum area. However, I did not really feel "the squeeze" that some people talk about when referring to a jacket style BC. It was very stable at the surface - I kind of felt like a buoy.

I purchased a Ranger, which is a back inflated style. I have a much greater area of visibility when looking down, and I like the "free" feeling of the shoulder straps and around my chest area. One complaint I have heard about back inflate BCs is that they tend to push you face forward at the surface. I have not experienced this problem, and while leaning back while at the surface feels pretty stable to me, I admit I felt a little more stable in the Scubapro Classic. The difference for me is pretty minor, though.

However, all things considered with what I was looking for in a BC, I really like the back inflate style better.

 

[Zept]

In tropical waters, I don't think the style makes that much difference, because the only time you have a lot of air in the BC is when you're at the surface. In temperate waters where you have to compensate for wetsuit compression, I can see some advantages to back inflation, especially if you use steel tanks. With back inflation, the bag of floaty stuff (air), ends up on your back, wrapped around the tank. You should be more streamlined and you should find it easier to stay in a horizontal, face-down position. The trade-off is that it can be harder to stay in a head-up position on the surface. Best answer is to try both types and see which you prefer, as Metridium suggested.

Weight integration would enable you to split your weight -- some in the BC, some on a belt. Might be more comfortable.

Zept

 

[Scuba446]

Back inflation will definately push you face down on the surface - it no big deal though, I just had to adjust to laying on my back and swimming/floating while on the surface.

I tried both, and I'd go the BP and wings route...its modular, can grow if you ever want to get into deep, tech, wreck or cave diving, if you want to go to twin tanks, etc. My SS BP also gets 6# of weight off my belt and thats a nice feature. Plus, the has less drag than any of the BC's currently available. Think thats not a issue? Well, its all about energy conservation and technique while submerged. Gliding effortlessly is sure nice...

I found all of the BC's to clutter up my sternum and stomach area so I could not even see my waist or below any longer. Now I can see my waist, legs, feet, etc.

And if you think, as I did, that a BP can't be comfy - think again. Most people make the mistake of judging how it feels OUT of the water instead of the water.

My advice is, try out a BP and wings if you can.

Good luck!

PS You might also want to consider the DIR hose configuration first. Its awesome!

 

[Walter]

I've used both and there are not really any advantages or disadvantages (except for the crotch strap) of one over the other. A single bladder is more streamlined than a double bladder regardless if it's a vest or wings. It does matter if the bladder wraps around your arms or wraps around the tank. The bladder must (assuming weight is the same) be the same volume with either. Try both, see what is more comfortable for you. When using the vest, don't hook the chest strap, you'll be more comfortable. Also, most people use BC's that are too big for them. If the shop recommends a medium, try a small. See how it fits. As for wings, I don't care for the crotch strap, but you might not mind it. As for pushing you forward on the surface, wings can do that, but if you're healthy you won't find the slight tendency difficult to overcome.

Weight integrated vs weight belt. Personally, I hate weight integrated BC's. To switch tanks easily you must remove the weights, which is a PITA (Pain In The Neck). To avoid the PITA of removing and replacing weights you struggle with a BC that is heaver than it should be to work with easily which is another PITA. Sometimes a diver will have a bad back and need to remove their BC/tank in the water. I don't mind taking a weight belt then taking the BC/tank. I will not take a BC/tank/weights as a single unit. I don't need a bad back.

 

[herman]

I have used both and I do prefer a back inflated with intergrated weights. Mainly due to the problems associated with weight belts. Problems like them turning around or slipping down twards you feet. These problems are eliminated with weight intergration. I also like the fact that they are a single unit which keeps you from being "pulled apart", the BC pulling you up while the weight belt pulling down on you. I also prefer a BC over a BP and wings. While I do see their advantages in a some instances, with my diving style, I will never have a need for doubles or large tanks, a single AL-80 will do me just fine. I do however want some of the other "features" a more conventional BC has to offer, a pocket or 2 and quick releases. In any case, there are positives and negatives with any setup. The best option is to beg, borrow or rent several different types, dive them several times and see what fits YOUR needs because in the end, your comfort and safety is all the really matters.

 

[MikeS]

Just certified in April and purchased all equipment with the exception of tanks, here is my 2 cents.

Back inflation versus Jacket Style BC.

I started with a rental jacket style but purchased a SeaQuest Balance back inflation BC and I will never go back. The back inflation did cause some problems in OW class. For a lot of the skills the class was supposed to kneel on the bottom of the pool. The back inflation BC wanted me to be oriented horizontal, which made it difficult. The good news is that when you’re swimming you're supposed to be horizontal.

I also like the fact that no matter how much air you but in the BC the bladder doesn’t squeeze me. My front is also unencumbered, not the case with a jacket style BC, which leaves room for mounting equipment (i.e. sea snips, dive light, pony tank, etc., etc.).

The one thing I would do differently is to look into a backplate (metal plate that the tank and wings mounts to) and wings (wings are a bladder that attaches to the backplate) in lieu of a BC. But on the other hand, the selection of a backplate and wings, by the nature of the modular design is inherently more complex. It may work out better that I’ve sorted out exactly what I want before I bought one. They’re on my list from Santa (but I’m struggling with the being good all year part of the deal).

Weight Integrated.

The Balance BC I purchased is weight integrated and again I’ll never go back. I like to keep my equipment configuration as simple as practical. Think about when your walking down to the water what you have to carry and possibly forget. My philosophy is, other than mask, fins, and gloves, if it’s not connected to my BC I probably don’t need it and will probably forget it anyway.

Additionally, weight integrated BCs typically provide more options for adjusting trim than a typical weight belt. They have dumpable weight pockets (that you can drop to gain more buoyancy in an emergency) as well as additional fixed trim pockets.

Additionally with a weight belt your only option is to drop the entire weight belt. With most weight integrated BCs you have the option of only dropping one pocket.

In conclusion my vote is for back inflation weight integrated, and if, and only if, you can find someone to help you with selection and adjustment of a back plate and wings, take a serious look at them as they don’t cost more than a quality BC and you won’t outgrow it.

Hope this helps,
Mike

 

[dkerr]

I started with a jacket style but never really liked it. Recently moved to a back inflate w/ integrated weights. The issue of pushing your face in the water when on the surface is often a matter of putting too much air in. Remember, with proper weighting it should take very little air to stay on the surface. If I find myself starting to go forward I just dump a little air and all is well.
As far as integrated weights-preferance. It does complicate gearing up as you can no longer put the BC on the tank while standing and switching tanks can be a pain. If your strong enough then it will not be a problem. If you have issues putting on the BC reg and tank as it is then the integrated weights will just compound the problem.
Try some different styles. Search the board for more info. If you are unclear of any terms just ask (we were, are, and will be ignorant without our questiins answered)

 

[Stone]

Originally posted by dkerr
. . . Recently moved to a back inflate w/ integrated weights. The issue of pushing your face in the water when on the surface is often a matter of putting too much air in. Remember, with proper weighting it should take very little air to stay on the surface. If I find myself starting to go forward I just dump a little air and all is well.

In addition to dkerr's "too much air" comment, some (most?) back-inflate BCs have an easy way to balance your weight to minimize the face-forward effect. For example, you can put weights into pockets in the back (under the shoulderblades) of the SeaQuest Balance to help you float vertically at the surface.

 

[MikeFerrara]

I have preferred a back inflate from the moment I tried one. Since switching to a back plate I will never again dive in a bc of any kind. Why?

Lets talk about what is required to achieve correct trim first, then streamlining.
If our center of gravity (neg buoyancy) and our center of buoyancy (pos) are in exactly the same spot we can effortlessly maintain any position. This is because there are no apposing forces. This is what we want. In contrast, if those centers are different, you have apposing forces pulling you one way or the other. That is why, when over weighted, divers tend to be head up and feet down. The weight is on the waist and the air is above the waist pulling the diver into a head up position. This also explains why a back inflate pushes you face down on the surface if…you are over weighted and the weight is forward of the bladder. In the same situation when using heavy steel tanks you might be forced onto your back. How do we put together a system that comes close to placing the two centers in the same place? With the tank neg we want our weight as close as we can get it. A wing does this. A jacket that puts air all around the diver can never achieve this. Now we still may need to add weight (thick wet/dry suit and aluminum tank). Where do we want it? We want it as close as we can get it to the bladder. A back plate (it has weight) can help here. If more weight is needed we want to add it to the plate. That way all the weight is in the correct place (next to the bladder). If we keep our detachable weight to minimum (belt or integrated pouches) we minimize apposing forces. Keep in mind that our body and exposure suite will also effect where our center of buoyancy is. We may have a floaty bottom or top. One way to compensate is to move the entire system up or down. The harness allows us to do that. Lengthen the straps and everything drops down. Tighten the crotch strap and all the slop is taken out. To achieve what we want we must have the crotch strap. Note that a floaty bottom will allow you to get by with more weight on the waist. Now we have a balanced rig where the tank is not flopping around and we are trimmed. This system will not push you on your face at the surface.

In reality it is tuff to get it perfect. But if the difference in centers is front to back and minimal, like with a heavy tank (the bladder is still slightly forward) as long as we are horazontal in the water we are ok.

If you dive very warm water with little exposure protection you may be near neutral and add very little weight. As far as trim you may be OK even with a jacket and a belt because you never have much air in the bc. Add exposure protection and weight and watch everything go to hell in a hurry. Every day I see warm water divers come to our cold water and flop around the whole dive. They even get hurt. They work to hard, collect CO2, over breath or free flow their warm water reg, they freak and bolt for the surface. The deeper they go the more suit compression and the more air in the bc the worse the whole thing is.

Streamlining means reducing drag. A jacket that allows water to flow in as you move forward acts just like a parachute. We normally don’r deploy a parachute until we wish to stop. A back plate and properly shaped wing does no such thing. Divers tolerate being out of trim and not streamlined because they don’t know what it is supposed to feel like. The difference is dramatic. The drag that is introduced by a hose that loops out away from your body is much more than you would think. Correctly routed hoses are important to the system described above. Also, getting rid of the instrument counsel, that very much resembles a canoe paddle, is an important step in the right direction.

Add to this learning to stay horizontal, good buoyancy control and good fining technique and you will amaze yourself. BTW when trim and streamlined it will be much easier to control breathing making buoyancy control that much easier. Throw one thing out of wack throws a second thing out of wack in turn throwing the first thing further out of wack. Get the idea?

If you carefully examine all the points I have mentioned you may find your mind already made up. Don’t be discouraged by instructors and dive shops that don’t understand this. They are just perpetuating what they were taught. If you teach it to them they might start to carry the equipment you need.

 

[pediatron]

I just finished the classroom/pool portion of my open water course and go to Lake Tahoe next weekend to do the open water portion. I hated the rental equipment and really want to get my own ASAP.

I loved the feel of the Diva LX in the shop, but have had no experience with back inflation. This BCD is descibed as a hybrid, but I don't really know what that means. I also don't know what the practical difference in the water is between a vest infaltor vs. a back inflator (does it push your face into the water at the surface? I saw one post of a newbie having a lot of trouble adjusting to the back inflator when they were learning. Is it difficult? I wish I could try it on in the water or even inflated, but the only dive shop in my town that carries it are NOT easy to work with (and very expensive). Any advise both on this model and on back/hybrid inflation vs. vest would be greatly appreciated!