JACKET vs. BACK INFLATE BCDs- which and why?

[Pre BC]

J:

Thank you for posting a question that got so many of us thinking! In addition to the differences in fit and function that have been very well discussed in the previous postings, you should spend some time contemplating what kind of diver and diving you plan on doing. For example:

When I need to travel to little visited exotic locations that require travel by small planes (i.e. light weight & compact) I use a Dive Rite TransPac and the Travel Exp wing. The combination is easy to pack, light weight and provides a stable diving platform. I also bring all the easiest to pack light weight versions of all my gear (i.e. I bring my SEA&SEA DX-1200 because it shoots both good photos and HD video instead of my full Canon 5D photo and Sony HC9 video rigs).

In contrast, when I am diving locations where that are more readily accessable and allow for virtually unlimited gear, I turn into a photo/video nut with bulky overwieght luggage. I then carry both of my underwater photo/video rigs with lighting systems and my BC is the much larger Sea Quest Pro QD. It has tons of pocket space and allows me to carry everything I need for my underwater photo safaris! The gear needs to fit both the diver and the circumstances!

You have recieved tons of great advise/insights about the functionality of 3 major styles of bouyancy systems (jacket, back inflate & BP/W)... Now add to the equation the type of diving you most want to concentrate on and make your first purchase. There is no one size fits all perfect choice for every kind of diving situation. Nor is there a perfect brand... I shared what I personally use purely for illustrative purposes. I think my gear is great because it fits me and my diving. You need to find what fits you and your diving!

P

 

[ToPpS]

I trained with the usual "jacket style" BCDs as part of my OW/AOW/Nitrox courses. After doing a fair amount of research on equipment on-line, which with me means a few months.... I'm bad like that I decided on a Back inflate BCD. Went with the Mares Pegasus in the end purely on a budget reason.

Without getting into to much of a product review. It's a great little BCD. It does the job very well even though it doesn't have all the bells and whistles like the other BCDs on the market.

For me it was also a comfort thing, I never liked the way the jacket squeezes your ribs when fully inflated. Under the water i did find it easier to manoeuvre around and do upside down hovers.
I personally couldn't go back to the jacket style now that I've used a back inflate.

Here's a fun exercise for you. Fully inflate your jacket style BCD and then try get into your pockets.... not easy.

 

[boulderjohn]

OK, I guess that in order to defend all the decent tropical instructors from this snide reply (which added nothing to the conversation) I will have to add two words to the taken out of context quote.

"As a tropical tourist instructor I prefer my beginners to be able to release all the air from their BC's as easily as possible."

Sorry for the offfense. The remark was not intended to be snide. Since I have only used somewhere between 30-40 tropical operations, it was wrong for me to take what I preceived as a widespeard practice and project it elsewhere. I was also thinking more of what I see on dive boats as the DM's help divers with their weighting, since I don't see much actual instruction. As I type I am thinking especially of the slightly built, petite young lady in her 3 mm suit who was given 26 pounds on a boat in Bonaire to help her with her difficulties submerging.

I have also seen the opposite--DM's trying to talk divers down from the ridiculous amounts of weights they request.

I also believe there was some value in what I said, since people can easily deal with air venting problems by being overweighted, and that is what I see far, far more than I see properly weighted people trying to get trapped air out of a BCD.

 

[Teamcasa]

...I am thinking especially of the slightly built, petite young lady in her 3 mm suit who was given 26 pounds on a boat in Bonaire to help her with her difficulties submerging.

I have also seen the opposite--DM's trying to talk divers down from the ridiculous amounts of weights they request.

I also believe there was some value in what I said, since people can easily deal with air venting problems by being overweighted, and that is what I see far, far more than I see properly weighted people trying to get trapped air out of a BCD.

What I see is far more an experience issue, not a gear selection issue.

While it is true that several BP/W users here on ScubaBoard believe their choice is the end-all-be-all of diving gear, just chanting that same mantra in virtually every BC related thread does not make it so.

Overweighed divers are generally new and experienced. Even if they were sporting a brand new BP/W they would still be new and experienced and chances are, overweighed. Clearly, there are countless experienced divers that use a conventional BC, back inflate or otherwise that dive routinely and are properly weighted.

 

[MauiScubaSteve]

boulderjohn; perhaps if the tourist divers had better instruction back in their land locked home towns the tropical instructor/guides would not have to put so much weight on them to get them to submerge, perhaps if the newbs weren't hard sold on back inflate BC's before their diving skills were capable of working them the tropical instructor/guides would not have to put so much weight on them to get them to submerge, perhaps if mainland instructors would all make sure their newbs knew how to get the last trapped air out of their BC's the tropical instructor/guides would not have to put so much weight on them to get them to submerge.

At the down line of the first charter boat dive site is not the easiest place to instruct a newb you thought was a certified diver on how to release air from their BC. You say the petite diver had difficulties submerging; was she given extra weight in incriments until she and her trapped air submerged?

Now after my post along the same lines as yours, can you see how disparaging other people really has no pertinance to the subject of the OP? My similarly denigrating post added nothing to the discussion of which BC to chose; all I did was lower myself to wallow in the gutter slime with you.

 

[djanni]

Here's a fun exercise for you. Fully inflate your jacket style BCD and then try get into your pockets.... not easy.

Surely no one fully inflates their BC while diving. On the surface maybe, yet when you've surfaced you're not likely to be digging around in your pockets. That sounds like a good store demo for someone who's advocating a back inflate over a jacket.

I prefer back inflates but the pocket thing is not an issue.

 

[boulderjohn]

; all I did was lower myself to wallow in the gutter slime with you.

Boy, I never intended for this to take the turn it did. I sincerely apologize for my role I had in this. I assure you I was innocent of any thoughts in the way this was taken, and my apparently poor communication skills caused some unintended harm. I never intended the offense that was taken, and I am sorry that this degenerated to extremities of name calling.

 

[MauiScubaSteve]

I assure you I was innocent of any thoughts

...

and I am sorry that this degenerated to extremities of name calling.

Your "apparently poor communication skills" apparently go both directions, as I have seen no name calling anywhere in this thread (unless this is what you mean by "extremities"); all I did was describe the location of our thread hijack.

I'm still waiting to hear the details of the petite diver; how again does this help us decide which BC to chose?

 

[Slonda828]

OP,

I think you should try all three types (properly sized), and see which one you like. I have a BP/W, which I use for anything challenging or technical (like deep wrecks). I also have a ten year old (non-weight integrated) jacket BC, which works fine for DM stuff as it facilitates wearing a weight belt and demonstrating skills. I've had plenty of back inflation BCs as well, including the venerable ranger and islander. I think the bottom line is that someone telling you which type or model of BC to use on the interweb computer machine has very limited veracity, and that you should place your personal experience far higher. If you lack experience (which is not meant as inflammatory), then do your best to get some before you spend 300-500 dollars. Heck, if you live anywhere near Georgia come by my place and I'll let you try all three in the pool for nothing. Then you can pick which one you like before you invest your money. I always stock good beer too if that helps.

 

[rstofer]

Surely no one fully inflates their BC while diving. On the surface maybe, yet when you've surfaced you're not likely to be digging around in your pockets. That sounds like a good store demo for someone who's advocating a back inflate over a jacket.

I prefer back inflates but the pocket thing is not an issue.

Why wouldn't a wing be nearly fully inflated at great depth with a heavy wetsuit and a full tank?

I can imagine losing 16# of neoprene flotation as the suit compresses and the tank still has 8# of air so even if the diver were perfectly weighted, they would need 24# of lift under these conditions.

If the diver is overweighted, the required lift would increase. That could be pretty close to the total lift of a 30# wing. Most BCs have somewhat more lift. Perhaps on the order of 35# of so. They might not be fully inflated but they are getting close.

As to how this affects the pockets? Beats me! I don't recall having a problem with my old SeaQuest ADVi jacket style BC but all I ever carried was dive tables and a slate. It probably wouldn't be a problem with a back-inflate BC but most of those have integrated weight systems and the pockets are often limited.

Richard