BP/W - what's the go with air movement in the wing?

[MauiScubaSteve]

Divers have more "Control" in the water with a BP & Harness than any other set up on the market. First off the BP keeps you more horizontal and in trim. Secondly, the wing mounted behind you helps as well.

But what if I want to swim on my side? And I have both vest and BI BC's where my trim is correct, so what improvement in trim could there be? I occasionally go through tight caverns where the roof is scraping my tank, but not my vest; with a wing the scraping roof is way more dangerous! For me I prefer to be in control rather than the rig being in control.

Oh, I see later that you are a BP/W dealer...

 

[gxtoast]

If you are using a buoyant 7mm suit I would recommend a Stainless plate. The dry travel weight of a SS plate vs a aluminum or Kydex plate is onkly about 3 lbs more.

The advantage is the ballast it provides up over your buoyant lungs.

Thanks, Tobin. Even though I was entertaining the idea of purchasing a 'travel' plate, the heavier SS did appeal to me more, and your comment about weight over the lungs has caused me to reconsider.

I am interested in attaching my weights directly to the back plate and not having any attached to the harness. The concept of having the weight close to both the wing and lungs is most appealing in its logic, and in the perceived freedom of movement it will allow.

It is strange that the BP/w manufacturers are not focusing more on a weight system that has the weight closer to the lungs, as you suggested. I am surprised there aren't quick release weights that can be attached to the back plate (as opposed to the topside of the tank, which potentially might make the tank 'back heavy'). Something like the Aqualung Sure-Lock mechanism could be used, but with a ripcord guided over to the front of the harness.

Or, perhaps some kind of moulded lead modules that are shaped long and with a triangular cross section, to run down the side of the tank and which clip onto the centre part of the wing. Located to the sides of an where an STA would fit. Close to the body, close to the wing, not stacked on the tank. I understand that simplicity is key in the BP/w approach, but surely this kind of thing could be refined until it was simple and robustly implemented?

Anyway, I digress.

All I need to decide now is whether or not to go a HOG harness or some custom, adjustable-on-the-fly job.

 

[Diver0001]

This is not a question I have seen asked or answered on these forums before.

One of the things I experienced recently, using a rented jacket BCD, was the movement of air from "top" to "bottom" or end to end (depending on my position). This was disruptive and somehow the movement also caused buoyancy problems, in that it was difficult to stay neutral at times. Odd, considering the air was just moving around.

Anyway, looking at the wings used on backplates and harnesses, it seems that air movement might also be a problem for these devices in that they also have a single bladder. Air must move around the bladder when it is only partially inflated.

Has anyone had any experience with this issue, or is it something that does happen but is not disruptive.

Cheers,
Nick

This is a common complaint when the jacket is too large. It's not the air moving around that's causing your balance problem, but the tank is literally rolling back and forth on your back and might even end up hanging askew.

The wing isn't the solution. This is just a problem with correct fit and adjustment of the BCD.

R..

 

[Tortuga68]

It is strange that the BP/w manufacturers are not focusing more on a weight system that has the weight closer to the lungs, as you suggested

Several BPW manufacturers offer weighted Single Tank Adaptors. Also trim weight pockets on the cam bands which are pretty close to the BP ie about as close to your lungs as you can get on that side without major surgery

All I need to decide now is whether or not to go a HOG harness or some custom, adjustable-on-the-fly job.

Not sure if by on-the-fly you mean during the dive - why would you need to do this? - or between dives when changing exposure protection- in which case the Hogarthian harness is fairly easy & quick to adjust

 

[gxtoast]

Cheers, tortuga68. I have just found that DSS have weighted plates which secure against the back plate.

Halcyon make a harness that can be adjusted in the water while diving:
Cinch Quick-adjust Harness | Halcyon Dive Systems

as do other manufacturers. It seems that most offer HOG harnesses and their own custom harnesses.

 

[Sas]

Ah, looks pretty slim. I've heard nothing but good things about the DSS gear. Same with the OxyCheq gear.

Yep, the wing I was using in that picture was just a rental though sadly I thought it was a very nice setup and I liked that with this BP/W the backplate was heavier than normal due to optional weights that DSS sells that stick to the backplate. Shifting more weight there is handy imho. But yea I already bought my own BP/W setup before trying this one, my replacement will be DSS though!

 

[Tortuga68]

Halcyon make a harness that can be adjusted in the water while diving:
Cinch Quick-adjust Harness | Halcyon Dive Systems

as do other manufacturers. It seems that most offer HOG harnesses and their own custom harnesses.

If you're going to be regularly switching between tropical, temperate and cold water (and therefore changing between various dry and wet suits) and using the same BP/harness, I could see an adjustable harness like the Halcyon Cinch being worthwhile. The Halcyon system has the advantage of being a continuous harness and therefore complying with GUE rules and avoiding unessesary failure points

Personally I don't plan to do GUE and only change between no, 3mm and 5mm wetsuits (mainly 3mm) and so stick with the Hogarthian harness and the KISS method

 

[cool_hardware52]

Thanks, Tobin. Even though I was entertaining the idea of purchasing a 'travel' plate, the heavier SS did appeal to me more, and your comment about weight over the lungs has caused me to reconsider.

I am interested in attaching my weights directly to the back plate and not having any attached to the harness. The concept of having the weight close to both the wing and lungs is most appealing in its logic, and in the perceived freedom of movement it will allow.

It is strange that the BP/w manufacturers are not focusing more on a weight system that has the weight closer to the lungs, as you suggested.

Been there done that, years ago. I prefer keeping the added ballast close to the diver.

For single tank, cold water diving I would however caution against securing all of your necessary ballast to your rig. This often results in the minimum wing size being larger than would be required if ~6-8 lbs of ballast is carried on the diver's person, i.e. weight belt.

The smallest safe wing needs to be able to float your rig at the surface with a full cylinder, and it needs to be able to compensate for the maximum change in buoyancy of your exposure suit, which ever is greater determines the minimum wing capacity.

Lets assume your suit is +24 lbs (this a just an example)

If you mount 100% of your ballast to your it has to provide ~24 lbs of ballast when your cylinder is empty. Add the weight of your gas ~ 8 lbs for a 100 cuft cylinder and your rig is -32 lbs. This requires a wing greater than 30 lbs.

OTOH if you put 6-8 lbs in a weight belt your rig is only 24-26 lbs negative with a full tank, making a 30 lbs. wing a reasonable choice. This 6-8 lbs also provides an easy means of getting the diver positive at the surface in the event of a buoyancy failure.

A medium SS plate and harness is about -6 lbs, a reg is about -2 and the typical empty steel cylinder is ~-2, and -10 full (HP100) That makes the basic rig -18 with a full tank, and it provides about 10 lbs of ballast when the cylinder is empty.

Add 8 lbs weight plates and the rig is -26 with a full tank, and provides 18 lbs of ballast with an empty tank, leaving 24-18 = 6 lbs in a belt.

Hopefully it's becoming clear that wing selection, and suitability of the weight plates is largely dependent on the buoyancy of your exposure suit.

I always recommend testing the suit if you are uncertain of it's actual buoyancy.

All I need to decide now is whether or not to go a HOG harness or some custom, adjustable-on-the-fly job.

My standard advice is to stick with the simple harness. With a bit of adjustment and practice these work for the vast majority of users.

If you find you absolutely have to have a quick release you can buy a buckle and have the local shoe repair sew it in. Very few ever actually do this.

Tobin

 

[Wayne at DiveSeekers]

But what if I want to swim on my side? And I have both vest and BI BC's where my trim is correct, so what improvement in trim could there be? I occasionally go through tight caverns where the roof is scraping my tank, but not my vest; with a wing the scraping roof is way more dangerous! For me I prefer to be in control rather than the rig being in control.

Oh, I see later that you are a BP/W dealer...

1. You can still swim on your side if you want but because the wing is on your back. I find that the air shifts faster than with a jacket thus keeping you more stable when you shift. With a 360 wing, that air shifts top & bottom for faster response as well, oppose to coming up and around ("U" wing). With a jacket style there is a delay in the air shifting around the BC coming to the high side. With that delay you will actually dip down further then come back up.
2. The wing is still relatively close to you back so if you are scraping you tank with a jacket, you will be doing the same with BI. If you are doing tight swim throughs you have a higher risk of puncturing you BC. With a jacket, you puncture it you are done. Depending on what wing you go with, they have inner changeable bladders so in the unlikely event you were to puncture you BC you can just get a replacement bladder that would be at the fraction of a cost of a whole new BC. * Just another plus to a wing setup.
3. Yes we are BP & Wing dealer. From a dealers perspective, you are not keeping current with the sport if you are not stocking BP & Wings! As well as, stocking different models so that you can help people with different price points. BP & Wing is the #1 BC in our shop and that is mainly recreational divers. We have a pool, so once they put that on, they don't even want to go back to a Jacket Style BC.

 

[rstofer]

I am interested in attaching my weights directly to the back plate and not having any attached to the harness. The concept of having the weight close to both the wing and lungs is most appealing in its logic, and in the perceived freedom of movement it will allow.

It is strange that the BP/w manufacturers are not focusing more on a weight system that has the weight closer to the lungs, as you suggested. I am surprised there aren't quick release weights that can be attached to the back plate (as opposed to the topside of the tank, which potentially might make the tank 'back heavy'). Something like the Aqualung Sure-Lock mechanism could be used, but with a ripcord guided over to the front of the harness.

Two things to consider: First, it is good to have a few pounds of ditchable weight. In a rescue situation where you still have a full tank and a blown wing (you jumped in from a boat and the inflator elbow fractured (completely fictitious)), you will be between neutral and somewhat negative. In a perfect world, you could ditch some weight and float a little higher in the water.

Second, and equally important to us old people: if you put all the weight on the rig, the thing is too heavy to lift! A 43# tank, 14# BP, 2# reg totals 59# and there would still be a need for several pounds on a weight belt. If that weight is mounted to pockets on the rig, it would be pushing 70#. Too much for me! I carry 18# of lead in a DUI Weight & Trim Classic harness and use just the 6# DSS backplate. That keeps my rig around 50# - much more manageable. Yes, I know I can load the waist pockets after donning the rig but that just means more diddling around while I burn up in my wetsuit.

And maybe you need some weight low on the hips to counteract the buoyancy of the lower part of the wetsuit including the legs. The DUI recommendation is that the top of the weight pouches be at the same level as the top of the hip bone. Pretty low!

Richard