Formula for estimating wing size?

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Dogbowl

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Is there a rough formula for estimating wing size needed if given enough variables, such as wetsuit thickness, tank type, height and weight of diver, salt vs fresh water, etc? Thanks!
 
Very muscular people will be a little negative, but most of are a little on the positive side. So when you add a wetsuit into the equation, almost everyone will be on the positive side.

So with that said, the wing really needs to be just big enough to float your rig without you in it. Estimate how negative your full tank(s) is in the water as well as a BP or anything else you carry negative. That's the minimum lift you'll need in your wing. It never hurts to err on the side of a few more pounds of lift, but that should give you a good idea.
 
I like this post. I dive with a ScubaPro Glide integrated weight BCD. I have been considering a BP/W. One thing that has delayed me is all of the discussion on here related to the different back plates, wings, harnesses, pockets, weight locations, etc. etc. etc. I like the integrated weights because I really dislike weight belts and the affect they have on my back.

I, too, would be interested in a way to figure out just exactly what I need to dive with the CORRECT bp/w setup. I don't want to buy an "experimental" set of gear.

Cheers - M²
:cheers:
 
I figure...

1. 5 lbs for air in the tank.
2. 3 lbs for every wetsuit millimeter compressed. Example... say your 3mm wetsuit compresses to 1mm. Thats a difference of 2mm in volume multiplied by 3 pounds giving 6 lbs of lost buoyancy at depth to be conservative. If you have a 5mm suit, figure it could compress to 2 mm making a buoyancy loss of 9 lbs at 3lbs per mm.
3. Add a couple of pounds in case you are a bit overweighted in case you didn't dial in your buoyancy check exactly or ate a very big breakfast or you're carrying some extra gear.

ETA: this assumes you have done a proper buoyancy check and have the proper weight added (including the tank) to make you neutral at 500psi with an empty BCD.
 
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I like this post. I dive with a ScubaPro Glide integrated weight BCD. I have been considering a BP/W. One thing that has delayed me is all of the discussion on here related to the different back plates, wings, harnesses, pockets, weight locations, etc. etc. etc. I like the integrated weights because I really dislike weight belts and the affect they have on my back.

I, too, would be interested in a way to figure out just exactly what I need to dive with the CORRECT bp/w setup. I don't want to buy an "experimental" set of gear.

Cheers - M²
:cheers:
Actually it is fairly easy if you know what you like and where you plan to dive. Sure you are almost guaranteed to need minor adjustments, especially if you want to mazimize trim, but overall the basic setup is fairly standard.

For example, warm water aluminum tanks and no belt. Steel backplate (I recommend thhe Freedom Contour), trim pockets at waist and possibly bands (I recommend the ones from DGE), and an 18 wing (i recommend the VDH wing). :) If you want to be sure this works will with stills use a 30 wing instead. As for harness in this configuration all you need is the standard DIR unless you have mobility issues and if so there are deluxe option with a quick release. Add a 1 1/2 inch crotch strap, again with or without a quick release and you are set to dive!
 
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Add a 1 1/2 inch crotch

What I want to know is who has been looking at my crotch and telling everyone that it's only 1 1/2 inches? Even if it is true. :) :(

Cheers - M²

:cheers:
 
I like this post. I dive with a ScubaPro Glide integrated weight BCD. I have been considering a BP/W. One thing that has delayed me is all of the discussion on here related to the different back plates, wings, harnesses, pockets, weight locations, etc. etc. etc. I like the integrated weights because I really dislike weight belts and the affect they have on my back.

I, too, would be interested in a way to figure out just exactly what I need to dive with the CORRECT bp/w setup. I don't want to buy an "experimental" set of gear.

Cheers - M²
:cheers:
The beauty of a BP/W system is that it is highly modular and hence, if in your setup there is something specific which isn't ideal it won't be the entire system you are changing.

I have not taken the plunge yet, but I will be purchasing a BP/W system soon for my upcoming tech courses,.

In my opinion you could do just about with any harness, but you need to figure out whether you a want a traditional single harness, or what they call a delux harness which is sometimes two separate harnesses on the backplate with extra d rings.

Black plate preference really comes down to how much you travel, if you intend travel quite a bit then some people prefer al to steel, but in my opinion the weight difference isnt much and you can't really go wrong with a steel back plate.

As for wing lift, traditionally, I have seen most talk about 38 - 45 pounds lift for the basic tech courses with a lift bag as redundancy for back mounted doubles. If you will notice most smaller lift bags with say 18 - 25 pounds of lift are made in such a way that they only incorporate a single tank, so if you are looking at single tank diving then 25 pounds of lift should be sufficient.

Deluxe Harness Systems like Hollis have made integrated weight option addons available to be purchased separately which give you the advantages of integrated weights that can attached to the harness right where you are probably used to in the traditional BCD.

You may already be aware of most of these facts and opinions, I thought I would just give me two cents in case it helps in any way.

Cheers.

EDIT: What I wanted to get at earlier was that in the event you find your wing size too large or too small, you can always just replace the wing with a different size and keep the other wing as a backup or for different diving styles, for example 25 pound wing for single tank recreational diving and 45 pound wing for tech diving, which is what I intend to do.
 
The beauty of a BP/W system is that it is highly modular and hence, if in your setup there is something specific which isn't ideal it won't be the entire system you are changing.

I have not taken the plunge yet, but I will be purchasing a BP/W system soon for my upcoming tech courses,.

In my opinion you could do just about with any harness, but you need to figure out whether you a want a traditional single harness, or what they call a delux harness which is sometimes two separate harnesses on the backplate with extra d rings.

Black plate preference really comes down to how much you travel, if you intend travel quite a bit then some people prefer al to steel, but in my opinion the weight difference isnt much and you can't really go wrong with a steel back plate.

As for wing lift, traditionally, I have seen most talk about 38 - 45 pounds lift for the basic tech courses with a lift bag as redundancy for back mounted doubles. If you will notice most smaller lift bags with say 18 - 25 pounds of lift are made in such a way that they only incorporate a single tank, so if you are looking at single tank diving then 25 pounds of lift should be sufficient.

Deluxe Harness Systems like Hollis have made integrated weight option addons available to be purchased separately which give you the advantages of integrated weights that can attached to the harness right where you are probably used to in the traditional BCD.

You may already be aware of most of these facts and opinions, I thought I would just give me two cents in case it helps in any way.

Cheers.

EDIT: What I wanted to get at earlier was that in the event you find your wing size too large or too small, you can always just replace the wing with a different size and keep the other wing as a backup or for different diving styles, for example 25 pound wing for single tank recreational diving and 45 pound wing for tech diving, which is what I intend to do.

1. 5 lbs for air in the tank.
2. 3 lbs for every wetsuit millimeter compressed. Example... say your 3mm wetsuit compresses to 1mm. Thats a difference of 2mm in volume multiplied by 3 pounds giving 6 lbs of lost buoyancy at depth to be conservative. If you have a 5mm suit, figure it could compress to 2 mm making a buoyancy loss of 9 lbs at 3lbs per mm.

Thank you. I don't plan to dive tech. It is purely for ease of travel. My BCD takes up a lot of room that I think can be compressed with a BP/W. I'm not concerned with checked baggage weight at the moment (it may change), but I do try to stay under 50#. I don't travel with lead or tanks so any gear volume/weight reduction works for me.

3. Add a couple of pounds in case you are a bit overweighted in case you didn't dial in your buoyancy check exactly or ate a very big breakfast

I have found that after a large breakfast I am more buoyant. At least until I get to depth and the ambient pressure on my body wants to compress my body. I've often wondered if a person's stomach and bowels act like the balloon that is used for demonstrating how pressure compresses the air in your lungs. The question is somewhat jovial. I guess I'm not supposed to joke about the compression of gases at depth and whether or not they can be purged. :D

Cheers - M²
:cheers:



Cheers - M²
 
Is there a rough formula for estimating wing size needed if given enough variables, such as wetsuit thickness, tank type, height and weight of diver, salt vs fresh water, etc? Thanks!

Formula? Not really. It is like the question, "How much weight will I need?" Some professionals can look at you and give a guess such that 9 times out of 10 they are close but that really comes with experience.

I like @RyanT response of you want the wing to be enough to float your gear. I'll sometimes put my gear in the water, get in the water, put my gear on. If my gear is in the water without me in it, the wing has to be enough to make the rig float.

@Ankush Mittal response of around 25 pounds for a single tank seem close to me. I dive with a steel plate and steel tank. So I have found 27 pounds is just enough to float my rig. When diving down south I use an aluminum tank and aluminum plate with a 25 pound wing. I probably could have gotten a small wing but the 25 pound wing was on sale and didn't taco around the tank.

For you, because you live near me, if you are interested in trying out a BP/W I could let you try different combinations in a pool. I have aluminum and steel tanks. I have aluminum and steel plates. I have 3 different wings. Send me a private message if you are every curious about trying out some gear. We could probably do it on a pool night with SUCI or one maybe a shop pool on the weekend. The best way to know what you need to join a scuba club and try out other member's gear. :)
 
https://www.shearwater.com/products/perdix-ai/

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