Wing Size Suggestions...

[Rainer]

I heard Fundies instructors really like 85# dual bladder wings.

 

[Rainer]

And for what it's worth, I use Tobin's (DSS) 50 LCD wing with AL80s, LP85s, and HP130s. Great wing.

 

[S. starfish]

I currently dive an evolve 40 with a set of worthington HP100's. The wing size is just about perfect but I really wouldn't mind having a bit of extra lift. Once I get two deco bottles and an inflation system on there I start to sit pretty low in the water when I'm on the surface - underwater it's not an issue though. I can also float my rig (steel plate, inflation bottle) by itself, but there isn't a lot of lift capacity left over.

The evolve 60 would just be too big .Plenty of lift yes, but if it fits a set of 100's the way I think it would, you would have a hell of a time dumping all of the air.

 

[Divin'Papaw]

I currently dive an evolve 40 with a set of worthington HP100's. The wing size is just about perfect but I really wouldn't mind having a bit of extra lift. Once I get two deco bottles and an inflation system on there I start to sit pretty low in the water when I'm on the surface - underwater it's not an issue though. I can also float my rig (steel plate, inflation bottle) by itself, but there isn't a lot of lift capacity left over.

The evolve 60 would just be too big .Plenty of lift yes, but if it fits a set of 100's the way I think it would, you would have a hell of a time dumping all of the air.

That's the problem I have with the Hollis X55 cave cut wing. It's just too wide for HP100s. Something interesting I noticed about the wing is that it's called a 55, but the label on the wing says it has a lift capacity of 61 lbs. Say what? It's hand written on the label along with the wing serial #. So it's not really a 55 but instead is a 61. That further explains the problem venting all of the air when using double 100s.

And then there's the length of the corrugated hose, but we won't go there.

 

[cool_hardware52]

The diameter of the tanks used is just not a factor in wing design, or selection.

The center panel width of a doubles wing needs to be at least as wide as the center to center distance of the tanks. This should be obvious. Manifolded doubles will contact the back plate pretty much right down the centerline of each tank.

Modern manifolds are almost all 215mm or 8.46" That means the center panel of a doubles wing needs to be a but 9" wide to prevent any of the inflatable portion from being trapped between the cylinders and the back plate.

The inflatable portion of the wing will be outboard of the center panel.

While there are some variations from design to design the max width of the wing is mostly a function of the capacity of the wing.

In other words if the center panel is "fixed" at ~9" and you "need" 60 lbs of capacity, the "pontoons" on each side of the wing will have to be wider than if you "need" only 40 lbs of capacity.

Does tank diameter determine required lift capacity? NO!

Required lift capacity is a function of the weight of the back gas, and the buoyancy of the divers exposure suit.

Example #1

8 inch E8 130s, warm water, thin undies, i.e. fleece with a Dry suit that is 16 lbs positive with minimum gas in it.

Back gas = ~20 lbs + 16 (suit buoyancy) = 36 lbs. Min wing lift 38-40 lbs.

Example #2

7 inch Lp 85's, cold water, thick undies and a suit buoyancy of 30 lbs.

Back gas = ~13 lbs + 30 (suit buoyancy) = 43 lbs Min wing lift 45-50 lbs.

Tobin

 

[TSandM]

Just a comment about whether your wing needs to be able to float your rig without you in it . . . On any number of boats I've dived from, you doff gear in the water, climb into the boat, and pull your gear in behind you. Although the gear IS tethered to the boat, it's awfully nice if it stays on the surface.

 

[cool_hardware52]

Just a comment about whether your wing needs to be able to float your rig without you in it . . . On any number of boats I've dived from, you doff gear in the water, climb into the boat, and pull your gear in behind you. Although the gear IS tethered to the boat, it's awfully nice if it stays on the surface.

TSandM,

You make a good point. I will point out that WRT doubles there are very few gear combos that result in a "rig" that will be more negative than the weight of the BG + the Buoyancy of the diver's suit + ~2-3 lbs.

If the rig is the controlling factor something is usually amiss, and the diver is over weighted.

Tobin

 

[b1gcountry]

If the rig is the controlling factor something is usually amiss, and the diver is over weighted.

If the undergarments get thick enough...

With my 400g thinsulate, diving in fresh water, I only take 4lbs, which I usually stash in my undergarment pockets. Diving Steel 100s, this comes out to:
16 lbs air
8 lbs tanks, manifold, bands
4 lbs regs
10 lbs plate
2 lbs can light

So my rig is around 40 lbs negative, and it will not float with a jacked up wing, using my smaller doubles wing. The wing works perfect otherwise, it just won't float my rig without buoyant me inside it.

My wife has the same problem with her 30lbs singles wing when she is diving a steel plate and HP130 in fresh water.

Tom

 

[cool_hardware52]

If the undergarments get thick enough...

With my 400g thinsulate, diving in fresh water, I only take 4lbs, which I usually stash in my undergarment pockets. Diving Steel 100s, this comes out to:
16 lbs air
8 lbs tanks, manifold, bands
4 lbs regs
10 lbs plate
2 lbs can light

So my rig is around 40 lbs negative, and it will not float with a jacked up wing, using my smaller doubles wing. The wing works perfect otherwise, it just won't float my rig without buoyant me inside it.

Tom

Perhaps you misunderstood my previous post.

Your "rig" with empty tanks represents about 24 lbs of ballast, using your numbers. If you need an additional 4 lbs of ballast we can assume that your Drysuit is about 24 + 4 = 28 lbs positive.

I stated earlier that the minimum wing lift required is the weight of your back gas, (~16 lbs) + the buoyancy of your suit (~28 lbs.) + ~2 lbs. 16 + 28 +2 = 46 lbs.

A 46 lbs or larger wing will certainly float your ~-40 lbs rig.

In short, with 16 lbs of back gas and a suit that is ~28 lbs positive a 40 lbs wing is too small.

Tobin

 

[MonkSeal]

On any number of boats I've dived from, you doff gear in the water, climb into the boat, and pull your gear in behind you.

My experience is completely opposite - hand stages if any and climb into the boat with backgas tank(s).