Buoyancy question regarding which wing I should get.

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Seefourdc

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I'm going to support my LDS and out of the brands they sell OMS backplate/wing are the best option. The options are either the 32 lb. or 45 lb. wing and I only plan on diving singles on this setup. I currently own a 3.5 mm wetsuit and I'm sure the 32 will cover that if I'm neutrally weighted but here is my question. Lets say I wanted to extend my dive season and buy a 7 mm semi-dry, at 6'2.5 240 (mostly muscle, wear an XLT in my 3) do you think there is any chance I would need a bigger wing to wear that suit? I appreciate any input!
 
Most people don't need more than a 30lb wing for single tank diving, but do the math just to be sure.


For the most part your suit will provide some additional buoyancy to help you. You'd be hard pressed to zero out it's positive bouyancy char. by descending to depth. At a single tank recreational level, you will always have some positive buoyancy from your suit.
If you were wearing a drysuit then you would have to plan for a complete loss of positive buoyancy in that via a drysuit flood/undergarments soaked and saturated (loss of buoyancy in the undergarments); then plan your lift capacity accordingly.

The real question to ask yourself if how much weight will you be using with the 7mm suit? Add that weight plus your tank (most negative tank you'll be using to make it simple), plus your gear (camera, accessories etc) and you have your total negative ballast. Ignore that your suit gives positive buoyancy even at your depth range, and you'll have a pretty conservative number for what lift capacity you'll want in a wing. Even better, on the surface you'll be given extra "lift" by your non-compressed suit, meaning you won't have to inflate your wing fully and contend with a big pillow to counterbalance against.

As an example, I had a stock BC that gave me 23lbs of lift capacity. At times I wore 22lbs with a Al 50, which gets about -2.4lbs when full. So I was technically overloading the lift capacity of my BC, but with my 7mm 2-piece wetsuit, I never had to inflate it past 50%, unless I wanted to be real high up out of the water.
However, if I had placed all my lead in the BC, it would have sunk without me attached to it, but that's what a weightbelt is for.
 
32 should be plenty with a single cylinder.

The 45 pound wings are usually hybrid single/double wings and are pretty sloppy as singles.
 
I have a question...
I was playing victim in a coldwater rescue class using my Halcyon 40# wing with an AL backplate and 6# Sta weight, steel 100 full, dry suit with 16# of lead on my belt. This is a balanced rig and works great. On the surface, I have plenty of lift.

BUT

when I was rescued as an unresponsive diver, the drill calls for the victim (me) to have all his gear stripped off by the rescuer. A handler takes the gear and floats it on the rescued persons gear.

Problem 1. Never play victim in a wing (duh.) because the best way to get a victim out of a wing is to cut them out. I have slider things for my straps and they didn't resort to cutting me webbing :)

Problem 2. 16# lead plus 3# AL plate plust 6# STA weight, plust 10# full tank plus 4# regulator... my wing barely supports all my gear on the surface without the help of my dry suit.

So, here's my question: When diving a wing in a balanced rig, is it still best practice to have sufficient lift in your wing ALONE to support all your gear?
 
I have a question...
I was playing victim in a coldwater rescue class using my Halcyon 40# wing with an AL backplate and 6# Sta weight, steel 100 full, dry suit with 16# of lead on my belt. This is a balanced rig and works great. On the surface, I have plenty of lift.

BUT

when I was rescued as an unresponsive diver, the drill calls for the victim (me) to have all his gear stripped off by the rescuer. A handler takes the gear and floats it on the rescued persons gear.

Problem 1. Never play victim in a wing (duh.) because the best way to get a victim out of a wing is to cut them out. I have slider things for my straps and they didn't resort to cutting me webbing :)

Problem 2. 16# lead plus 3# AL plate plust 6# STA weight, plust 10# full tank plus 4# regulator... my wing barely supports all my gear on the surface without the help of my dry suit.

So, here's my question: When diving a wing in a balanced rig, is it still best practice to have sufficient lift in your wing ALONE to support all your gear?

If you put all your lead attached to your BC and it sinks without you in it, then you're not really diving a balanced rig. Suppose you have to ditch your Bp/ underwater to clear an entanglement? You need some weight on your body via a belt or harness.
Your BC should always be able to float on the surface without you attached to it. Likewise, you should be able to float without your BC attached, on the surface.

Secondly with rescuing a person from a hog harness in a class setting. Have the rescuer raise your arms up, then slide you down one way and the BC up the opposite way. Works great if you've set your straps right (which should already be loose enough for you to easily slide off your shoulders), especially if they don't over inflate your wing so you're lifted out of the water.

As a bit more of a tidbit, if you're diving a Halcyon system, which I assume:
Bp is 1.8lbs
STA 1lbs
weighted insert 6lbs
SS Camstraps: is either 1-2lbs together. I can't remember exactly for that one.
 
I have a question...
I was playing victim in a coldwater rescue class using my Halcyon 40# wing with an AL backplate and 6# Sta weight, steel 100 full, dry suit with 16# of lead on my belt. This is a balanced rig and works great. On the surface, I have plenty of lift.

BUT

when I was rescued as an unresponsive diver, the drill calls for the victim (me) to have all his gear stripped off by the rescuer. A handler takes the gear and floats it on the rescued persons gear.

Problem 1. Never play victim in a wing (duh.) because the best way to get a victim out of a wing is to cut them out. I have slider things for my straps and they didn't resort to cutting me webbing :)

Problem 2. 16# lead plus 3# AL plate plust 6# STA weight, plust 10# full tank plus 4# regulator... my wing barely supports all my gear on the surface without the help of my dry suit.

So, here's my question: When diving a wing in a balanced rig, is it still best practice to have sufficient lift in your wing ALONE to support all your gear?

Yes. It is.
 
Thanks G1138 - Yes, you are right about the details of the H system. And Yes, you are correct about raising the hands and slipping out of the wing.

Point of clarification here- the 16# of ditch-able weight is on a belt of course, not on the plate. The Wing and non-ditchable weight floats on the surface just fine, and the belt and I, in my dry suit, float on the surface just fine. Lots of extra lift in that scenario. If I ditch my weight belt onto the floating Wing, it still floats, but just barely.

In my drysuit, I absolutely can swim the rig up and hold a 15' safety stop without any air in the wing. As indicated, the wing can float all my gear, including ditched weight belt, on the surface with a full steel 100, independent of me, but just barely. This rig has only the weight and lift needed and no more, and it includes the lift in my dry suit to meet that standard. In short, I think it's balanced but I haven't taken DIR fundies. Looking forward to that.

The question I'm working through is that if I where add a heavy light, for example. The Wing would support everything attached to the wing, and the light. But If I threw the weight belt onto the wing, it would sink. In that case, is the wing too small? I don't think so, because the only case where you don't have enough lift at the surface is in a training event. In all other cases, the diver would just ditch the ditch-able weight- right?

I know its a fine point, but that's what SCUBAboard discussions are best at :)

---------- Post added February 2nd, 2013 at 11:44 PM ----------

GCarter beat me to it.
Thanks!
 

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