Optimal lift capacity of a wing with a single tank in warm saltwater

[WKenny]

For diving in warm saltwater, with a 3 mm shorty wetsuit, and 17 pounds of weight, what is the optimal lift capacity of a wing for a single tank considering safety at the surface and streamlining for minimal resistance underwater? Thank you for taking the time to respond.

Bill Kenny

 

[Cio]

If your neutral, you would only need a little over 6# of lift. If you want to be streamlined get an 18# wing, it is plenty for single tank in a 3mm.

The real question here is why on earth are you using 17# of weight ion a 3mm shorty? You need to sort that out.

 

[WKenny]

If your neutral, you would only need a little over 6# of lift. If you want to be streamlined get an 18# wing, it is plenty for single tank in a 3mm.

The real question here is why on earth are you using 17# of weight ion a 3mm shorty? You need to sort that out.

Thank you for your response. I appreciate you taking the time to write it. The reason I'm using 17 lbs of weight is because I need that amount of weight to descend from the surface in saltwater with a 3 mm shorty wetsuit without struggling to get down. I've dived in Cozumel a number of times and consistently I've found that is the weight I need. Do you think that weight is excessive in those conditions? What is your experience in those conditions? I'm about to buy a new wing and I'd like to get the most streamlined one I can to avoid drag when swimming underwater. I'd love to buy a wing with just 18 lbs of lift, but I'm afraid that may not be sufficient for buoyancy at the surface. Do you have any further thoughts or ideas?

 

[Lorenzoid]

Do you think that weight is excessive in those conditions?

Yes, it is excessive. Something is amiss here, and I'm confident others will chime in to help you figure out the root of it. One thing you could think about is whether you are perpetually finning before you attempt to descend--like treading water--without thinking about it. Concentrate on keeping the feet still, then deflate the wing fully, maybe exhale a bit, and down you should go.

With a backplate and wing, and diving an Al 80 in a 3 mm shorty, you should need less than 10 lbs. I use a steel backplate, and with a 3mm FULL suit I add no more than about 4 lbs. of lead. If I were to use an aluminum or carbon fiber plate, I would need a few pounds more.

 

[Cio]

I'm not huge, salt water, 3 mm shorty alu 80, like 5-6# is fine I just use a SS backplate, no lead.

If you do really require the 17#, you and your rig are very buoyant. You could still use a small wing, the wing is only really compensating for the air in the tank, 6# and some suit compression (3mm shorty, 2#.

 

[WKenny]

Yes, it is excessive. Something is amiss here, and I'm confident others will chime in to help you figure out the root of it. One thing you could think about is whether you are perpetually finning before you attempt to descend--like treading water--without thinking about it. Concentrate on keeping the feet still, then deflate the wing fully, maybe exhale a bit, and down you should go.

With a backplate and wing, and diving an Al 80 in a 3 mm shorty, you should need less than 10 lbs. I use a steel backplate, and with a 3mm FULL suit I add no more than about 4 lbs. of lead. If I were to use an aluminum or carbon fiber plate, I would need a few pounds more.

Ok, I'll reevaluate the weight. Thank you for your advice

 

[James79]

Not mentioned yet are 2 things:

1) What type of BCD are you using with the 17lbs? BCD's with padding will need more lead to initially sink them due to trapped air in the padding, in addition to plain old material densities.

2) In a perfect, properly weighted, world you only need to compensate for two things with wing lift; weight of air that will be consumed (about 6 lb for singles), and buoyancy loss for wetsuit compression at depth (minimal with a 3mm shorty). In the imperfect reality, you want a little headroom for imperfect weighting, a little headroom for assisting a buddy, and you should ensure your rig can support itself. If you use a steel tank and put your 17 lb lead on integrated pockets, then that 18 lb wing won't cut it if you have to remove the rig at the surface. My weighting is pretty close, I dive steel tanks, but I use a weight belt for the lead I do wear, and my 14lb wing is just fine.... but my window for "close enough" weighting is pretty narrow.

If able, I'd recommend nailing down weighting with a BPW (yours if you have one, or borrowed if this is all in prep to get one) and swim suit in a pool with a 500psi tank. Adjust lead until you can have the wing empty and a medium breathe still lets you hover or be flat at the bottom of the pool. That will give you a good baseline and then adjust for exposure protection.

One final thought... I make my own wings. My daily diver is a 14 lb nearly non existent one. My usual "loaner" is closer to 25 lb, and feels the same in the water. Any of narrower style 18-30 lb donut wings will feel stupidly clean in the water compared to a jacket BC.

Respectfully,

James

 

[rongoodman]

Ok, I'll reevaluate the weight. Thank you for your advice

How much gas do you currently have in your wing at your safety stop? If it's more than a fistful or so, you've got too much weight on. (Go a little head down and reach around behind you, you can easily feel how much gas is there.)

 

[inquis]

Delete

 

[TheRealScubaSteve]

Yes, it is excessive. Something is amiss here, and I'm confident others will chime in to help you figure out the root of it. One thing you could think about is whether you are perpetually finning before you attempt to descend--like treading water--without thinking about it. Concentrate on keeping the feet still, then deflate the wing fully, maybe exhale a bit, and down you should go.

With a backplate and wing, and diving an Al 80 in a 3 mm shorty, you should need less than 10 lbs. I use a steel backplate, and with a 3mm FULL suit I add no more than about 4 lbs. of lead. If I were to use an aluminum or carbon fiber plate, I would need a few pounds more.

Ok, I'll reevaluate the weight. Thank you for your advice

I needed 12 pounds in a 2.5 mm full suit and BCD on my first vacation dive after certification. It was excessive, as the divemaster got me down to 8 pounds or so with some guidance. I was finning at the surface without realizing it and was breathing too rapidly. Slow exhales help a great deal and I made a concerted effort to consciously monitor my breathing.

Did the same trip a couple years later with 50 or so additional dives under my belt and I needed only 6 pounds with a 5 mil suit and same BCD.

This was an epiphany moment for my diving when everything just clicked. My weight, trim, air consumption, and overall control had never been so dialed in. It made diving much more enjoyable and really demonstrated the importance of getting dialed in. It was one of those things that is difficult to describe exactly, but "you'll just know."