Wing lift?

[tbone1004]

better question is why are you so overweighted? If you have 9lbs of suit buoyancy why do you have that much extra lead on you?

Reg 2lbs max ish, likely less
SSplate with STA/Harness/Wing/SS cam bands is right around 10lbs total. Harness isn't 2lbs, in the water, closer to 1, and is offset by the slight buoyancy of the wing and inflator, 10lbs is pretty accurate since the plates are actually about 5.7lbs. Neither here nor there
AL80 is 1lb negative when full

So you're at call it 14lbs negative for just the rig. so S25 is plenty for that
You claim 10lbs and 18lbs for the wetsuit, so
10-14=-4. 4+14=18lbs
18-14=4, throw 4lbs of lead on there, 6 if you really want to. 6+14=20.
Now, I will see you are likely grossly overweighted, you shouldn't need that much weight with a SS plate, STA, and likely stainless cam bands, I would HIGHLY recommend getting a new weight check done because that is too much unless you have a LOT of natural insulation....

Wetsuits are generally 2-3lbs per mm, so 9lbs for 3mm worst case and that drops to about 3lbs of buoyancy at 60 or so feet, 5mm is 15 down to call it 5.
25 isn't enough with the 5mm suit if you're doing dives to 20m or more regularly, and you'd want to go to 30-35lbs. The Hog 32lb wing comes out of the same factory as the Hollis wings and will serve you much better and likely cheaper, not sure about international dealers, but Dive Right in Scuba and Dive Gear Express both ship internationally

 

[Subcooled]

My question is, why would anyone ever need a wing with 40 pounds of lift? If you're weighted to be roughly negative 10 pounds buoyant, it seems like 40 pounds of lift from a wing would be overkill?

I am diving in near freezing waters. I have a drysuit and thick undergarments. I need a lot of air (or argon) inside the suit to stay warm. The suit requires 16 lbs of lead weights to sink (with empty tanks). In addition, I am carrying almost 14 pounds of gasses. That is a total of 30 pounds. If my drysuit would fail on the surface, I would need 30 pounds of lift. And then I have some other stuff.

 

[GrumpyOldGuy]

Short answer: If you dive with integrated weights you generally need a larger amount of lift due to the desire to float the rig separate from you. Diving thick wet suite or d/s, this can require 40 lbs lift (or more in extreme cases). Put the same weights on a belt or harness and 26-30 becomes more than enough for typical rec divers.

 

[danvolker]

I am diving in near freezing waters. I have a drysuit and thick undergarments. I need a lot of air (or argon) inside the suit to stay warm. The suit requires 16 lbs of lead weights to sink (with empty tanks). In addition, I am carrying almost 14 pounds of gasses. That is a total of 30 pounds. If my drysuit would fail on the surface, I would need 30 pounds of lift. And then I have some other stuff.

.
I get the issue with drysuit in very cold water..maybe even over bottom that is far too deep for you to purposely reach it

On the other hand, I think you need to be able to swim upward, no matter what--and be able to make it to the surface by swimming. The BC/wing is NOT supposed to be the elevator to make this "ride", to be zero work....I think the Wing needs to be able to get you neutral at the bottom....If my TLS 350 drysuit was to flood completely near the surface, or at depth, the real issue is "how hard will it be for me to swim to the surface and remain there, until the boat picks me up..

Certainly I can lift 10 or 15 pounds for a long time, if I need to, by finning. Clearly I have dive buddies nearby, that are also redundant buoyancy opportunities that follow me around on all dives....Certainly I can carry an SMB in a backplate pouch, completely out of drag with swimming or currents, and in an emergency, this could double as the "raft" for surface lift that may be desired by some

The idea to me, is to be as slick in the water as possible, on the 99.999% of my dives where there will be no significant flooding of the drysuit, or no failure of my wing.....As I have enjoyed tens of thousands of dives since being certified in 1972, I think I can speak to the statistical low liklihood for an individual....In all this diving, I have only had one BC/wing failure, with an old AtPac lent to me by Frank Hammett...and I have never had a dry suit flood that caused any difficulty at all in swimming to the surface....On the other-hand, I am passionate about my enjoyment of diving with near zero drag suits( in tropical waters), which ELIMINATES pretty much all drysuits....If I have to dive in water colder than 50 degrees, or deeper than 200 feet, I will use a dry suit, and be "happy about it"

 

[Manta Man]

Ok, hmmm!!?? Sorry still confused. Got the first part re- the rig - no probs. The rest??? Puzzled ..... Let me put it another way. I am a pretty slim guy about 70kg/140ibs. I dive mainly with two suits a 3mm and/or a 5mm, and yes often beyond the 20m mark, but not beyond 30m of sea water. Using a regular BCD, with the former I use, for myself, 4Kg/8Ibs & the latter 7Kg/14Ibs for myself. I also have to carry 2kg/4Ibs extra lead for underweighted clients, so that's the 3mm@6kg/12Ibs or 5mm@9kg/18Ibs.

So, with that in mind, IYO, will the S25 have the sufficient amount of lift capacity, for me, for both suits with an almost full tank at 30m/20m and keep me buoyant on the surface before/after the dive? And how do you calculate this?

Cheers

 

[1bubbleoff]

http://www.scubaboard.com/forums/bu...ems/158370-ultimate-wing-lift-calculator.html

 

[Manta Man]

Thx, but the link doesn't work anymore. I download it on my MAC sometime ago but it doesn't seem to work, I have M/S Excel for MAC, not numbers. What does it say?

 

[runsongas]

did you try the attached xls from page 11 of that thread? post 110

 

[Manta Man]

Ok got it & downloaded it. I completed the doc for a 25Ibs lift of wing, just do quite understand the results????