Wing size/lift calculation questions.

[Peter_C]

If it came down to it and you had to ditch a belt completely because your suit was flooded and your wing was junk you would not rocket to the surface because there would be no air cavity to speak of that would be able to expand enough to cause a rapid ascent. Some trapped air up high in the suit maybe or a high spot in a cut wing. But at that point I think just getting to the surface would be my primary goal. Where we dive a complete drysuit flood in 48 degree water means you would have only a few minutes to get something done or else paralysis and hypothermia will get you in short order.

I really have no idea how much air a Thinsulate undergarment is going to hold, and that is the unkown. Buoyancy could change in a few seconds or take minutes as the suit fills with frigid ocean water. I know it is going to have more thermal protection than fleece when flooded. Those that have completely flooded just seem to say they got very cold, but not hyperthermic. Of course getting out of the water with a suit full of water was a royal pain, with one person crawling out...barely. Might have to cut a large hole in the foot to get back onboard my boat LOL I have had minor floods and completed the dive shivering, but much less than I would have in a wetsuit. Came out with water up to my calf's.

For me changing from an original Oxycheq Signature 30lb wing to a 40lb Mach V was an upgrade in many different ways. No longer having a kit that sinks is a nice advantage and the main reason I upgraded wings. The Mach V is an awesome wing that I am very happy with. So far no failures with any of my wings, just maintenance on the o-rings. On a pre-dive check I did find a damaged inflator hose, on my doubles wing, and promptly replaced it. I much prefer to find failures upon topside inspections before going diving.

My thought is a diver should be pretty much neutral underwater without their kit on their person. This allows an underwater doff and don should the need arise. Weight integrated sucks! I know I owned one for about 20 dives before being lead down an expensive path that was futile to resist. At least I can still use the regs I bought, but most everything else got sold.

Wetsuits? I tried two at once and still froze my butt off. At the beginning of the dive I had to put my feet in the air and swim down in order to descend, then I was fine for the rest of the dive. Probably weight correctly. Now in a drysuit I run about 2lbs heavy for comfort. Lets me loft my drysuit for more warmth at the end of the dive when I need it the most. I dive with 20lbs on my belt and have dove with 16lbs, but it was very uncomfortable and I was always on the verge of corking.

 

[Eric Sedletzky]

I really have no idea how much air a Thinsulate undergarment is going to hold, and that is the unkown. Buoyancy could change in a few seconds or take minutes as the suit fills with frigid ocean water. I know it is going to have more thermal protection than fleece when flooded. Those that have completely flooded just seem to say they got very cold, but not hyperthermic. Of course getting out of the water with a suit full of water was a royal pain, with one person crawling out...barely. Might have to cut a large hole in the foot to get back onboard my boat LOL I have had minor floods and completed the dive shivering, but much less than I would have in a wetsuit. Came out with water up to my calf's.

For me changing from an original Oxycheq Signature 30lb wing to a 40lb Mach V was an upgrade in many different ways. No longer having a kit that sinks is a nice advantage and the main reason I upgraded wings. The Mach V is an awesome wing that I am very happy with. So far no failures with any of my wings, just maintenance on the o-rings. On a pre-dive check I did find a damaged inflator hose, on my doubles wing, and promptly replaced it. I much prefer to find failures upon topside inspections before going diving.

My thought is a diver should be pretty much neutral underwater without their kit on their person. This allows an underwater doff and don should the need arise. Weight integrated sucks! I know I owned one for about 20 dives before being lead down an expensive path that was futile to resist. At least I can still use the regs I bought, but most everything else got sold.

Wetsuits? I tried two at once and still froze my butt off. At the beginning of the dive I had to put my feet in the air and swim down in order to descend, then I was fine for the rest of the dive. Probably weight correctly. Now in a drysuit I run about 2lbs heavy for comfort. Lets me loft my drysuit for more warmth at the end of the dive when I need it the most. I dive with 20lbs on my belt and have dove with 16lbs, but it was very uncomfortable and I was always on the verge of corking.

I talked to an urchin diver up at Albion last year he was telling me he pulls on three 7mm wetsuits to go urchin diving :shocked2:

Whenever I mention 15 foot stop with no air in wing I am speaking for wetsuit diving since that is what I do. Drysuits need a little more weight because it is nice to have some loft throughout the dive. I remember this from my drysuit days.

 

[Eric Sedletzky]

I'd caution that promoting weighting or BC requirements based on using wetsuits made from uncommonly encountered high density materials is *not* a service to the SB readership. Far too many *extra super duper mega stretch* suit are sold today, and these are pretty ease to compress.

Tobin

Hey man, I've tried for many years to try and promote local (USA) custom suitmakers on this board and others.
It's not my problem if people can't seem to figure out that there is a whole other wetsuit world out there besides the the kitchen sponge they sell you at your local LDS.
It's not like I'm keeping it a secret.

Yes, some big industry dive gear IMO is heading in a downward spiral to keep costs low and profits high.
It's up to the individual to find the info they need to bypass the mainstream.

Me, I went to the docks and talked to an urchin diver about what they use. The answer was M&B custom rubatex wetsuits, it's what they all used at the time.
If I would have walked into my LDS they would have had me try on the latest kitchen sponge and claimed it was the best thing in wetsuit history.

Here ya go you SB'ers who want to know about commercial material wetsuits.
Don't ever say I didn't give you 'nothin.

M&B Wetsuits
(562) 422-3493

 

[cool_hardware52]

Hey man, I've tried for many years to try and promote local (USA) custom suitmakers on this board and others.
It's not my problem if people can't seem to figure out that there is a whole other wetsuit world out there besides the the kitchen sponge they sell you at your local LDS.
It's not like I'm keeping it a secret.

None of that changes the fact that most wetsuits sold today aren't high density, and will easily compress.

I've always been an advocate for using the smallest wing that safely meets the divers needs, but I'm also careful to consider the range of readership here at SB.

Tobin

 

[Eric Sedletzky]

None of that changes the fact that most wetsuits sold today (in LDS's) aren't high density, and will easily compress.

There I fixed it for ya.

Actually as far as my constant ranting on this board about the superiority of custom suits, yes it has changed a lot. There are several people that have benefited from my posts about custom suits and decided to try one.
Scubaboard is not an LDS. On scubaboard people learn about things like BP/W's, custom wetsuits, DIR, vintage, etc. You will not learn a thing about any of this at an LDS.

I've always been an advocate for using the smallest wing that safely meets the divers needs, but I'm also careful to consider the range of readership here at SB.

I give SB readers a little more credit than that. You have to realize that most of them have been pre programed by their LDS's and the gear and training they buy. Most that are hungry for something further will actively seek it out and ask questions. Part of that hunger is finding and joining SB. Most divers in the world have never even heard of SB and could care less, so the ones here at least have a huge head start just by the fact that they're here..

As far as spongy wetsuits, yes they lose buoyancy much quicker that the ones I use, but still doesn't mean that all or a good portion of balast has to be put on the rig.
Even with how much they crush down, a wing just large enough to cover compression can be used just fine regardless if it can float the rig on the surface or not.
To float the rig; a handy convenience yes, absolutely necessary no.

Using a spongy suit to dive with no BC? not very well with a 7 mil. but a thin one yes.
I was merely illustrating the fact that a rig does not have to float on the surface if it's part of the diver and the diver floats.
One step further would be having a micro wing on the same rig that is only used at depth for compensation which if the diver is weighted correctly is only a very small amount of air.

 

[cool_hardware52]

There I fixed it for ya.

Actually as far as my constant ranting on this board about the superiority of custom suits, yes it has changed a lot. There are several people that have benefited from my posts about custom suits and decided to try one.
Scubaboard is not an LDS. On scubaboard people learn about things like BP/W's, custom wetsuits, DIR, vintage, etc. You will not learn a thing about any of this at an LDS.


I give SB readers a little more credit than that. You have to realize that most of them have been pre programed by their LDS's and the gear and training they buy. Most that are hungry for something further will actively seek it out and ask questions. Part of that hunger is finding and joining SB. Most divers in the world have never even heard of SB and could care less, so the ones here at least have a huge head start just by the fact that they're here..

As far as spongy wetsuits, yes they lose buoyancy much quicker that the ones I use, but still doesn't mean that all or a good portion of balast has to be put on the rig.
Even with how much they crush down, a wing just large enough to cover compression can be used just fine regardless if it can float the rig on the surface or not.
To float the rig; a handy convenience yes, absolutely necessary no.

Using a spongy suit to dive with no BC? not very well with a 7 mil. but a thin one yes.
I was merely illustrating the fact that a rig does not have to float on the surface if it's part of the diver and the diver floats.
One step further would be having a micro wing on the same rig that is only used at depth for compensation which if the diver is weighted correctly is only a very small amount of air.

Simple rules with few qualifiers are the most easily followed.

If a diver can provide me with *real* numbers for the buoyancy of their suit, then they will end up with a pretty small wing, usually much smaller than what they were "told" they needed.

If they avoid hanging 100% of their ballast on their rig this same modestly sized wing will also float their rig.

Tobin

 

[Sat Diver]

Totally agree with you on the wetsuit issue, but with regards to being positive on the surface with a full tank, I see that as being a big problem on ascent. You would be severely underweighted once you use your gas.
This would create a safety issue for deco or safety stops, or potentially even controlling your ascent.

The reason I brought up the topic of an overweighted diver as a side note in this discussion was illustrate the danger of overweighting plus the humongous wings used these days that covers for overweighted divers at the surface.

There was a diver who died 50 feet from shore in San Diego several years back because he was overweighted and his inflator came undone at the wing which allowed all his air to vent and he dropped like a rock. Two divers were coming back in after a shore dive and there was a little beach break happening. Diver A (the one who made it) and diver B (the one who died) were just outside the break zone setting up to get through the break and get to shore.
Many times during those types of exits it becomes every man for himself because of the intensity which can be very high and all your energy gets used just trying to get yourself in and keep things under control. Both divers said OK see you at the beach and they started in. Somewhere along the line diver B's inflator broke off and all his air vented and he went straight down. Apparently he did not have his reg in his mouth or lost it and could not find one to breath off in the chaos. He must have panicked and was unable to ditch his weights or his rig. The result was that he drowned 50 feet from shore in 10 feet of water. They found later that the diver was grossly overweighted and if he had been properly weighted he would been able to stay on the surface even with no air in his BC and would not have sunk like a rock to his demise. I blame the huge wings that can lift a bus for helping to mask the problems of overweighting.
In my understanding of what I have learned over the last 13 years is that a diver should be able to float on the surface with a full tank with no air in the air cell. I have found that with this system a diver may need to descend head first and kick down for the first few feet but then after a certain amount of suit compression there will be a neutral zone then upon further descent a little air can be introduced into the air cell to achieve neutral buoyancy.
The system of loading up a diver with tons of weight then relying on the wing to elevator dive to me is not only nuts, it's cumbersome, annoying, and unsafe.

Drysuit only divers that like to load up your rigs with all kinds of non ditchable weight, I have a question.
What if you were to have a catastrophic failure of your drysuit (total flood) and your inflator came undone so you have no redundant buoyancy whatsoever. Do you have enough of your weight on your belt to lighten up enough to swim you and your rig up?

Don't poo poo wetsuit divers too much we're smarter than you think.
A wetsuit IS a form of redundant buoyancy. It doesn't flood and fail even if ripped wide open or if a zipper comes completely undone. You might get cold but the suit material is still there and will still provide floatation. It might work a little differently than a drysuit but it's reliable every time.

 

[Eric Sedletzky]

Totally agree with you on the wetsuit issue, but with regards to being positive on the surface with a full tank, I see that as being a big problem on ascent. You would be severely underweighted once you use your gas.
This would create a safety issue for deco or safety stops, or potentially even controlling your ascent.

Where I dive the water is very cold so we use thick wetsuits. I use my wetsuit at the surface for floatation. It just so happens that it works to keep me on the surface with a full tank.
My weighting has been carefully calculated so that at the end of the dive with a near empty tank I can hold a stop at 15 feet. Above that I slowly rise. With no air cell it is difficult to cork to the top, wetsuits slowly expand so becoming a missle isn't an issue.
I don't put myself into deco and my dives tend to be short and shallow so many times I don't even need to do a safety stop if I don't want to. Or many times they are integrated safety stops meaning I follow the contour of the ocean floor out and back on a shore dive.
I find wingless diving perfect for these profiles.