Too much lift?

[stuartv]

Is it unrealistic to think that one setup could work well for recreational single tank diving in both warm and cold water?

No. You can definitely get a cold water wing that will also work just fine for warm water. It will work better than any of the integrated BCs with the gigantic bladders that are sized to still work for the average vacation diver that is severely overweighted.

What you have picked up on is the purists who translate "a smaller wing will work better" into "you NEED a smaller wing" (for warm water).

 

[REVAN]

I'm not so sure a 17# wing is a good idea for cold water diving.

If you are properly weighted and diving a 100, you'll start the dive around 8# negative. If you're wearing a 7mm wetsuit and dive past 100' (just for example), I think suit compression could easily lose you 10 # of buoyancy. At which point, a 17# wing would not even be able to hold you up off the bottom.

Diving an AL80 is only 2# better. If your suit loses 12 # of buoyancy, you're in exactly the same situation.

It depends on the diver and how they are planning to dive. If you are fully dependent on the BC for buoyancy control and want to dive big steel tanks, then the 17 may be cutting it too close for your comfort level.

If you employ some structured breathing techniques (a highly desired skill for an OC scuba diver to have), you'll gain extra buoyancy control in addition to what the BC provides. How much extra, will depend on the individual, but I think most people can count on at least an easy 4 pounds. For me, I get an easy 6 pounds of additional control from employing structured breathing techniques. So for me, a 17 pound wing would actually give me no less than 23 pounds of active buoyancy control during the dive. That's more than enough for me dive my 7mm wetsuit at recreational depths with a steel 100, or even a 120. Also, I rarely dive anything bigger than an 80 these days anyway. Even when my dive buddy is on a 100, I still have more air than I need in an 80 by anywhere from 500 to 700 psi over the safety margin, so I don't really have a reason to carry anything bigger. Part of that advantage is from employing structured breathing and part is from paying attention to drag reduction and and swimming hydrodynamics.

The best path and gear plan for an individual will depend on their physical size, abilities, priorities and mission goals. If I was in the OP's situation, I'd opt for the 17. But, that's for me, and how I would use the equipment. It may not be the best plan for someone else and how they would want to use it.

 

[cipherbreak]

I have a 17# and a 30#. I could dive either in cold or warm water but some scenarios require compromises I wouldn't be comfortable making.

If you are diving a thick wetsuit, you will need to account for the substantial loss in buoyancy. If you are driving dry, you might want to account for a situation when you start dry and end very wet. Either way, the 17# might not be sufficient/adequate, especially if diving heavy tanks.

What is absolutely true is that the 17# packs much smaller and is just nicer for a traveling rig. The 30# is more forgiving of "unsound" configurations.

I can't say for sure without specifics about your configuration, but I'd get a 30# wing first. You can use it on both cold and warm water with only minor inconvenience, if any. If you have the resources and the interest in the future, get a smaller wing for warm weather/travel at that time.

 

[cool_hardware52]

Is it unrealistic to think that one setup could work well for recreational single tank diving in both warm and cold water?

How about one exposure suit for use worldwide? Just get a 7mm farmer john. Sure it's a bit much for the Tropics..........



Tobin

 

[halocline]

I've experienced that. How much does a bungied setup on the bladder help?

Actually it hurts by trapping air in little pockets created by the bungee. Bungeed wings are one of the dumber ideas put forth by an industry known for its dumb ideas.

I suggest you first get the wing that is ideal for most of your diving, apparently warm water, and then get cold water gear when you get really interested in local diving. I doubt you'll be doing much in New England without a dry suit, and after buying one of those, spending a few hundred on a bigger wing will be peanuts.

The big issue with diving a larger-than-necessary wing is the venting. Small, low profile wings vent very efficiently and somewhat disappear in the water. That makes diving all the more fun.

I use a 17lb oxycheq wing for single tanks and a dive rite rec wing for doubles. The rec wing is sold as a hybrid single-doubles wing, and IMO it's too big for my AL80 doubles! I can't imagine using it on a single tank.

 

[2airishuman]

I'm not so sure a 17# wing is a good idea for cold water diving.

If you are properly weighted and diving a 100, you'll start the dive around 8# negative. If you're wearing a 7mm wetsuit and dive past 100' (just for example), I think suit compression could easily lose you 10 # of buoyancy. At which point, a 17# wing would not even be able to hold you up off the bottom.

To be clear, I never said it was a good idea.

With any wetsuit, almost half the buoyancy change that takes place between 0 and 130 feet will occur in the top 15 feet. If the weighting is chosen to be neutral at the safety stop with 500 PSI left and an empty BC, then the 17# swing should be just enough. That doesn't leave any reserve buoyancy. Whether reserve buoyancy is necessary from a safety perspective depends on the diver and the dive. I did a cold water dive yesterday in a lake with a maximum charted depth of 20'. Any BC would have been fine. It also would have been suitable for a gradually sloping bottom leading down to the maximum planned depth for the dive. For a boat dive on a wall, it would not be suitable.

I use a 17lb oxycheq wing for single tanks and a dive rite rec wing for doubles. The rec wing is sold as a hybrid single-doubles wing, and IMO it's too big for my AL80 doubles! I can't imagine using it on a single tank.

A true 30# singles wing isn't a big wing and is much smaller than any of the lightweight doubles wings or hybrid wings, because the shape is different (narrower). A true singles wing will not have room to inflate with doubles, because it will be almost completely trapped between the cylinders and the backplate.

 

[cool_hardware52]

If you are properly weighted and diving a 100, you'll start the dive around 8# negative.If you're wearing a 7mm wetsuit and dive past 100' (just for example),

If I'm diving in a 7mm suit with a normal sized single tank I sure won't be 8 lbs negative. Ideally I'll be about neutral. A 7mm suit will easily lose 6-7 lbs of buoyancy from the surface (1ATA) to 15 ft (~1.5 ATA) That reduction in suit buoyancy will allow me to hold a shallow stop with an empty tank.

What benefit is there in having 6-8lb of gas in your wing at your shallow stop?

Being neutral at the surface as described above reduces the impacts of any buoyancy device failure or panic. I've started many dives with smaller tanks and the old "1/4" suits where I had to swim down the first ~10 feet.

I still want to size my wing to be able to compensate for the maximum possible change in buoyancy of my suit. The typical single piece 7m suit will be in the high teens to low 20's and a farmer john 7 mm can approach 30 lbs on a bigger diver.

Tobin

 

[REVAN]

If I'm diving in a 7mm suit with a normal sized single tank I sure won't be 8 lbs negative. Ideally I'll be about neutral. A 7mm suit will easily lose 6-7 lbs of buoyancy from the surface (1ATA) to 15 ft (~1.5 ATA) That reduction in suit buoyancy will allow me to hold a shallow stop with an empty tank.

What benefit is there in having 6-8lb of gas in your wing at your shallow stop?

Being neutral at the surface as described above reduces the impacts of any buoyancy device failure or panic. I've started many dives with smaller tanks and the old "1/4" suits where I had to swim down the first ~10 feet.

I still want to size my wing to be able to compensate for the maximum possible change in buoyancy of my suit. The typical single piece 7m suit will be in the high teens to low 20's and a farmer john 7 mm can approach 30 lbs on a bigger diver.

Tobin

Agree. I will always be positive at the surface with a thick wetsuit. I give an exhale and will swim down to descend from the surface, reaching negative buoyancy usually below 4 meters depth. I aim for neutral at my planned safety stop with an empty wing. If I have air in the bladder at the end of the dive, I consider that an error and try to correct my weights so that the situation is not repeated on the next dive.

Also a 100 won't lose 8 pounds during the dive. Six pounds is a more realistic figure for what you will actually experience. The max is 7.4 pounds if the tank is completely drained to atmospheric pressure, and if that happens you'll want to be on the buoyant side of neutral anyway.

BC instability and drag are booth valid reasons to use the smallest possible BC wing that you can get by with in my opinion. My advice is to figure out what the smallest functional BC is for your situation and start with that. I think this will likely maximize your diving experience as your skills improve over time and may even make you a better diver overall.

 

[The Chairman]

Is it unrealistic to think that one setup could work well for recreational single tank diving in both warm and cold water?

It's not unrealistic. It all depends on how your wing is controlled. Tacos might be tasty, but they're lousy in a wing! I dive the 44 pound express tech and it's great. I rarely have much air in it and it never, ever tacos.

If you're diving with lots of weights, you need ditchable weights, redundant buoyancy and it's better to have both. If you have a 17# wing and your dry suit floods, you had better have ditchable weights. Best practice is to have truly redundant buoyancy. Either your wing or your dry suit should be able to get your butt to the surface. Having ditchable weights is also a good thing.

I don't get the need to have the smallest bladder that won't provide full redundancy. It's stupid and a fool's errand in my mind.

 

[decompression]

Having the smallest bladder can really be serious though......like....on a road trip.