Diving Doubles?

[karstdvr]

I use the Trek wing for sidemount,although I used to use the Jr wing with single tank or AL80 doubles

Lloyd Bailey used to sell Sea Tec

 

[Jason B]

LOL!!

Horseshoe shaped wings can trap air. Think about this. You're horizintal in the water, just like the book says you should be. You have air in the bladder of a horseshoe wing. How does air get from one side of the tank to the other? It goes across the top. So if you roll to your left, the air goes uphill to the right side, and vice versa. Problem. Assume you are slightly head down. Like you were looking down at something, or checking your weights, or your pocket, or something. Now the air won't travel side to side because it's stuck down on the prongs of the horseshoe. In order to get the air to move, you have to go slightly head up and roll. With a donut bladder, that air COULD just go around the bottom of the wing. Problem solved.

You sound like you are on a mission to convert everyone over to donut wings...
Here goes a comment Tobin made over on TDS.

"From a side to side gas transfer standpoint I'm saying exactly that, donut = horseshoe. To get gas to pass through the lower connection one need be distinctly head down."

Link the whole thread for those interested...
http://www.thedecostop.com/forums/showthread.php?t=15430

As for Dive Rite wings, they can be purchased without the pull dump feature (plain elbow) and a shorter corrugated hose.

 

[cool_hardware52]

You sound ike you are on a mission to convert everyone over to donut wings...
Here goes a comment Tobin made over on TDS.

"From a side to side gas transfer standpoint I'm saying exactly that, donut = horseshoe. To get gas to pass through the lower connection one need be distinctly head down."

Link the whole thread for those interested...
http://www.thedecostop.com/forums/showthread.php?t=15430

As for Dive Rite wings, they can be purchased without the pull dump feature (plain elbow) and a shorter corrugated hose.

Yes Jason, that's my position on donuts vs horseshoe wings.

If you picture the horizontal diver using any wing, the wing will typically be filled to 20-30% of capacity at depth during normal use. Where is this gas distributed? In a bubble along each side of the tank(s) Why? because this part of the wing is free to fold up along side the tank(s). The top arc of the wing is held down by the valves and regulators. The bottom arc of a donut wing is held down by the lower end of the tanks.

To shift gas from one side to the other you need to make either the top arc of the wing, or the bottom arc of the wing the highest point. You can only do this by rasing either your head or your butt.

Dry Suit divers will already have a need to raise their shoulder a bit to vent the suit, this motion will fill the top arc of the wing. Pure "butt first" ascents don't allow for venting the suit.

The major advantage of a well designed donut wing is that some of the required lift volume can be "hidden" at the base of the wing. This allows for a narrower overall profile.

It is the narrow profile that makes the most difference in performance.

A narrow profile wing will "wrap" the tank(s) less when filled 20-30% in noraml use. Less tank wrap means the gas along side the tank(s) is only just barely higher than the top arc of the wing. This means you only need raise your shoulders slightly to shift gas from side to side.

Anybody who has used a doubles wing with a Single tank can tell you tank wrap (taco) makes venting difficult. Narrow designed wings, horseshoe or donut, vent better due to less wrap.

Tobin

 

[PerroneFord]

I'm not on a mission. I'm relating MY experiences. I dive both and own both. If the horseshoe works better for you, or for someone else, have at it. I was aware of Tobin's comments. Maybe he's a better diver than me. I just find the donut wings easier to dive.

I am aware the DR wings can be purchased optionally with the elbow and with a shorter corrugated hose, but they don't come stock that way. Why, I don't know.

You sound like you are on a mission to convert everyone over to donut wings...
Here goes a comment Tobin made over on TDS.

"From a side to side gas transfer standpoint I'm saying exactly that, donut = horseshoe. To get gas to pass through the lower connection one need be distinctly head down."

Link the whole thread for those interested...
http://www.thedecostop.com/forums/showthread.php?t=15430

As for Dive Rite wings, they can be purchased without the pull dump feature (plain elbow) and a shorter corrugated hose.

 

[cool_hardware52]

I'm not on a mission. I'm relating MY experiences. I dive both and own both. If the horseshoe works better for you, or for someone else, have at it. I was aware of Tobin's comments. Maybe he's a better diver than me. I just find the donut wings easier to dive.

Out of curiosity what horseshoe / tank combos have you used?


Tobin

 

[PerroneFord]

DR Classic w/ LP95
DR Classic w AL80s
Oxy 45 w/ LP95s
Oxy 45 w/ AL80s
Oxy 45 w/LP72s

 

[cool_hardware52]

DR Classic w/ LP95
DR Classic w AL80s
Oxy 45 w/ LP95s
Oxy 45 w/ AL80s
Oxy 45 w/LP72s

Thanks Perrone

Have you used a "donut" doubles wing?

I ask because it appears that you have used horseshoes with doubles, and perhaps a donut with singles.

What always interests me is folks that have used both horseshoes and donuts with doubles, and folks that have used both narrow horseshoes and donuts for singles.

Unfortunately this is a pretty small group, given the DSS narrow horseshoe for singles are the only wings I know of that fit that description.

Much more commonly I find people who have used horseshoes with doubles, maybe even used a wide doubles horseshoe with a single tank, then they get a chance to dive a dedicated, narrow, singles donut. Often this path leaves the impression that a donut wing is the magic answer.

Don't misunderstand me, donuts work fine, and offer some advantages in terms of reduced profile, I just don't think that gas shifts from side to side through the bottom arc as often as some people think.

Thanks for the info. I appreciate your willingness to provide the information and your actual in water results.


Tobin

 

[PerroneFord]

I've used the Halcyon Evolve 40 with AL80s. I found it much easier in most cases, but the dump location was hard for me because I was not used to it coming from my DR Classic.

I'll be diving your Torus 45 extensively this June, so I'll let you know. I'll back-to-back it with my Classic.

Thanks Perrone

Have you used a "donut" doubles wing?

I ask because it appears that you have used horseshoes with doubles, and perhaps a donut with singles.

What always interests me is folks that have used both horseshoes and donuts with doubles, and folks that have used both narrow horseshoes and donuts for singles.

Unfortunately this is a pretty small group, given the DSS narrow horseshoe for singles are the only wings I know of that fit that description.

Much more commonly I find people who have used horseshoes with doubles, maybe even used a wide doubles horseshoe with a single tank, then they get a chance to dive a dedicated, narrow, singles donut. Often this path leaves the impression that a donut wing is the magic answer.

Don't misunderstand me, donuts work fine, and offer some advantages in terms of reduced profile, I just don't think that gas shifts from side to side through the bottom arc as often as some people think.

Thanks for the info. I appreciate your willingness to provide the information and your actual in water results.


Tobin

 

[TheRedHead]

I used the Venture wing with double AL 80s in a pool. I'm not sure if I would do it in open water. I prefer a round wing over a horseshoe. I'm going to replace my RecWing.

 

[cool_hardware52]

I've used the Halcyon Evolve 40 with AL80s. I found it much easier in most cases, but the dump location was hard for me because I was not used to it coming from my DR Classic.

I'll be diving your Torus 45 extensively this June, so I'll let you know. I'll back-to-back it with my Classic.

Great!

Let me know how it works.


Tobin