Wing vs. Jacket

[Lobzilla]

I tried a backplate/wing set-up last weekend. I found that my trim was terrible...I was very "head down" and kept rolling over on to one side. I know I can move the tank to deal with the "head down" attitude but I'm at a loss as to why I couldn't control the "rolling".

At the time I thought that perhaps with all my weight in the back plate there would be a natural tendency to "turtle" but my son (and the other divers) were fine.

Is it possible that the "loaner" just wasn't fitting me properly...the straps did seem a wee bit loose? It was a sinlge tank set-up and the diver who loaned me the rig said it is much easier to use a BP/wing with doubles.

Bob (Toronto)

Being a newbie with little practical experience I try to approach these problems from the scientific angle.

Rolling over sideways into the "turtle" position means that your center of buoyancy (CB) is lower that your center of gravity (CG) when you are horizontal. Maybe you were wearing a more buoyant suit than your son or your body mass index is less favourable .

Bottom line is that you have to lower the center of gravity in your horizontal plane. Pulling the tank closer to your back (i.e. down in the horizontal attitude) is going to help and so is adding weight pockets to your straps. Adding weight to the plate is going to make things worse in your situation.

The ideal trim would be to have CG and CB at exactly the same point like the NASA astronauts in the training tank. Then you can "hang" neutrally stable in any position.

 

[Amphiprion]

To the OP. While I don't dive in cold water that often and don't use a drysuit, from my understanding, cold water divers using a single tank wing often opt for a larger single tank wing, such as one with around 40-45 pounds of lift. I believe the reasoning is that in the event of a drysuit failure, you can still swim up even though you may be wearing lots of lead. You can still use this wing for warm water diving however.

 

[SangP]

I tried a backplate/wing set-up last weekend. I found that my trim was terrible...I was very "head down" and kept rolling over on to one side. I know I can move the tank to deal with the "head down" attitude but I'm at a loss as to why I couldn't control the "rolling".

At the time I thought that perhaps with all my weight in the back plate there would be a natural tendency to "turtle" but my son (and the other divers) were fine.

Is it possible that the "loaner" just wasn't fitting me properly...the straps did seem a wee bit loose? It was a sinlge tank set-up and the diver who loaned me the rig said it is much easier to use a BP/wing with doubles.

Bob (Toronto)

Having said that my *guess* would be the rig you borrowed was too loose.
Tobin

I agree, there are several reasons and for myself the first time I used one, I was at a 45 degree angle upwards... feet heavy.

I was also having problems as I was constantly moving off to one side.

With a bp/w weight positioning is very important and I later found out that a couple of weight pockets or just threading a couple of weights to the upper tank bands helped trim me out perfectly.

I your case, perhaps you could try a weight belt or did you have just too much weight but in the wrong places. Lastly get a pair of jets they will certainly prevent head down syndrome !

SangP

 

[Sponon]

I think I finally found my BC; Halcyon Infinity MC System.

I want to thank everyone who participated in my thread. If it weren`t for you, I would probably end up with an entirely different rig. Thanks a lot

Now I need to find myself a regulator....

 

[DiverLaura]

I think you will LOVE the Infinity!!! Look forward to hearing your experiences after you get it!!! (and we want PICTURES!!!)

 

[jepuskar]

 

[Sponon]

hahaha... Great movie, jepuskar

 

[mictrik]

I completely disagree with "why a backplate and wings" representation of a jacket or "stabilizing jacket BC. The stabilizing jacket provides air cells that are fully connected and and fill around the tank too. the Air "bubble can always get to the highest point providing stability in every position. Horizontally the air bubble is around the tank, when vertical it is at the shoulders, if upside down (YES) the bubble is at the bottom of the BC around the tank. No other buoyancy compensation device acts like this. The article refers to "jackets" and it is either very wrong or it is not considering the Scubapro stabilizing jackets where every part of the jacket contains air space. The advantage of backplate and wings is simple... You get more room in front because the bladder is totally at your back. You have more room for hooks to carry tools and less bulk up front to work with tools. At the same time you get excellent horizontal stability with extremely secure tank harness. Though Scubapros stab jackets have a great tank harness too. I use both and think that the Stab jacket is the best for most diving. With regard to being squeezed by the jacket... LOL! I say lose some weight and learn how to weight out properly. When I wear a jacket you will not notice any air in it unless I am on the surface for some reason.

 

[jepuskar]

hahaha... Great movie, jepuskar

Thanks. I need to redo the in water stuff as my skills have improved and this should silence some of the diehards out there....but not all.

 

[DrunkenParrot]

EPIC VIDEO Must be posted for every BP/W VS BC thread from now on.