Bouyancy Control - Wing or suit?

Janos

I'm curious to know how people control their bouyancy when diving CCR. Obviously this depends a bit on how you controlled your bouyancy on OC, hence the options.

Janos

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DonalWalsh

When diving twins/stages I used a combination of wing and drysuit- using the suit exclusively means creating rather larger a bubble of gas around methan I like to control. Since diving the Meg I rely on the wing far more and only use tiny amounts of gas to keep squeeze off - to illustrate a 1.5l suit inflation bottle is doing 8-10 dives.

Padowan

In my OC days, I used the wing for bouyancy, and the suit only for squeeze. With full tins, there was a lot of gas weight you needed to compensate for at the start so the wing is needed to hold this volume of gas (IMHO). I have a neoprene suit, and so I lose bouyancy in this as I go deeper. My weighting is pretty much spot on, when holding a 6m stop, I have a tiny bit of air in the suit and nothing in the wing, but I don't feel comfortable with the feeling of swilling around in a suit full of air, so I still use the wing on the CCR too.

One thing I'm still undecided about is how much of my kit I should consider "ditchable" and therefore set my bouyancy to be correct without. My "spot on" weighting is without stages or any tools all of which I consider I may ditch so have to leave them out of the equation - the combined weight of all this lot could be as much as 4kg (~1kg for each sidemount, ~2kg for a lump hammer, chisel and crowbar) negative in the water, which combined with the suit squeeze, gives a lot of weight to compensate for and therefore necessitates the use of my wing.

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Digger

I used to dive for years using the suit for buoyancy on OC, then started doign dives with a decent sized twinset and stages and it just became unmanageable. I started using the wing and couldn't believe how easy it became, and my trim was a thousand times better.

Now with the unit the buoyancy change is minimal, and I find using the suit fairly easy to do, and there isn't a lot of gas in there. I only have the stages I could need to remove, and they're only a couple of kilos difference.

I find myself weighted so that without removable gear I could dive and hold a stop, but I would either be a little bit squeezed on the suit or would get a very slightly short breath. It wouldn't be difficult, just a little cold in the drysuit probably. I'll trade this off for having less gas flying around suit/wing and having more weight. It's probably about 2kg difference. THe chances of having to remove stages and things is minimal, and I've done it by choice a couple of times out of a whole lot of dives so far, but not to a point it makes a massive difference. Slightly different with tools which can be easily lost when working underwater, so I'd be weighted ads per normal and the tools on top of that.

Digs.

edster

For me, with twins and stages theres no quesiton of doing it on a suit, the amount of air required is just ridiculous, and in a neoprene well fitiing suit, just isnt going to happen! However now I'm on the box, I dive with the wing empty and just use the suit, with one 7l stage this is no problem at all. My initial popping up to the surface on training convinced me that controlling 2 sources of gas (loop and suit) has got to be easier and hence safer than 3. At this point in time, theres no way i'd change although if I had twin steel 10s as stages I might start running some air in the wing. I cant convince myself that three bubbles is better than two !

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AD_ward9

You have no option for people who use both the suit and the wing.

That option is virtually mandatory if you use a thick neoprene drysuit, like a Unisuit, even though the instructions with it say otherwise. Using a Unisuit, I use the suit down to 100ft (30m) then use the wing.

Cheers,
Alex

Andrew-John

As far as I can see, water temperature has a role in finding out proper strategy here.

Theoretically speaking a good procedure (OC and CCR) could be to fill the suit only to such extent that you feel comfortable and by using the much more accurate wing for balancing as well as maintaining the MLV.

However in cold water the heat loss has to be decreased by using argon as suit gas. You feel cold down there if you don't move enough (camera operation etc). So its time to push more argon into the suit and release dilluent from the wing correspondingly.

In the Nordic countries water temperature under the ice at decompression depths may vary between 1,5..4 oC. The only practical way seems to be to empty the wings totally, catch the bail out decompression cylinders to be heavier, maintain MLV and flush the suit with argon and keep it filled up as much as possible during the decompression. Even this is sometimes not enough to prevent partial hypothermia. Thus we have to arrange lines or use other arrangement to be able to swim and keep warm during the decompression.

Summary, both suit with argon and wings has to be used in cold conditions. Maybe wings could have the priority in the beginning and suit during the end of the dive?

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nigelh

I use the wing for control but today I moved so much gas to the suit to counter the 5C water temperature I was effectively diving the suit. Using the suit is a bit edgy in 4 to 7m but I didn't do anything too silly.

Horsea Island isn't my favourite dive site but we were doing 'full contact' rescue drills.

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caveseeker7

OC - suit to 30 m, wing after that
(single, don't dive twins without Rebreather between)
CC - suit to 20 m, wing after that

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Louby Lou

I used to fly my suit over here in the UK, but then I gave up diving in the UK and ditched the drysuit

I got so used to controlling my buoyancy using my BC or wing that I've found it difficult to switch back to using the suit and fly the wing instead; plus a couple of feet first ascents earlier on in the year when I was getting used to diving the drysuit again after 10 years knocked me a little.

On my MOD1, I flew my wing and got on well with it. I do want to try and use my suit to control my buoyancy a bit more rather than using my wing. At the moment I use air in my suit just to take the edge off the squeeze

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