16kg lift enough for cold water dive?

[kckskh]

Hi, i have a Seac Sub Icaro which has a 16kg lift and i will be diving in UK for a couple of years from September onwards. Any idea whether 16kg lift is enough for a water temp of about 10 or even sub 10 degree celcius?

 

[Kim]

Won't that depend on what else you are diving with? Wetsuit thickness, or drysuit - single tank etc. I should imagine though that if it's enough for you now, as long as you don't change your tank setup drastically, it'll be OK there.

 

[scubamate]

Are you planning on overweighting yourself by 16KG? If you are neutrally buoyant there should be "zero lift" required. As to air space compression of the wet suit, etc. Again, get neutral at the surface, then you will only be adding small amounts of air to the BC as you descend to maintain neutral buoyancy.

 

[Sonny_PL]

I agree with Kim and Scubamate, Your buoyancy depends on what you have / ware (wet suit / dry suit, how many tanks etc.) Remember that in Europe we use steel tanks...

 

[jonnythan]

It's enough.

 

[jonnythan]

Are you planning on overweighting yourself by 16KG? If you are neutrally buoyant there should be "zero lift" required. As to air space compression of the wet suit, etc. Again, get neutral at the surface, then you will only be adding small amounts of air to the BC as you descend to maintain neutral buoyancy.

This is not very good advice.

The wing needs to have enough lift to offset all the buoyancy lost by suit compression plus the total weight of the gas in your tanks.

 

[Gary D.]

Yes it's plenty even with two weight belts and some :^)

Gary D.

 

[Tassie_Rohan]

Hi there -

16 kg (35 lb) is fine. Half of that is way way more than enough to counter the loss of buoyancy in your wetsuit with depth and the additional weight of gas in your tank at the start of the dive. If you are diving wet expect lets say a 6-9 lb maxiumum loss in bouyancy in a cold water wettie going from surface to 40+ metres, while the additional air at the start of the dive should weigh in at an extra 5-6 lb or so...

However - those extra pounds of lift really come in handy on the surface. If you have your weights on your BC, a full steel tank with lights and other assorted paraphilia clipped on you may need 20-25 lbs lift just to make sure your kit floats on the surface when you take it off. It can be somewhat embarrassing to chuck your kit in the water for a in-water gear up only to watch it slowly sink down to Davey Jones and friends...

With a single tank I use a 30 lb wing - I find its great under water but on the surface in rough seas in a wet suit I found myself wishing I had 35-45 lb lift just to get a bit higher in the water. Now that I dive dry I just blow up the drysuit on the surface...

So yep - 16 kg lift is ideal.

Cheers,
Rohan.

 

[scubamate]

Why? Proper weighting is a must. Realistically, you should not need to add air to your BC at the surface to remain there. You add the air to make you positive at the surface so you can rest and not over exert yourself, or to make up for compressed air spaces as you descend. Yes you need a certain amount of lift to keep your equipment afloat if you take it off in the water. If your equipment is 15 pounds neg, then you need 15 pounds of lift to keep it floating. (actually 16, 15 to be neutral + 1 to become positive)

 

[Tassie_Rohan]

Why? Proper weighting is a must. Realistically, you should not need to add air to your BC at the surface to remain there. You add the air to make you positive at the surface so you can rest and not over exert yourself, or to make up for compressed air spaces as you descend. Yes you need a certain amount of lift to keep your equipment afloat if you take it off in the water. If your equipment is 15 pounds neg, then you need 15 pounds of lift to keep it floating. (actually 16, 15 to be neutral + 1 to become positive)

True - proper weighting is a must - at the end of the dive with the BC empty you should be floating around eye level on the surface, sinking a bit on exhalation, while with an empty bc at the start of the dive you're slightly negative (say -5 lb) thanks to the weight of air in the tank. The weight you have on should be just enough to counter the buoyancy of your wetsuit at the surface and the buoyancy of an empty Al tank, and not a pound more.

During the dive you may only need to use around 3-10 lb lift depending on the change in wetsuit thickness with depth and the amount of air in the tank.

The amount of lift required on the surface for comfort is a totally different, and very subjective matter. If I was only 1 lb positive on the surface I would have trouble keeping my head above water. 30 lbs lift on the surface will get your head and the top of your shoulders above water and is comfortable in most situations. I find, and this is a personal and therefore subjective mater, that with 30 lb lift on the surface (remember that i'm nearly neutral and floating at eye level with 0 lb in the bc) it is still uncomfortable when dealing with the heavy swells found around Tasmania’s coast: that extra bit of elevation gained with a bit more lift can really help with your view of the world when you’re being knocked around. But true: 1 lb positive on the surface and your are afloat: just maybe not that comfortable.

Cheers,
Rohan.