Info The "Ultimate" wing lift calculator :)

[lemon]

I searched the thread and couldn't find an answer to this...

where is the negative buoyancy of the regulator factored in on this spreadsheet?

 

[Scared Silly]

Under the regs/lights/misc column (D29 under my version)...

 

[no excuses]

for a trilam suit with 300 gram insulation how much should I figure for my suit bouyancy without going down to the pool? How full of air should I make my suit for testing this, I would guess that I would empty my suit of as much air as I can?

 

[selytch]

It's little more complicated for dry suits.
The dry suit should not be used for flotation, hence its buoyancy should be 0 (worst case flooded suit).
On the other hand the suit is positive on the surface, undergarment/inflated air.
So:
A. To calculate min needed wing volume I put 0 and 0 in suit (surface/compressed at depth) (see C).
B. To calculate amount of lead needed I put 12-16# for surface and 0 for compressed at depth.
C. To be safe, add A+B and use this number as required wing lift.

Make sure to try the gear out in confined water first!

 

[BB1]

Hi,

This is an awesome calculator to give me a rough starting weight for BP/W setup however I don't use a dry suit as its never cold enough here.

Would you or anyone have any buoyancy figures for 3mm (normal) and 5mm (mid winter) wetsuits?

The calculator seems to suggest I need a lot less weight. In a 3mm with a jacket BCD and AL80 I needed 18#'s in sea water but the calculator reckons 2.4#'s?? I know I am a big fella - 6'4" and 240lb's so need more lead but I am trying to work out how I enter or use that info with the calculator?

Any help appreciatted and big thanks for writing the calc - it helped me to understand the relationship between wing and weight better.

I realise the figures will vary depending on the suit manufacturer and age etc but it would give a good start.

 

[selytch]

Thanks a lot for the feedback!
I guess I can add "non compressible" weight field, which for now can be added to the wetsuit field, same value for surface and depth.

I assumed that average human body is neutrally buoyant. But you are right, this may not always be the case. I'll try to find some data to integrate into the spreadsheet.

 

[BB1]

I'd gues that the human body is neutral as well.

Pool test just in boardies:
Full breathe = Head above water
Half breathe = eye level at water level
All breathe out = sink

I'm assuming that the XXL or XXXL (mostly height honest!) wetsuit accounts for a large proportion of the 18# lead and the Calypso Jacket BCD = most of the rest!

 

[jimbob394]

thanks that helps a lot!

 

[fjpatrum]

I'd gues that the human body is neutral as well.

Pool test just in boardies:
Full breathe = Head above water
Half breathe = eye level at water level
All breathe out = sink

I'm assuming that the XXL or XXXL (mostly height honest!) wetsuit accounts for a large proportion of the 18# lead and the Calypso Jacket BCD = most of the rest!

By contrast, my pool test in a 2.5mm long sleeve shorty
Full breathe = sinking slowly
half breathe = sinking faster
all breath out = sink disturbingly fast

I'm 6'1 and weigh approx 165-170 pounds.

 

[selytch]

Fresh water (1.000) is less dense than seawater (1.028). Human body density is closer to seawater. I guess 3% difference is 5#, which accounts for your observation...