Please, check my numbers from the "Ultimate" wing lift calculator...

[Olalj123]

Hi,

I apologise in advance for these questions but I'm a rookie when it comes to calculating buoyancy and weight requirements and I feel it is important to get it right.

BTW, I've used fresh water weights for my tank (I figured as an added safety margin). I found the numbers on Cylinder specifications | Silent Planet

Alright, here are the numbers... Head weight: -10 lbs (as stipulated, about - 4,5 kg)

Tank full: -15,8 lbs (12 litre 300 Bar steel tank, -7,2 kg)

Tank end of dive: -6,3 lbs (12 litre, 300 Bar steel tank, -2,85 kg)

Exposure suit: +26 lbs (Dry shell suit with rather heavy liner, about +11,8 kg. This is the number that I am most uncertain of; I've calculated using the "Ultimate" wing lift calculator based on the gear (tank, lead, suit I used on my dry suit course, but I may have been a bit heavy)

Non buoyant gear: -9 lbs (as stipulated, back plate and reg/octo, about -4,1 kg)

If I use the non integrated weight setting I get a result of need lift 24,8 lbs (about 11,3 kg)

If I use the integrated weight setting I get a result of need lift 35,5 lbs (about 16,1 kg)

The need lead result is 10,7 lbs (about 4,8 kg)

So, do the numbers make sense?

The next question is, would a wing with a lift capacity of 32 lbs (14,5 kg) be sufficient provided I do not use an integrated weight system, or is it too small even then?

Thanks for any help!

Ola Ljunggren, Sweden

 

[Kern]

At the beginning of the dive your rig is negative, 16lb (tank), 9lb (BP, etc.) ~ 25lb. You need a wing that will float this without you in it.


At the end of the dive, you're negative about 15lb. You'll need to add about 12/13lb of led to remain neutral at your safety stop with a suit thats 26lb positive.


If your suit is 26lb positive, your wing will have to be able to compensate for complete loss of buoyancy due to flooding.


A 32lb wing will compensate for a drysuit flood, (up to 26lb may be lost), & it will float the rig at it's heaviest point in the dive, 25lb, for non integrated weights.

Once you integrate the weight into the rig, at it's heaviest, it now weighs up to 38lb & your 32lb wing won't keep it at the surface if you need to ditch it.

 

[Olalj123]

Kern,

So, just to be sure: If I don't use integrated weights a 32 lbs wing will be sufficient?

Thanks

Ola Ljunggren, Sweden

 

[Kern]

Yes..

 

[Olalj123]

Kern,

Thank You!

Ola Ljunggren, Sweden

 

[NAM001]

TAKE A LOOK AT THIS IT WORKS FOR ME. http://admin.minus-mp3.com/Bouyancy_calculator.xls LOOK AT YOUR TANK BOUYANCYS THEY MAY BE OFF A BIT IN THE SPREAD SHEET. BE SURETO ONLY PUT IN SINGLE TANK WEIGHT AND SET THE DOUBLES FIELD TO MAKE IT CALCULATE FOR DOUBLES.