Why will a diver become less buoyant as he swims deeper?

[H2Andy]

i don't know, man... i'm drinking whisky!

 

[Damselfish]

Didn't realize that til after I posted....The details as to why is what was being asked..

<currently writing on the chalkboard 100 times "I will not post before I read context of the question" >

think we could get that in the TOS?

 

[Divmstr223]

think we could get that in the TOS?

LOL...it sure should be in there.....

 

[meekal]

well dere ya go..... the 'differences' in all the 'correct' answers is what was making ME confused as well...

i was gonna go with "BECAUSE YOU'RE CLOSER TO THE CENTER OF THE EARTH"

 

[Reef Man]

Wow....we are all taking notes now!!!!

 

[markfm]

Even the "properly weighted" diver needs air in his BCD. You can dive naked for all it matters (watch out for the jellyfish).
Properly weighted normally means you have enough weight so at the end of the dive you're neutral, whether at 500 psi (common teaching) or 0 psi (I prefer that -- if it hits the fan, I would rather not have an uncontrolled ascent at the end). That means you're -5 or -6 lb at the start of a dive when using an AL80, so would need a little air to be neutral at the start (about 1/10th of a cubic foot). Drop to 100' and that 1/10 foot in the BCD would have compressed to 1/40 foot -- you would need to add air to be neutral, get it back to 1/10 foot.
(You'll have used some air on descent, so you won't actually need quite that 1/10th cubic foot any longer, but will still need some air in there.)

 

[Walter]

Even the "properly weighted" diver needs air in his BCD.

You are mistaken.

You can dive naked for all it matters (watch out for the jellyfish).
Properly weighted normally means you have enough weight so at the end of the dive you're neutral, whether at 500 psi (common teaching) or 0 psi (I prefer that -- if it hits the fan, I would rather not have an uncontrolled ascent at the end). That means you're -5 or -6 lb at the start of a dive when using an AL80,

It is very easy to compensate for those 6 lbs with lung capacity. I do it on almost every dive - no air in my BC.

so would need a little air to be neutral at the start (about 1/10th of a cubic foot). Drop to 100' and that 1/10 foot in the BCD would have compressed to 1/40 foot -- you would need to add air to be neutral, get it back to 1/10 foot.
(You'll have used some air on descent, so you won't actually need quite that 1/10th cubic foot any longer, but will still need some air in there.)

Nope. If this were the case, it would be impossible to dive w/o a BC - something I do when diving vintage and something everyone did prior to the invention of BCs. Look here and here for some examples.

 

[captain]

I am always amazed by people who think a BC is always necessary. In the beginning I dove for years without a BC,they weren't yet invented and I still do whenever the dive conditions don't require it which is 75% of the time.

 

[RiverRat]

I am always amazed by people who think a BC is always necessary. In the beginning I dove for years without a BC,they weren't yet invented and I still do whenever the dive conditions don't require it which is 75% of the time.

I've also tried in vain to explain it to divers. The industry just pounds it into them that you can't function without a BC. Mention lung volume and it's like a deer in the headlights I rarely add any air to my wing (another deer moment) when tropical diving (or even when diving dry although I need some more dry dives in to get better at it). Occasionaly I add a blast if I've overweighted myself a bit, like with add-on gear or something. Or if I'm in a strong downward current on a wall and want a little help until I get shallower (and un-narced).

 

[Barracuda2]

I am always amazed by people who think a BC is always necessary. In the beginning I dove for years without a BC,they weren't yet invented and I still do whenever the dive conditions don't require it which is 75% of the time.

Right On, Captain!!--I think it's a conspirancy by the BCD manufacturers!