Re: [PSUBS-MAILIST] Center of gravity Vs. Center of Bouyancy

[Ed Greany <crest25@attglobal.net>]

Adam,

I don't think I have heard of "Center" of bouyancy unless you are
referring to "Neutral" bouyancy. Neutral bouyancy is that point where a
sub neither raises or descends but its weight is equal to that of the
water it displaces for a particular depth. This is what every sub
strives for while underway and not intentionally diving deeper or coming
up. It is a constant depth where the diver/sub capt neither has to add
ballast nor discharge ballast.

Center of gravity is the centerline midpoint at which the trim fore and
aft is balanced if you were to suspend it from a cable in the air at
that point. It is like a balanced scale = both ends level. This is
usually close to the middle between the bow and stern but because
equipment, passengers, or ballast is heavier toward one end, it is not
usually exactly midway.

Ed

Adam wrote:
> 
> Hi,
> 
> Thanks for the responses on the active SONAR guys.
> 
> Now, I haven't purchased a principles of sub-design book yet because
> they are kinda hard to get where I live.  So here is a rudementry
> question.
> 
> What is the difference between center of gravity and center of
> bouyancy?
> 
>