Hi Ray. I imagine piloting through "total blackness" with no instruments
is nerve wracking. I'm looking forward to seeing the little piezo electric
sonar device at this years convention that David's been designing. Should have
some real benefit during those times when visibility is nil.
On VBT's..... how do we size that tank? My sub will weigh around 6700 lbs
on land. With room for two people, but often with just me inside. I wouldn't
have a problem with loading/unloading some lead ballast but I still want a VBT
for small adjustments. Is there a rule-of-thumb on a percentage basis or
something that is accepted as the norm? Needless to say, room inside is a
concern for a hardened tank, which will take up considerably more space than
just it's internal volume. I was thinking something like an extra aluminum
scuba tank would be enough, and would tuck neatly into an area near the
bottom. If something much larger is needed, then the best option seems to
locate it outside. That means extra plumbing and more drag when
moving.
Another question, how do the guys know how much water is inside it? I was
thinking that with the tank inside, I could fab a spring loaded sling for it,
and approximate it's weight with a dial indicator on it's total weight. ( I'm
trying to keep all the systems as " electronic free " as possible. ) I suppose
a sight glass would be possible, but I'm just not that comfortable with that
idea. The sling would only have to have an inch or two of travel,
and could be calibrated fairly closely to indicate the water volume in there.
First though, gotta know how big it needs to be. Any thoughts on this ? Frank
D.