"Gary" wrote in message
r.com...
OK...I know...this is probably a stupid question, but then again you know
the old saying about the only stupid question is the one that goes
unasked,
so here goes.

I always assumed that the draft of a boat was...for lack of a better term,
how deep it ran in the water at the lowest point. I am purchasing a boat
right now, and the survey results listed the boat as having a DRAFT of 3
feet, but a DEPTH of 5 feet. I kinda assumed these were the same thing,
but
obviously I was wrong.

I can only imagine now that the draft must be the how deep the hull runs
and
the depth must be how deep the rudders / wheels etc. run.

Am I even close?

Thanks!

Draft is explained as pertaining to the lowest part of the hull, measured to
the water line, and can vary depending on how much weight is on board, and
where its placed. Some claim it can change for a planning hull, while on
plane, but I have always heard it measured "at rest". Running gear is
normally not included, but I know many folks (mostly smaller craft owners)
who claim their draft, is the lowest part of the boat period.

I've never heard of "depth", but Ill assume that is the lowest part of the
running gear...providing its lower than the hull draft. My ski boat, for
example, has a draft of about 12". Add the running gear, and my lowest point
is 26". Now my jet boat has a draft of 10"...and that the lowest point of
the whole boat...running gear included. It can also transverse 5" of water
at speed, but I've never done it.

I/Os and outboards can of course vary their lowest point, by trimming up. I
see this being done all the time in the canals, as not to tear up their
prop, but they also give up some controllability when they operate that way.

And of course big displacement ships like liners and tankers, draft is the
draft, as their running gear is "behind" the hull, and does not protrude
below it.


--
-Netsock

"It's just about going fast...that's all..."
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