Joe wrote:
Geeze Rick, For someone playing tugboat capt instead of being one you
have lots of room to talk right.

TPI = 1/35 (A x1/12) =A/420 where A is the
waterplane area for a particular draft in square feet.

The ship was approx 250 foot est 300-500 tons empty.
A cord of Oak weighs 2 tons.

Thats 260 tons cargo shipped aboard.

Like I said a flik flub but no the less a good story.

Jeff your the wannabe..... know it all..... smart lipped..tugboat
trash.


Joe
USMM Master # 607529


Just for the fun of it, pick a beam you consider consistent with the
length you give (ignore hull shape, we'll consider her a boxy old tub),
and using your formula and weight loaded, see what you get for change of
draft.

45 foot beam it is. What do you get as a change in draft?
And is she sitting below her Pilsom mark?

Joe

Shall we consider LCF and VCB?

And we are talking long tons right? Since it is lumber.
Salt water right?

Joe

Joe wrote:
Shall we consider LCF and VCB?

And we are talking long tons right? Since it is lumber.
Salt water right?

Joe

G We're only interested in how much the ship will sink bodily.
Long tons are always used (unless he's using metric, but then it
wouldn't be TPI) and yes it's salt water.
Using your numbers I get only a small change, but I'm still waiting to
hear what you get, since I asked the question.

otn

But what about LCB & VCB?

The freighter was a stern engine room scamp with center and forward
cargo holds.

Shall we just say that she will load level?

Joe

Joe wrote:
But what about LCB & VCB?

The freighter was a stern engine room scamp with center and forward
cargo holds.

Shall we just say that she will load level?

Joe

The question was about TPI which meant we were only concerned with
"bodily" sinkage, not trim.
One factor to consider is that since this was to be fuel and the ship
was a midship house freighter, the Captain would probably load it close
to the midships area, so there would be little affect on trim.
In truth, the question was bogus.
Without the Hydrostatic curves/tables,deadweight scales and knowing what
the draft was, prior to loading the wood (wet or dry?)for the particular
ship in question we really couldn't give an accurate answer.
However, as a "fun" exercise, if we took the formula you gave TPI=AWP/420
TPI= 250x45/420=26.8 tons to submerge 1"
Total fuel loaded was 260 tons
Total bodily sinkage= 260/26.8= 9.7"
Obviously, this is bogus, since we know the ship is not a box, but if
you want, reduce the AWP by 1/2 and see what you get.
The main point was/is that 260 tons is not really all that much weight
added,. for a ship.
The other possible problem in looking at your original statement was
that you stated the vessel tonnage as between 300-500. What tonnage were
you estimating? If this was gross or net it didn't give an indication as
to weights and is probably low, anyway.

otn