Milton Waddams wrote:
Which is more accurate to use in estimating leeway, the true
wind/current or the apparent wind/current?


Milton
How do you tell the difference between "true current" and "apparent
current"? How do you measure either?

And leeway is a function only of the wind, not of the current.

Traditionally, and by that I mean going back a few hundred years to
the square riggers, leeway guesstimates were based not on wind
strength, but on the amount of sail you had to take in. Bowditch
summarizes several other earlier writers and claims:
"1st. When a ship is Close-Hauled, with all her sails set, the water
smooth, and a moderate gale of wind, she is then supposed to make
little or no lee-way.
2d. Allow 1 point, when the top-gallant sails are taken in.
3d. Allow 2 points, when the top-sails must be close-reefed."

Nowadays, if you did it at all it would be based on the tables
generated by a "Velocity Prediction Program," the same software that
generates polar diagrams. These tables are usually organized by true
wind.

"Jeff" wrote in message
...
Milton Waddams wrote:
Which is more accurate to use in estimating leeway, the true
wind/current or the apparent wind/current?


Milton
How do you tell the difference between "true current" and "apparent
current"? How do you measure either?

And leeway is a function only of the wind, not of the current.

Traditionally, and by that I mean going back a few hundred years to the
square riggers, leeway guesstimates were based not on wind strength, but
on the amount of sail you had to take in. Bowditch summarizes several
other earlier writers and claims:
"1st. When a ship is Close-Hauled, with all her sails set, the water
smooth, and a moderate gale of wind, she is then supposed to make
little or no lee-way.
2d. Allow 1 point, when the top-gallant sails are taken in.
3d. Allow 2 points, when the top-sails must be close-reefed."

Nowadays, if you did it at all it would be based on the tables generated
by a "Velocity Prediction Program," the same software that generates polar
diagrams. These tables are usually organized by true wind.


Maybe he's thinking of set and drift...


--
"j" ganz @@
www.sailnow.com

"Capt. JG" wrote in
:

"Jeff" wrote in message
...
Milton Waddams wrote:
Which is more accurate to use in estimating leeway, the true
wind/current or the apparent wind/current?


Milton
How do you tell the difference between "true current" and "apparent
current"? How do you measure either?

And leeway is a function only of the wind, not of the current.

Traditionally, and by that I mean going back a few hundred years to
the square riggers, leeway guesstimates were based not on wind
strength, but on the amount of sail you had to take in. Bowditch
summarizes several other earlier writers and claims:
"1st. When a ship is Close-Hauled, with all her sails set, the water
smooth, and a moderate gale of wind, she is then supposed to make
little or no lee-way.
2d. Allow 1 point, when the top-gallant sails are taken in.
3d. Allow 2 points, when the top-sails must be close-reefed."

Nowadays, if you did it at all it would be based on the tables
generated by a "Velocity Prediction Program," the same software that
generates polar diagrams. These tables are usually organized by true
wind.


Maybe he's thinking of set and drift...


LOL..... exactly why I stayed away from this one

otn