"John Bell" wrote in message m...
2. We know it's possible for an aircraft to fly at angle to the
direction in which it's pointing. Does anyone know why does such a
thing not happen in boats or ships? After all, both ships and
aircrafts use media to float on... any sailors here could answer that,
I guess

In addition to the issue of boats traveling through water with a current,
there is actually the issue of sailboats traveling through the water at a
different angle from which they are pointed due to the push on the sail.
This slip angle creates an angle of attack on the centerboard, daggerboard,
or keel to provide an opposing force.

As a sail boat buys I take issue with the comment "push on the sail".
"Pushing" on the sail is your last choice and used only when sailing
directly away from the wind. However, this is the way the old 1400's
sailer did it. Today we have sails that are airfoils so the air
"sucks" us around. In fact you will move MUCH faster when sailing up
wind than when sailing down wind.
-Robert