Sail ship maneuvers
Sail ship not tacking (Proto credit: Wikipedia)
Maneuvering a sailship is not straight forward, especially when against the wind.
This article is focused on sail position when turning for
The main sources are naval action videos.
The sailship has 2 or 3 masts.
The fore-mast (the one most ahead) and the mizzen-mast
(the most rearward) are moved independently. The mainmast (the one in the center on
3 masted-ship) move with the rear one. I don't know why, it may be because it
is located aft of the center of gravity, but I (still) don't know if
this affirmation is true.
For the rest of this article, let's assume the ship's captain wants to turn to
the right (star board) and want to do it without using the rudder.
The different steps will be marked as follows:
- step 0: beam reach, turning into the wind
- step 1: close hauled, turning into the wind
- step 2 and 3: into the wind, turning towards beam reach
- step 4 and 5: bread reach to running with the wind
- step 6: running with the wind turning towards bread reach
- step 7: getting back to step 0
Tacking cover steps 0 to 3.
Bracing must be done as follow:
- fore-mast: neutral. No forces inducing turn act on this mast.
- mizzen-mast: forward. Forces acting on this mast tend to make the ship turn to starboard.
The fore-mast must be maintained as parallel to the wind as possible.
In that position, the ship can hardly move.
The wind will push the sails from the head of the ship (quite unusual)
It must be braced as follow:
- fore-mast: as if the wind comes from starboard. That way the wind push this mast to the starboard
- mizzen-mast: as if the wind comes from port. The wind will push this mast to the port
It consists in maintaining mizzen-mast as parallel to wind as possible.
At that step, the fore-mast may be braced forward again.
Wearing cover steps 4 to 7
This is the counterpart of step 0. The ship is braced as follow:
- fore-mast: forward. Forces acting on this mast tend to make the ship turn to starboard.
- mizzen-mast: neutral. No forces acting on it.
Counterpart of step 1.
- fore-mast: forward
- mizzen-mast: as parallel to wind as possible.
Counterpart of step 2.
- fore-mast: as if wind comes from port
- mizzen-mast: as if wind comes from starboard
The effects are the same as in step 2.
As in step 0, the fore-mast must be as parallel to the wind as possible.
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