Sail ship maneuvers

Tue 19 February 2019
tallship 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 full-rigged sailships. The main sources are naval action videos.

Preambule

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

Tacking cover steps 0 to 3.

step 0

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.

step 1

The fore-mast must be maintained as parallel to the wind as possible.

step 2

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

step 3

It consists in maintaining mizzen-mast as parallel to wind as possible. At that step, the fore-mast may be braced forward again.

Wearing

Wearing cover steps 4 to 7

step 4

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.

step 5

Counterpart of step 1.

  • fore-mast: forward
  • mizzen-mast: as parallel to wind as possible.

step 6

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.

step 7

As in step 0, the fore-mast must be as parallel to the wind as possible.

Category: how to Tagged: nautical how to boats Sailship Tallship


Conference posters

Fri 11 December 2015

[caption id="" align="alignright" width="75" class="zemanta-img"]English: This mindmap (Mind map) consists of r... mindmap needing clarification (Photo credit: Wikipedia)[/caption]

Few weeks ago, I wrote about mindmap in [latex]LaTeX[/latex]. Now I want to precise few ideas and to have all key ideas visible in one sight. I think the best layout is similar …

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