Few techniques a navigator must master to control a ship under wind effects!
Ship underway with wind from right astern:
When the wind is blowing from the right astern, steering the ship becomes easy; however, in case of head wind, the stern part of the ship has the tendency to pay off on either sides. This is a difficult situation to tackle and getting the ship back on course is no piece of cake.
Such effect is more often seen on ships where the accommodation area is at the aft region. Moreover, the wind in such case has no braking effect.
Note: Given a choice between head wind & wind from right astern, the head wind is preferred for berthing.
Ship underway with wind from abeam:
When the ship is underway with the wind flowing from abeam, the steering of the ship is not affected. However, depending on the strength of the wind, the ship drifts sideways due to leeway and this has to be accounted for while handling the ship.
Ship underway with wind on the bow
Here again in lighter conditions, the effect on the ship’s stem is larger and this tends the ship’s head to swing away from the wind (leeward). This requires the weather helm (helm on the side of the wind) to be steered continuously.
Ship underway with wind on quarter:
When the wind is pushing the ship’s stern away to leeward, the stern tends to swing towards the leeward. The ship is therefore steered towards the wind and the ship is required to be given a lee helm.
Vessel under stern way:
When the ship is going astern, it rarely goes at a great speed. When going astern most ships also tend to swing to the starboard. The effect of the wind is therefore a little more complex.
In ballast condition where the wind catches the bow, which it often does, the stern is pulled into the wind. This effect is quite definite & rapid.
All ships turn around a pivoting point. This point is an imaginary reference and is fixed from observations of the ship turning around. It is known that when going astern the pivoting point moves aft.
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