BAD WEATHER MANEUVERS

Head to sea, or wind and sea on fine bow, at reduced speed:

	Most suitable for deep draft vessels.
	Leeward drift is minimized (vessel is liable to sustain considerable pounding).
	Weather is allowed to pass over the vessel.
	The speed is considerably reduced.
	It affects the period of encounter of the oncoming wave formation and subsequently reduces pounding.
	Course and speed to be altered to remove possibility of hogging, sagging and synchronism.
	Situation becomes uncomfortable when violent pitching results in ‘racing propellers’, puts excessive stress on engines.
	Absolute control of rudder power is essential.
	Power should be reduced to minimum necessary to maintain steerage way and avoid undue stress on machinery.
	Two steering motors to be operational.
	Critical rpm to be avoided.

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Stern to sea, at reduced speed, running before the wind:

	When bad weather overtakes vessel, she will find herself running before the wind.
	Preferable to take a course with wind on the quarter rather than stern, which may cause ‘pooping’.
	Vessel will not move as violently as a vessel head to sea.
	Speed adjustment together with long period of encounter will probably reduce wave impact without any great delay.
	A distinct danger with stern to sea is when the vessel required to turn across the wave front is ‘broach to’.

Heaving to, preferably on the lee of an island:

	Necessary when due to the stress of the weather the voyage is required to be temporarily discontinued.
	The vessel is maneuvered so as to ride the sea in the most favorable position.
	Problems may be encountered associated with crew fatigue or damage to cargo for a lengthy period of time.
	Most effective when taken advantage of a lee of an island or land mass.
	Action will depend on the type and form of the vessel.
	A reduction of speed will probably be the earliest action to reduce motion of the vessel and avoid cargo shift.
	Power not to be reduced to an extent of stalling the main engine or revolutions are critical.
	If it is decided to stop the vessel, sufficient sea room should be available.
	Heavy rolling can be expected.
	There is risk of synchronism and cargo shift.
	Vessel needs to have a good water tight integrity and adequate GM.

Anchoring in shallow waters:

	Used when the vessel in shallow water.
	Employed to prevent blown down to a lee shore.
	Two anchors may be used.
	Engines can be used to reduce stress on the cable.
	Anchor will reduce the rate of drift.
	If grounding is not prevented, refloating may be assisted by heaving on the cables.

Altering course to avoid bad weather:

	To be used before encountering bad weather.
	Take an alternative route to destination.
	Take evasive actions to be away from bad weather.
	Likely to result in more distance.
	If alteration is not well planned or substantial, bad weather may suddenly change direction and vessel may be caught into it.

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Updated: September 17, 2007