Weather

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Weathering refers to strategic and tactical measures as well as behavior in order to avoid damage and dangers to a sea vehicle as well as its cargo and crew in a storm and / or in heavy seas . Priority is given to measures to avert danger to life and limb. Weathering also refers to the decision of the ship's command not to call at a port during a storm or to leave the port for the duration of the storm in order to avoid the special dangers in shallow coastal water ( e.g. ground sea , breakers, tidal currents ). The storm is then weathered in deep water and the port is called when the weather improves.

Strategically

The most strategically effective measure is to avoid a bad weather area by avoiding a vehicle in port and a vehicle at sea bypassing the bad weather area. Modern meteorological services - for example the ship route advice from the German Weather Service (DWD) - make it possible to be informed about the current weather dangers at an early stage. While a skipper one more day to spend in the port may easily to weather there must of captain in the merchant shipping always find a compromise between risks and route settings.

If there is no possibility or no desire to bypass a bad weather area, a whole series of measures must be carried out in good time to prepare the ship for heavy seas and strong winds: Checking and, if necessary, reinforcing the lashing that secures the cargo, the watertight closing of hatches and portholes, stowing and securing objects, on sailing ships the precautionary reefing and preparation of storm sails , attaching safety lines and special briefing of the crew if they are inexperienced.

Tactical

The respective storm tactic depends heavily on the type of boat. In most cases it is advisable to avoid a course across the waves. In sailing boats, the most common storm tactics are:

  • Enclosed, possibly with the help of the machine
    When enclosed , the rudder is lashed to windward and left to its own devices. The boat drifts leeward almost parallel to the waves . Enclosing is only possible as long as the boat can still carry sails.
  • active sailing under storm sails
    On light yachts it is advisable to sail actively for as long as possible under storm sails. The boat should take a close -hauled course in order to cross the waves with the bow first. However, if the boat does not get over the wave and drift astern or stuck with its bow in the front of a wave, there is a risk of capsizing.
  • Piling in front of top and rigging, possibly with towed lines
    When pumping in front of the top and rigging, the boat runs down without any sails before the storm. This is necessary when the storm has reached a strength at which no sails can be guided. The wind pressure on the mast is sufficient for the yacht to reach astonishingly high speeds and to remain steerable (a ship has to make its way through the water in order to remain steerable). The danger here is that the boat will cross-cut and capsize when a wave is running . By dragging lines or a sea anchor , some speed can be taken out of the boat to minimize the danger. It also keeps the stern in the wind.
  • Lying at sea anchor
    When lying at sea ​​anchor , the bow of the ship is kept in the wind. The advantage over bilging in front of the top and rigging is that the bow offers more protection against waves. However, the tactic requires good preparation and equipment designed for it.

Bending, bilging in front of the top and rigging as well as lying in front of sea anchors in front of Legerwall , i.e. in front of a coast with an onshore wind, are problematic , as there is then the risk that the ship will be pushed against the coast and leak . Even if the depth offshore would allow the anchor to be deployed, it would be difficult to position it in a storm so that it would hold. Even if this were to succeed, the strong pulling forces of the ship on the anchor chain would damage the ship or tear the chain.

The machine is only of limited help in a storm, as many motors on sailing ships are not equipped with enough power to be able to start properly against wind and high waves. In addition, there is not necessarily enough fuel available to keep the machine working at high performance for days. If the engine runs continuously with a steep heel , it could also be damaged because the oil lubrication is no longer guaranteed.

The following tactics are available in commercial shipping:

  • Head against the sea with minimal travel
    First of all, the speed has to be reduced so that the ship lies well without using hard, but remains steerable. Then the ship should be turned quickly at a favorable moment in order to reach the desired position and thus the speed is again reduced to a controllable minimum. If the length of the ship is the same as the wavelength, strength problems can arise. This procedure is used for stability problems, for necessary work on deck or for difficult cargo. Caution is advised in the case of engine problems (high load) and on ships with a protruding stem and / or little freeboard.

literature

Individual evidence

  1. ↑ Accident investigation report by the BSU, capsizing of the "TAUBE" on January 20, 2009
  2. ^ Accident investigation report of the BSU, accident of the "CMS CHICAGO EXPRESS" on September 24, 2008
  3. ↑ Knud Benedict , Christoph Wand : Handbuch Nautik II Seehafen Verlag , Hamburg 2011, ISBN 978-3-87743-826-8 , pages 466f.