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Capsizing

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File:NormandieNY.jpg
SS Normandie, capsized in New York's harbor. (1942)

The common definition for capsized refers to when a boat or ship is tipped over until inverted. The act of reversing a capsized vessel is called righting.

If a capsized vessel has sufficient floatation to prevent sinking, it may recover on its own ('self-righting') if the stability is such that it is not stable inverted. Small dinghies often capsize in the normal course of use and can normally be recovered by the crew. Some types of dingy are occasionally deliberately capsized as it can be the fastest means of draining water from the boat.

In a storm, even a large vessel may be rolled by being hit broadside by a large wave or pitchpoled stem over stern in extreme waves. This is normally catastrophic leading to dismasting due to the drag on the rigging as the boat rolls (in a yacht), through to outright sinking and massive loss of life in a ship. Among ship types, the RORO is more prone to capsize due to a design feature of that class of ferry: large open car decks near to the water line.

To Prevent a Capsize and Precautions to Take in a Dingy or Small Yacht

  • Head into the wind.
  • Release the sheets.
  • Be sure the centerboard is lowered all the way.
  • Lower the sails.
  • Secure the boom, haul mainsheet tight, haul jib sheets tight and cleat them.
  • Secure all gear.
  • If in shallow water consider anchoring. Do not attempt to anchor if you can not make the anchor hold.
  • Sit on floorboards.
  • Put on life jackets.
  • Keep an eye on the weather.
  • Locate nearby boats for help if needed.

[1]

In Competition

A team at the 2005 ISAF Team Racing World Championship narrowly avoids capsizing.

In competitive yacht racing, a capsized boat has certain special rights as it cannot manouvre. A boat is deemed capsized when the mast is touching the water; when it is fully inverted, it is said to have turned turtle or turtled. Good racers can often recover from a capsize with minimal loss of time.

A capsized kayak may be righted with an roll or eskimo rescue.

Motor life boats are designed to be self righting if capsized but most other motorboats are not.

Training

The intermediate sailor is encouraged to capsize their dinghy in a safe location with supervision at least once to become acquainted with their boat's floating properties and the capsize process. The boat should then be righted, bailed out, and the sails reset, so that in the event of an uncontrolled capsize, the boat and its occupants are familiar with the procedure and may self recover.

Most small monohull sailboats can be normally be righted by standing or pulling down on the centerboard or daggerboard to lift the mast clear of the water. Depending on the design of the hull, the boat's righting moment will normally take effect once the mast is around 30 degrees from horizontal and help pull the boat vertical. Righting a Catamaran that is lying on its side involves using a righting line fed over the upper hull. The crew stands on the lower hull and pulls back on the righting line. In dingys such as the Hobie 16 it is imperative that at least one crew member assumes this task as soon as possible as there is a chance that the boat will turtle and then is extremely difficult to recover without assistance. In both cases, having a crew member lift the end of the mast out of the water may help speed the process, as the greatest challenge of righting a capsized boat is shedding the weight of the water from the sails. The bow of the capsized vessel should be pointed towards the wind so as when the sail starts to lift out of the water the wind can catch underneath the sail and help right the boat. Care should be taken not to let the boat swing all the way over and capsize on the other side, frequently with the crew on the bottom.

You must be careful doing this because it is possible for the boat to swing re-capsize to leeward, or with the mast pointing away from the wind. The best procedure for righting a boat can be found by practicing the righting procedure.

Famous capsizes

References

George, M. B. Basic Sailing. New York: The Hearst Coporation, 1971. 82-89.

  1. ^ George, M. B. Basic Sailing. New York: The Hearst Corporation, 1971. 82-89.