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"Righting" redirects here. For the innate ability of a cat to orient itself as it falls in order to land on its feet, see cat righting reflex. Capsizing refers to when a boat or ship is tipped over until disabled. The act of reversing a capsized vessel is called righting.
If a capsized vessel has sufficient flotation to prevent sinking, it may recover on its own if the stability is such that it is not stable inverted. Vessels of this design are called self-righting.
Small dinghies frequently capsize in the normal course of use and can usually be recovered by the crew. Some types of dinghy are occasionally deliberately capsized, as righting the vessel again can be the fastest means of draining water from the boat.
In a storm, even large vessels may be rolled by being hit broadside by a large wave or "pitchpoled" stem over stern in extreme waves. This is normally catastrophic for larger ships, and smaller yachts can be dismasted (i.e., lose their masts and rigging) due to the drag as the boat is forced to roll over.
Among ship types, the RORO is more prone to capsize due to having large open car decks near to the waterline. The doors can fail, then the free surface effect can cause increasingly larger occillations leading to a capsize. Additionally, as the ship rolls, vehicles can break free and slide down adversely altering the centre of gravity and accelerating the roll and possibly turning an otherwise recoverable roll into a capsize.
A capsized kayak may be righted with a roll or eskimo rescue. As long as the kayaker knows how to react, the water is not too shallow, and the location is not close to dangers which would require evasive action by the kayaker - which cannot be taken while capsized - capsizing itself is usually not considered dangerous. In whitewater kayaking, capsizing occurs frequently and is accepted as an ordinary part of the sport; depending on personal experience, the difficulty of the water, and the preferred kayaking style (esp. playboating), many whitewater kayakers likely capsize several times each time they go kayaking.
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 maneuver. 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.
The capsize can result from extreme broaching, especially if the keel has insufficient leverage to tilt the vessel upright.
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 dinghys 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.
Notable capsizings
- Mary Rose, 19 July 1545, English carrack, 380 dead.
- SS Eastland, 1915, excursion boat, 845 dead, greatest loss of life on the Great Lakes.
- Szent István, 1918, Austro-Hungarian capital warship, torpedoed, 89 dead.
- USS Oklahoma, 7 December 1941, U.S. battleship torpedoed at Pearl Harbor, 415 missing or killed.
- SS Normandie, 9 February 1942, aka USS Lafayette, no casualties.
- Tirpitz, 12 November 1944, almost 1000 dead.
- Yamato, 7 April 1945, 2,475 dead.
- Andrea Doria, 25 July 1956, killing 46 passengers at the area of the Stockholm's impact.
- Herald of Free Enterprise, 6 March 1987, killing 193 passengers.
- Jan Heweliusz, 14 January 1993, leaving 54 people dead.
- Estonia, 28 September 1994, killing 852 passengers.
- La Joola, 26 September 2002, Senegalese ferry, at least 1,863 dead.
- M.V. Rocknes, 19 January 2004, Dutch rock discharge vessel, capsized south of Bergen, Norway, killing 18 of 30 crew.1
- MV Demas Victory, 30 June 2009, which sails to offshore oil and gas platforms capsized off the coast of Qatari capital city of Doha.2
See also
External links
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