British Cruise Line: Passenger Killed After 'Freak Wave' Hits Ship
The British Owned MARCO POLO (Photo:Luca Riva, GNU Free Documentation License.
"(CNN) -- A passenger aboard the British-based cruise ship MS Marco Polo was killed after the ship was hit by a "freak wave during adverse sea conditions" as it made its way into the English Channel, according to a statement released Friday by the ship's owner, Cruise & Maritime Voyages." Complete Story
OPPORTUNITY FOR A CASE STUDYNOW IMAGINE THAT YOU ARE THE PERSONAL INJURY ATTORNEY FOR THE DECEASED FAMILY OR THE INSURANCE DEFENSE LAWYER FOR THE SHIP OPERATING COMPANY. HOW DO YOU ANALYZE THE ACTUAL CIRCUMSTANCES RELATIVE TO THE "FREAK WAVE CLAIM".WAS IT REALLY A FREAK WAVE, OR NEGLIGENT SHIP HANDLING AND NAVIGATION. TO COMPREHEND THE HEART OF THAT ISSUE YOU MUST BE ABLE TO DEFINE A TRULY "FREAK WAVE" AND MEASURE WHAT ACTUALLY HAPPENED AGAINST THAT. THIS IS WHERE THE AMERICAN ADMIRALTY BUREAU'S COMMENTATORS WHICH WE ARE PUBLISHING FOR FREE USE IN OUR AUTHORITATIVE LITERATURE SECTION COME IN. BELOW WE REPRINT THE APPROPRIATE "COMMENT" FROM VOL.3. THERE ARE LESSONS HERE NOT ONLY FOR LAWYERS BUT ALSO FOR MASTERS , MATES, AND PILOTS.
CITE AS: AAB COM. NO.1, VOL. 3 (1966/UPDATED 2013) ISBN 1-87977859-9
FREAK WAVE THEORY A "Freak Wave"may be defined as a wave out of proportion to the observable sea state of such magnitude that an ordinarily trained and prudent mariner would not anticipate its presence in the sea state. The "freak wave " is often invoked in personal injury cases involving fast moving boats in a relatively heavy sea state,as a defense against charges of excessive speed. In actuality most such "freak waves" are not freak at all and should have been anticipated. Let's examine an actual alleged `"freak wave" from Admiralty Bureau case records.
Here is a description of the sea state from our record:
"The weather report by (name withheld to protect client confidentiality) indicated a moderate Northeast wind flow for the blocks examined all day. North Northeast winds prevailed the day before 10/25/1993. The official observed sea states from Vermilion Block 265 located approximately 5 miles from block 267 indicated seas of 5 to 7 feet at 2258 CST on 10/24/1993 and 5 to 7 feet to 4 to 6 feet throughout 10/25/1993. The boat log indicated seas of 6 to 8 feet. The comparison of the official readings from an adjacent block with the boat log's record indicates a one foot difference in observed sea height. This difference could be accounted by the distance between the recording stations or differences in the height of the eye and experience of the different observers. Winds observed in block 265 varied between 24 to 26.5 knots. It is not known if the boat observer had an anemometer or the ability to correct apparent wind to compute wind speed and direction. Allowing for such differences it appears the closest official weather observations and the logged boat observations are sufficiently close to indicate that the areas had quite similar weather with winds in the 22 to 27 knot range.
Here is our initial analysis:
The Beaufort scale describes such winds as a "strong breeze" and assigns them the description of "Beaufort no.6". The Beaufort Scale predicts the following descriptive sea state for a no. 6 sea: ''Large waves begin to form: the white foam crests are more extensive (Probably some spray)".
The Beaufort Scale indicates that at 22 knots the average wave height will be 6.4 feet while approximately 1/10 of the waves will reach 10 feet and one tenth will be significantly below the average.
Thus, in a Beaufort Force 6 sea state, a mariner should expect at least more than a 3.6 foot difference between wave heights for at least 10% of the waves encountered. However, at the coincidence of the lowest average wave height and the highest , the difference will be much greater. Finally it should be noted that the Beaufort scale actually utilizes the highest one third of observed waves for average height.The actual variance of wave heights in a given sea state is best illustrated with this quote from "WEATHER FOR THE MARINER" by William J. Kotsch published by the Naval Institute Press.
"By using table 11-8, it is seen , for example, that if a train has a significant wave height of 10 feet, the highest wave is 18.7 feet, the average highest 10 percent is 12.9 feet, and the mean wave height is 6.4 feet. "
In the example above, the highest wave in the sea state and some waves of even greater difference are predicted..
The Beaufort scale is a common feature in much of the authoritative literature utilized by the Coast Guard's National Maritime Center to construct professional mariner license examinations. All licensed professional mariners are , or should be, familiar with their professional literature and some originally intended for amateur boatman, such as Chapman's "PILOTING SEAMANSHIP AND SMALL BOAT HANDLING".
OUR CONCLUSION: A "freak wave" can not include a wave height difference that can be accounted for by the ordinarily jumbled state of any sea as documented in the Beaufort scale. This wave height difference is often quite steep but should not be a surprise to the properly trained and ordinarily prudent mariner who should expect just such differences and adjust speed accordingly. The mariner should not run at a speed that accounts for only the "typical" or "average" wave height that he is looking at when he sets his speed . He must expect and plan for the ordinary jumbled sea state. Real "freak waves"are the product of more than prevailing wind. They are often the result of geological forces such as earth quakes and submarine volcanic activity. Recent satellite imagery studies have indicated that on any given day there are a few of these truly freak waves moving about the world's oceans mostly off of what we consider the busy shipping routes. While the "freak wave" or "monster wave" may be a daily phenomena on the world's oceans they generally occur thousands if not tens of thousands of miles apart, and are very small in number in the vastness of the world's oceans on any given day. Actual ship or boat encounters with these truly "freak" waves are exceedingly rare. Most litigated cases involving the "freak wave defense" against charges of unsafe speed actually involve wave height differences predicted by the Beaufort scale. The Beaufort Scale is studied by every class of U.S. licensed deck officer and is an expected element in their occupational licensing testing. Choosing a speed that doesn't consider the wave height differences described in the Beaufort Scale is simply imprudent seamanship. |
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