Abstract
Recent research has demonstrated that extreme waves, waves with crest to trough heights of 20 to 30 meters, occur more frequently than previously thought. Also, over the past several decades, a surprising number of large commercial vessels have been lost in incidents involving extreme waves. Many of the victims were bulk carriers. Current design criteria generally consider significant wave heights less than 11 meters (36 feet). Based on what is known today, this criterion is inadequate and consideration should be given to designing for significant wave heights of 20 meters (65 feet), meanwhile recognizing that waves 30 meters (98 feet) high are not out of the question. The dynamic force of wave impacts should also be included in the structural analysis of the vessel, hatch covers and other vulnerable areas (as opposed to relying on static or quasi-dynamic analyses).
Introduction
Recent research by the European Community has demonstrated that extreme waves—waves with crest to trough heights of 20 to 30 meters—occur more frequently than previously thought (MaxWave Project, 2003). In addition, over the past several decades, a surprising number of large commercial vessels have been lost in incidents involving extreme waves. Many of the victims were bulk carriers that broke up so quickly that they sank before a distress message could be sent or the crew could be rescued.
There also have been a number of widely publicized events where passenger liners encountered large waves (20 meters or higher) that caused damage, injured passengers and crew members, but did not lead to loss of the vessel. This is not a new phenomenon; there are well-documented events dating back to at least the early 1940s.
These two facts, vessel losses combined with knowledge that waves larger than previously considered likely may be encountered, suggest that reviewing vessel design criteria may be necessary. (Smith, 2006).
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Some important context for why things turned so ugly after two months of peace, and why a false narrative took hold in such a coordinated way afterward, is that the CIA and its cutouts were openly present. For starters, 30 year CIA veteran James Lilley was appointed ambassador to China on April 20th, five days after the start of public gatherings in Tiananmen, which were initially to mourn the April 15 death of Hu Yaobang. Gene Sharp, who literally wrote the manual for how to start nonviolent color revolutions, flew in for 9 days and observed mysterious efforts to drive the protesters to violence — an intelligence asset only partially aware of the project he was involved in. The CIA was embedded with the protesters "for months" according to the Vancouver Sun, steering and equipping them. Voice of America was broadcasting disinformation to PLA military bases claiming some units were loyal to the protesters and were firing on other units, and claiming Deng Xiaoping was near death — literally attempting to whip up a military insurrection. This was a committed US effort to topple the Chinese government, using the momentum of the USSR dissolving and Hu Yaobang’s death.