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October 2012 www.sname.org/sname/mt e clipper era started to go into decline in 1869, when two key events took place. First, the transcontinental railroads made possible speedy and e cient overland con- nections between the American East Coast and California. Second, the opening of the Suez Canal made steam ship transit to the Far East from northern Europe faster and more reliable than sailing round Africa by way of the Cape of Good Hope. Lessons to Learn A study of our past can o er opportunities to better design our future. As Mark Twain wrote, History doesnt repeat itself, but sometimes it rhymes.? Clippers evolved ways to deal with two issues that remain important with todays o shore wind energy projects; namely, how to handle extracting maximum power over a wide range of wind speeds and how to main- tain the wind energy conversion devices at sea over time. While the methodologies evolved to deal with these issues, as described here, may not be directly applicable to offshore wind energy, a study of these approaches may stimulate ideas on new solutions. Harnessing maximum power Designers of clipper ships solved the rst prob- lem by developing variable sail area capability from ultra-light wind operations with skysails and studding sails set to hurricane conditions with all sails furled and sometimes spars low- ered or brought to deck, with in nite variability in between. A big clipper could set 80,000 sq. ft. of canvas in light airs. Both American and British clippers were rigged as three-masted ships; that is, square sails on fore, main, and mizzen masts. From the deck up, the sails were course, topsail, topgallant, royal and in some cases sky sails. It is interesting to note that British clip- pers typically had split topsails, that is, an upper topsail and a lower topsail, each with its own yard, while American clippers of similar size had a single topsail with multi- ple rows of ree ng points. e topsails were normally the most heavily used sails on the rig and were the last to be taken in as sail was reduced in heavy weather. The Flying Cloud was typical of American clippers. She reportedly crossed three skysail yards, had royal stunsails, a reef band in her topgallant sails, four reefs in her topsails, and swinging booms and passaree to spread her fore lower stunsail and haul out the clews of the foresail. As the foregoing indicates, it was not uncommon for American ships to set skysails above the royals on all three masts, while, if tted at all on British ships, skysails were usu- ally only on the main mast. e reasons for this di erence in American and British prac- tice remain obscure, but it may have been that the American ships often sailed in lighter winds on the U.S. east coast than the British ships did on the lee shore of the Atlantic. e split topsails allowed for easier sail handling and reduced the need to reef. At-sea maintenance e second problem of maintenance of the sails and rigging was addressed by careful design of the masting and rigging to minimize wear and by designing the components of the rig such that they could be easily replaced at sea by the onboard operating crew. Examination of the logs of famous clipper ships shows that repairs and maintenance of mast, spars, standing and running rigging, and sails was a continuous activity. Structural failure of components was not unknown, but more continuous was the wear and abrasion from constant motion at sea. A note from the log of the previously mentioned Flying Cloud shows how structural failure of masts and spars was routinely dealt with in the summer of 1851 by the crew of such ships: r + V O F - P T U N B J O U P Q T B J M Z B S E B O E N B J O and mizzen topgallant masts r + V O F 4 F O U V Q U P Q H B M M B O U N B T U T B O E Z B S E T r + V O F 4 F O U V Q N B J O U P Q T B J M Z B S E B O E T F U all possible sail r + V O F % J T D P W F S F E N B J O N B T U C B E M Z sprung about a foot from then hounds and shed it ese ships were designed to have their rigs repaired and replaced by their operat- ing crew, who were expert at doing so. The call of the sea In the last sentence of his classic book, e China Clippers , published in 1919, Basil Lubbock laments the passing of the clipper ship era: I bring to a nish with the sad thought that along with the China clipper there has departed not only that high art called seamanship, but also much of the romance, charm and virility of sea life.? The author of this article does not share these views. Today, more than ever, we have challenging careers in design- ing, building, and operating some of the most advanced and sophisticated ships and ocean structures ever conceived. But todays activities are built on strong links back to the clipper era, and beyond. ankfully, the call of the sea is still loud in many ears. MTPeter G. Noble is chief naval architect at ConocoPhillips. He served as an apprentice in the William Denny Bros. Leven Shipyard in Dumbarton, Scotland while obtaining his degree in naval architecture from the University of Glasgow. Dennys completed construction of the Cutty Sark in 1869 when the original shipbuilder, Scott and Linton, went into bankruptcy. More an 3,000 Years continued (historical note) Further Reading Learn more about the clipper ships by c hecking out the following resources: Cutler, Carl C., Greyhounds of the sea: The story of the American clipper ship (third edition, 1984). Crothers, William L., The American-built clipper ship, 1850?1856: characteristics, construction, and details (1997). Lubbock, Basil, The China clippers. The Century seafarers (1984).