Sunday, June 7, 2020

Was Polynesia Settled from South America – Part VI

Continuing from the previous post regarding the settlement of Polynesia, the first five points were covered and we begin this article with #13 below:
13. “Sailing against the wind – this was the initial search-and-return voyage, to find out whether there were islands on the exposed side of the home island.”
Response: First of all, we need to understand the type of vessel that was used by these islanders—called an outrigger canoe—and how it was configured—with one or more lateral support floats called outriggers which were fastened to one or both sides of the main hull. Such outriggers were originally developed by the Austronesian speaking peoples of the islands of Southeast Asia for sea travel.
    They were used for fishing and transport from island to island. Even today, such people continue to be the primary users of the outrigger boats. Anciently they were carved from native koa trees, though the larger canoes were made from Oregon pine, which occasionally showed up as driftwood.
    These outriggers began in Southeast Asia—Brunei, Indonesia, Malaysia, Philippines, Singapore and east Timor, and included by some to include Western and Papua New Guinea. The Solomon Islands, of course, are just to the east of the Guineas, and situated within the group of islands found in the notoriously unpredictable seas of the Solomons. While voyages of over fifty miles are admittedly rare nowadays, yet the sudden rain squall blotting out all landmarks and giving rise to a very choppy sea makes one realize that the Melanesians of old must have been a stout-hearted race to even attempt the open seas between their own numerous islands.
    Stretching across eleven thousand square miles, the area features nearly one thousand islands in which inter-island movement was possible and constant. This area boasts some of the richest marine, flora and fauna biodiversity on Earth. The early inhabitants spent much of their time fishing in the plentiful waters in their outrigger canoes.
Top: An ancient outrigger canoe in Southeast Asia; Bottom: A modern outrigger canoe in the same islands 

Secondly, as for “sailing against the wind,” it should be understood that ships could never sail “against the wind.” What they could do was beat forward, or “tack,” enabling them to move without the wind at their back. To do this, they had to set a course to the right or to the left of the wind, and tack or turn back and forth across that course, which would bring the prow into the wind only for the short time the vessel changed from a starboard tack (course) to a port tack(course), which would only occur momentarily.
    To do this, the sail(s) had to be connected to moveable spars, which eventually showed up on outriggers with somewhat vertical spars. Thus, “sailing into the wind” is a sailing term, though misleading, since the vessel never sails directly into or against the wind.
    The other alternative would be to have the outrigger canoe moved by paddling, which was the common motive power for outriggers. However the great distances involved according to scientists would preclude such effort since we are talking about covering hundreds and even thousands of miles without seeing any kind of land.
    In addition, in an outrigger the sail always had to be to the leeward side of the mast. It was also important to keep the sail to windward of the hull when sailing, for if it was to leeward, the weight of the wind could force it under the water and a capsize the boat.
    It is also interesting that, though scientists claim these island-hopping seamen originated in the Solomon Islands, each cluster of islands had their own unique sail design, length, shape, and effectiveness—certainly not what would be expected to exist if these voyagers were from common backgrounds and locations. 
    This is also true of the various masts, since design and inclination varied from island group to island group—as an example, some groups had a vertical mast, others inclined their masts toward the prow and others toward the stern. It is also notable that those small island groups separated by great distances from other islands, had very unique designs, some of which had two masts, others had large double canoes, others had less sturdy designs and workmanship and others were manned by poor seamen (Howard M. Ballou, Ed, The Mid-Pacific Magazine, Vol.VIII, No.1, Honolulu, Hawaii, July 1914).
    As a matter of fact, it is far more realistic to think in terms of these islands to the east of the Solomons were quite different and bore little resemblance to those in the far west—making it hard to imagine that a single group of people spread out across the South Pacific from Taiwan or Indonesia eastward.
An early photo of the Moro of the Philippines and their double out-rigger canoes—note there are no masts or sails 

Early outriggers did not have sails—they came much later. However, there is the question of how close they could have sailed to the wind, and then there's the question of how close they would want to sail to the true wind. The two are quite different! There's a fundamental reason why boats go upwind at near 45º, and that's to maximize their velocity-made-good to windward. There is even some discussion that the angle might be close to 35º. In a conventional monohull sailboat. If you try to sail above that angle, your drag vector of the hull and sails exceeds the generated thrust of the sail(s), and you stall and stop.
    It is also claimed that a modern 12-metre can sail at 35 degrees to the true wind, which implies that it can tack through not the usual 90 degrees, but through some 70 degrees.
    Today, the replacement for them in the America's Cup are the ACC boats, larger and lighter than the 12s and with more sail. These boats are generally tacking though less than 70 degrees and probably average something like 65 degrees. That's 32.5 degrees to the wind on each tack and probably closer on one tack than the other due to wave conditions. This is very evident when watching them match race on the computer tracking during the Cup matches. On the other hand, a moderate performance boat like the AC class will point well above 45 degrees because while they can sail to a comparatively small apparent wind angle, they can't actually go fast and so must opt for a high angle.
    Thus, a high performance craft will sail at comparable apparent wind angles, but will opt for a lower course. The extra speed will more than make up for the extra distance sailed. So you won't actually see these boats tacking through less than 90 degrees.
    Theory says if the boat has very high performance, such that the speed can increase freely to the point that the boat sails at the same apparent wind angle all the time, the optimum course to windward is 45 degrees plus half the apparent wind angle. Very few craft can come close to this ideal and must sail higher and slower. But you can see that 45 degrees is a fundamental number and not a coincidence.
    However, it seems that the early mariners of the South Pacific, even in their incredible small sailing canoes, could do any better than that.
A sailing craft is said to be sailing close-hauled (beating or working to windward) when its sails are trimmed in tightly, are acting substantially like a wing, and the craft's course is as close to the wind as allows the sail(s) to generate lift

Sailing vessels cannot sail directly into the wind; a modern sailboat can get within about 45 degrees of the wind. However, a square rigged ship could barely sail into the wind at all, maybe no closer than 70-80 degrees. If you're sailing and you turn closer to the wind than you can sail, the sails start flapping (luffing), you slow down, stop, and eventually start drifting backwards. Thus, it was necessary anciently to have the wind at your back to sail effectively, with the most efficient condition to be running downwind with the wind directly behind the vessel.
    Certainly their voyages eastward against wind and currents were short when compared with the vastness of the Polynesians who sailed westward with the wind and currents. In fact, the winds and currents not only altered their destinations, but rough seas and storms blew a number off course and sent lost canoes to islands from which the seamen never returned.
(See the next post, “Polynesia Settled from South America – Part VII,” for more on the lack of reasoning behind claiming that early man island-hopped across the Pacific from west to east)

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