A UNIQUE VESSEL. AN UNPREDICTABLE JOURNEY.

May 26th, 2010, posted by Shore Crew Tags: Build, Islands, Plastiki, Plastiki daily update, Sailing

The Samoan Islands are to be the next stop for the Plastiki’s crew of six. The islands are some 1,300km away from where the crew originally intended to stop, Fiji.

The Plastiki is a down-wind boat which can make future movements a little hard to predict, hence this last minute change in plans. She can also be tricky to manoeuvre as our Safety Manager, Josh Hall, explains:

“She is designed as a down-wind craft and, indeed, cannot sail very close to the wind as normal sailing craft can. The bottles which surround her two hulls also create a great deal of drag with the turbulence of the water that occurs around them, so her speeds are not high. Ideal conditions for The Plastiki are 20 knots winds from behind, as when the wind is lighter than 10 knots the drag from the bottles has more effect. Equally, the drag means that The Plastiki is a difficult boat to manoeuvre as she slows even more through a tack or gybe – in fact gybing (putting the stern of the boat through the eye of the wind) is the only effective way to put the wind in the other side of the sails when that is required.”

Another challenge the crew face when bringing the Plastiki into land is the boat’s tendency to ‘crab’ sideways which is largely because she doesn’t have a keel or side-board which limits the amount of sideways drift that occurs. Josh told us that the Plastiki’s unusual nature also means that: “The Plastiki crew must always be looking to keep her in following winds and need to avoid excessively strong winds and seas. Vigilance with the weather is key to them. They also must have a keen eye on the boat’s structure, regularly inspecting the structure for any signs that this very avante-garde material is not supporting the dynamics of sailing offshore.”

The Plastiki really is a unique, one-of-a-kind vessel, so whenever the crew encounters a new situation it really is a “learn as you go” type experience. As Josh reminds us: “The Plastiki is completely made of recyclable products – the hull and structure are made from recycled plastic bottles; the masts are ex-irrigation piping and the rigging is stainless steel that can be recycled. If so desired, the entire vessel could be recycled after the expedition – that is totally unique.”

For the sailing or boat enthusiasts out there, Josh also gives us a rundown on the boat’s sails which are what the boat relies upon to catch those trade winds and push them towards Sydney:

“On the forward mast (main mast), they can set a number of sails. At the front, going from the masthead to each bow are two permanently in place roller sails that they roll in or out as required. When the wind is blowing quite strongly from behind, they can go goosewing with these sails (one out on each side of the boat) to trap as much wind as possible. When the wind is lighter from behind, they can set a large spinnaker instead of using the roller sails. Also on the main mast is the mainsail, which is a sail that is nearly always up regardless of the wind direction. As the wind increases, they can reduce the size of the mainsail by taking in a reef where the sail is lowered somewhat and secured to the boom. The mainsail has 3 reefs in it for various wind strengths.”

When on land, the crew will be busy making rigorous checks of the complete vessel before setting out on the final sections of the expedition. “In these final sections the weather will be stronger and more volatile with the influences of low pressure areas gradually becoming more dominant,” warns Josh. “Therefore, numerous optimisations are being made to the sails and the rigging based on what has been learned about the vessel so far. Sails are being strengthened and various parts of the rigging which support the masts are being changed for a lighter material which will provide equal support for less weight aloft. Some daggerboards are also being fabricated locally that once fitted will help to stop the vessel “crabbing” or going sideways so much and this will greatly help with more accurate course keeping.”

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  1. Don Matheson says:

    Just discovered you guys. Bravo! I’m a former amateur sailor; presently a builder in East Hampton,New York. Sharing your concern for our world, I’m building a house which aspires to net-zero energy use. You folks have inspired me this morning, and I have thoroughly enjoyed reading your reports. Safe sailing, and thank you for your efforts to do something very important! Folks like you are the catalysts for change. Don