With regards to windage. We have an endeavour 48. She's high at the sides, so yes, there is windage. The engines being far apart ,though, give you a lot of manouverability. Personally I found that learning to dock in current was more of an issue than wind. Two other chaps who have 48's have put bow thrusters on and swear by them. With regards to ocean crossing, A big serious tennant design cat would be the way to go, or a sailboat. regards Jonah. www.jonah-art.com www.jonahs-whale.com

Wind and current effects make maneuvering interesting, and with practice, fun. Because water is more dense than air, the dynamic pressure that a moderate current exerts on a hull is much greater than that of a comparable breeze. On the other hand, we can sometimes find ourselves maneuvering in decidedly fresh winds. That's when it's useful to reflect on Bernoulli's Theorem, which Crenshaw's Naval Shiphandling cites to explain that the dynamic pressure of wind (or any other fluid) increases as the square of velocity. Put differently, when the wind picks up from ten to twenty knots, the force exerted on your hull does not merely double - it increases fourfold, if I understand Capt. Crenshaw and Monsieur Bernoulli correctly. It sure feels like that's so. In my former career, I ran a three- decked dinner and sightseeing boat with a water draft of six feet, and an air draft of over thirty feet, distributed along a hull length of 135 feet. Obviously, wind speed and direction were factors in every movement. While I won't deny that there were occasional thrills, it helps to remember that you can make the wind and current work for you as easily as against you. Just form a mental picture of where the outside forces are coming from, and use your propellers, boat speed, momentum, and rudder effect accordingly. E.g., try to approach anything from downwind, and let its force work as your air brake. Same applies with current. Jonah Jones mentions bow thrusters, and I can't refrain from throwing in my two cents worth on that subject, as well. Bow thrusters are like insurance companies, which is to say they are great, until the day comes (and it will) when you really need them. When the wind is cranking, or the current is running enough to make you wonder whether you even ought to be trying to dock or get underway, you'd better be prepared to handle your boat with its main engines and rudders. Use spring lines to kick one end of the vessel around and get it aimed in your intended direction of travel, and then go. The power of most thrusters is adequate for moderate conditions, but if you install a large enough thruster for those truly hairy moments, you'll have two big holes in your boat beneath the waterline, a suite of heavy machinery to power it, and still no guarantee that it'll preserve your dignity. To depend on a bow thruster is to invite trouble on board. Trouble sneaks on easily and often enough without any engraved invitations. Alan Bliss On Apr 22, 2009, at 3:37 PM, Jonah Jones wrote: > With regards to windage. > We have an endeavour 48. > She's high at the sides, so yes, there is windage. > The engines being far apart ,though, give you a lot of > manouverability. > Personally I found that learning to dock in current was more of an > issue than wind. > > Two other chaps who have 48's have put bow thrusters on and swear by > them. > > With regards to ocean crossing, > A big serious tennant design cat would be the way to go, or a > sailboat. > > regards Jonah. > > > www.jonah-art.com > www.jonahs-whale.com > _______________________________________________ > Power-Catamaran Mailing List