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#1
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That's right folks!
Think of a pickup truck driving along with the tailgate up compared to one with the tailgate down. The tailgate down goes faster and gets better mileage. It has less wind resistance. Now look at the Beneteau 35s5 stern. Obviously, it has less resistance. But there's more! MORE! Because the airflow is more laminar through the cockpit, there's flow separation at the stern and the laminar airflow beneath the boom increases the pressure differential on opposite sides of the sail surface, which increases efficiency! Especially when sailing into the wind! The swim platform cockpit allows the 35s5 to sail closer to the wind! It will also sail faster! Sounds improbable? Well then, just stand a sheet of plywood at the stern and watch what happens. The boat slows and doesn't point as well! It also means enhanced light air performance! All scientifically proven! And measured!!! Amen! |
#2
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![]() "Bob Crantz" wrote in message ink.net... That's right folks! Think of a pickup truck driving along with the tailgate up compared to one with the tailgate down. The tailgate down goes faster and gets better mileage. It has less wind resistance. Now look at the Beneteau 35s5 stern. Obviously, it has less resistance. But there's more! MORE! Because the airflow is more laminar through the cockpit, there's flow separation at the stern and the laminar airflow beneath the boom increases the pressure differential on opposite sides of the sail surface, which increases efficiency! Especially when sailing into the wind! The swim platform cockpit allows the 35s5 to sail closer to the wind! It will also sail faster! Sounds improbable? Well then, just stand a sheet of plywood at the stern and watch what happens. The boat slows and doesn't point as well! It also means enhanced light air performance! All scientifically proven! And measured!!! Amen! Good in theory, but in practice, bubbles IS the sheet of plywood standing at the stern, excepting of course, he's much heavier, more like 30 sheets of plywood. Repent! John Cairns |
#3
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I remember reading that Beneteau for the 35s5 copied the platform from
the Colgate 26 which on that boat is where the instructor stands. Beneteau felt that the people who buy their boats need instructors. |
#4
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Bob Crantz wrote:
That's right folks! Think of a pickup truck driving along with the tailgate up compared to one with the tailgate down. The tailgate down goes faster and gets better mileage. It has less wind resistance. Now look at the Beneteau 35s5 stern. Obviously, it has less resistance. But there's more! MORE! Because the airflow is more laminar through the cockpit, there's flow separation at the stern and the laminar airflow beneath the boom increases the pressure differential on opposite sides of the sail surface, which increases efficiency! Especially when sailing into the wind! The swim platform cockpit allows the 35s5 to sail closer to the wind! It will also sail faster! Sounds improbable? Well then, just stand a sheet of plywood at the stern and watch what happens. The boat slows and doesn't point as well! It also means enhanced light air performance! All scientifically proven! And measured!!! Amen! No wonder he is a salesman. |
#5
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Actually you're an idiot. The TV show MythBusters has recently proven,
quite conclusively IMHO, that the pickup with the gate up is actually far more fuel efficient than one with the liftgate down. The liftgate being up causes a "bubble" of air to force the airflow to stay separated from the truck, where the lowered liftgate causes the airflow to become much more turbulent, and causes drag. Besides, most sailboats have so much crap interuppting the airflow, that the lack or existence of a swim platform is probably quite negligible in terms of drag. The shape of the mast, whether it rotates, whether you have a bimini or dodger, the shape of the cabinroof, are probably all much more influential on the drag of a boat, as is the shape of the hull, keel, rudder, in terms of in-water drag. Lastly, I would like to mention that water drag has far greater effect on a boat than does air drag. Besides, a sailboat, with a pretty bloody big kite like sail up, isn't going to win any aerodynamic design awards. On 2005-12-22 21:25:34 -0500, "Bob Crantz" said: That's right folks! Think of a pickup truck driving along with the tailgate up compared to one with the tailgate down. The tailgate down goes faster and gets better mileage. It has less wind resistance. Now look at the Beneteau 35s5 stern. Obviously, it has less resistance. But there's more! MORE! Because the airflow is more laminar through the cockpit, there's flow separation at the stern and the laminar airflow beneath the boom increases the pressure differential on opposite sides of the sail surface, which increases efficiency! Especially when sailing into the wind! The swim platform cockpit allows the 35s5 to sail closer to the wind! It will also sail faster! Sounds improbable? Well then, just stand a sheet of plywood at the stern and watch what happens. The boat slows and doesn't point as well! It also means enhanced light air performance! All scientifically proven! And measured!!! Amen! |
#6
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![]() "Bob Crantz" wrote in message ink.net... That's right folks! Think of a pickup truck driving along with the tailgate up compared to one with the tailgate down. Actually on Mythbusters the proved that the tail gate up was more efficient!!!!! Sorry JB The tailgate down goes faster and gets better mileage. It has less wind resistance. Now look at the Beneteau 35s5 stern. Obviously, it has less resistance. But there's more! MORE! Because the airflow is more laminar through the cockpit, there's flow separation at the stern and the laminar airflow beneath the boom increases the pressure differential on opposite sides of the sail surface, which increases efficiency! Especially when sailing into the wind! The swim platform cockpit allows the 35s5 to sail closer to the wind! It will also sail faster! Sounds improbable? Well then, just stand a sheet of plywood at the stern and watch what happens. The boat slows and doesn't point as well! It also means enhanced light air performance! All scientifically proven! And measured!!! Amen! |
#7
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"Bob Crantz" wrote
Think of a pickup truck driving along with the tailgate up compared to one with the tailgate down. J Beck wrote: Actually on Mythbusters the proved that the tail gate up was more efficient!!!!! Sorry Discussed on Car Talk also.... DSK |
#8
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I beg to differ on who is the idiot. Myth busters tested on two different
trucks, same model. Did they test each with tailgate up and down? No. Did they do a significant sampling to get data? No. Their underwater testing using a scale model truck to draw conclusions violates Mach's principle of scaling. If the truck model is scaled by x, then the resultant viscosity and Reynold number of the fluid must also be scaled. They scaled it in the wrong direction by orders of magnitude. Would you draw aerodynamic conclusions about a F-14 fighter by using an HO scale model in a tank of 90W motor oil? So what did they prove? That viewers are not astute enough to know what proof is. Here's measurements that show otherwise: http://www.linear-logic.com/tailgate.htm Shows almost no difference http://www.popularmechanics.com/auto...tml?page=5&c=y Shows almost no difference in short beds, but a difference in long beds Now the question remains: Is there no airflow in the cockpit of a 35s5? You are right about cabin roof, see my other thread. Amen! 35s5 performance can't be refuted! "dog" wrote in message news:2005122300004616807-dog@nomailcom... Actually you're an idiot. The TV show MythBusters has recently proven, quite conclusively IMHO, that the pickup with the gate up is actually far more fuel efficient than one with the liftgate down. The liftgate being up causes a "bubble" of air to force the airflow to stay separated from the truck, where the lowered liftgate causes the airflow to become much more turbulent, and causes drag. Besides, most sailboats have so much crap interuppting the airflow, that the lack or existence of a swim platform is probably quite negligible in terms of drag. The shape of the mast, whether it rotates, whether you have a bimini or dodger, the shape of the cabinroof, are probably all much more influential on the drag of a boat, as is the shape of the hull, keel, rudder, in terms of in-water drag. Lastly, I would like to mention that water drag has far greater effect on a boat than does air drag. Besides, a sailboat, with a pretty bloody big kite like sail up, isn't going to win any aerodynamic design awards. On 2005-12-22 21:25:34 -0500, "Bob Crantz" said: That's right folks! Think of a pickup truck driving along with the tailgate up compared to one with the tailgate down. The tailgate down goes faster and gets better mileage. It has less wind resistance. Now look at the Beneteau 35s5 stern. Obviously, it has less resistance. But there's more! MORE! Because the airflow is more laminar through the cockpit, there's flow separation at the stern and the laminar airflow beneath the boom increases the pressure differential on opposite sides of the sail surface, which increases efficiency! Especially when sailing into the wind! The swim platform cockpit allows the 35s5 to sail closer to the wind! It will also sail faster! Sounds improbable? Well then, just stand a sheet of plywood at the stern and watch what happens. The boat slows and doesn't point as well! It also means enhanced light air performance! All scientifically proven! And measured!!! Amen! |
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