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About BearDown185

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    C420, Optimist
  1. Thank you for the helpful feedback. It sounds like there is a dearth of solid numbers. As for tracking boat speed, these days various personal electronic devices (cameras, smartphones, watches) have GPS support and can track your speed and course during practices. I was looking for a rule of thumb to give to Club 420 sailors in various weight ranges as to when they should be feeling out a broad reach for planing conditions. As in "the forecast predicts the wind should reach a constant 12 kts around 11am, so don't forget to start feeling out the conditions after the 3rd race."
  2. See this. Dinghies with a relatively flat aft will begin to rise out of the water one they hit a certain boat speed. This results in a decrease in drag from the hull/water interaction, which results in a further increase in speed, which results in even more rise, which results in even less drag, which results in even more speed, until the boat is eventually riding across the top of the water. Once you hit this point, the boat's maximum speed is no longer limited by its natural hull speed as it is now skimming across the surface of the water and will take off like a rocket. The a
  3. With the caveat that it will necessarily depend on crew weight and wave conditions, is there a rough rule of thumb for when a C420 will start to plane when running or on a broad reach? Something like a 220lb crew needs X kt wind or XX mph boat speed; a 275lb crew needs Y kts/Z mph boat speed? People's subjective experience at given crew weights would also be very useful.
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