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Old 12-19-2012, 12:16 PM   #81
Art
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Quote:
Originally Posted by Baker View Post


Now....I got one for y'all??? Does cross current affect your SOG at all??? On the circular slide rule, it says it does not. But I disagree.
Exact 90 degree (any degree less or more will also somewhat alter SOG results) cross current affects "straight line" SOG (point A to point B) in that you must tack an extent (length and duration of tack depends on cross current speed) to stay on course to reach point B from point A. This means you traveled a somewhat (a little bit) further in total "over land" distance. Therefore the comparison of SOG calculated if traveling on a straight line from A to B would be faster than equivalent "straight line" SOG from point A to B when tacking due to cross current. All comparisons are figuring no wind whatsoever.
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