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Old 02-29-2012
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CalebD CalebD is offline
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OK then dog bone David, you said your GPS "log show speeds of 6,7 and 8 knots" on your way to "8A". That should be the first clue.
The theoretical hull speed of a Catalina 25' with only the jib up in winds around 20 kts. is what? About 4 - 5 knots? You were not flying a spinnaker and you might have surfed a few waves but 8 knots in a C25? Not likely without the influence of current. Perhaps a 2 - 3 knot current and maybe even more, all setting you to the ENE.
The theoretical hull speed for a Catalina 25' with both sails up should be somewhere around 6.5 knots, which is slightly faster then my 27 footer which has a slightly smaller LWL then the C25.
Did you notice your SOG on the GPS as you headed back in a westerly direction? I'd bet that the same ENE current pushed your speed down closer to 3 knots SOG on the way back.
TomMays posted this link before which gives a nice graphical display of the expected currents in our local waters (for any hour of any day): Stevens Maritime Center: Urban Ocean Observatory

If you had an accurate knot meter you would have seen a difference between your speed through water and your speed over ground (SOG) which would have indicated the speed of the current.

Still a good learning exorcise.
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