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Hi all... and sorry in advance if this subject has already been discussed... but Im considering bringing a 29 foot sailboat down to Ft. Lauderdale from Oriental NC. I have limits on my time away from my job so the time estimate is crucial...

Does anyone have any ideas of how much time I should allocate for this... This isnt going to be a leisurely, stop and smell the roses trip but more like a delivery...
 

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Sailboat Reboot
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Your question has several answers. Assuming you have a displacement hull (that is, you do not have a boat that planes) the theoretical hull speed = 1.34 (sqrt(length of the waterline.)) Note that this is the length of the waterline, not the length of the boat. This is the empirical "maximum speed" through the water. Note that if you have a favorable current you could be achieving more than maximum speed over the ground. On the other hand if you have an unfavorable current you could be going much slower over the ground than through the water. Also note that when traveling at empirical maximum speed any additional force is going to cause the rig to be very unhappy. So unless you have a crew that is trimming for the gusts you would not normally want to plan or travel at empirical hull speed.

OK, so that is the theory. A more useful concept is "average speed of advance." This is an average, over time, of the distance made good by you in your boat over all sorts of conditions. In my planning I use 100 NM per 24 hours. I have had 30 NM days, 150 NM days, etc. but over the long run I average about 100 NM per day. You will only know what it is over time but start at about 75% of your maximum speed. That is a decent guess. Also realize that your style will have an impact. I find a 100 NM per day objective a very comfortable way to sail, I am not going as fast as I could but I like the ride and the fact that I am not trimming all the time.

The average speed of advance falls down for short trips. Lets say I am planning a 5 day offshore transit under sail. That means I intend to go 500 NM. It is very possible that I will get a couple of bad wind days and not make anywhere near my 100 NM plan. If I kept going another 15 or 20 days I would most likely get back to my average but of course I would miss my destination (LOL.) So I never commit to be in a new port on a specific day based on my average speed of advance.

One of the most frequent errors made by new cruisers is they plan to meet someone at a new destination on a specific day based on their estimated speed of advance. Then they get behind because of the weather, start sailing stupid, and break the boat. A far better strategy is to plan to arrive 2 or 3 days before your friends and make sure that they accept the fact that even so you may not be there when they get there.

Fair winds and following seas
 

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I have made this trip several times. Lots of things play into the total time. Do you plan to anchor out or stay at marinas? Some times you have to stop early or push late to make an anchorage/marina. Time of year/daylight and how long can you stand to be at the helm? Crew or single-handed? Inside on ICW, outside or some of both. Does your boat have enough "emmph" to push thru strong currents? What is your draft? Draft and currents can cause you to have to play the tides and that can cost time.
Basic math is Oriental is MM 180+- and Ft L is MM 1065+-. So on the ICW that is just under 900 SM. ICW is measured in statute miles. Use your average MPH, as you will be motoring most of the time in the ditch, times the # of hrs you want/can to travel per day to get how many days. Then factor in some down days for weather/rest. I use 10%, 1 down day in 10.
Dan S/V Marian Claire
 
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