Tuesday, April 13, 2010

Scheduling of the Trip

CP (Captain Pete) advised me that the departure date will likely be predicated by the seasonal plans of the Marina, the Royal N.S. Yacht Sqn. south west of Halifax. I am told that the date is not firm but for planning purposes we are departing on Sunday May 2nd. 

We will then sail a track made good of approximately (my estimate from my handy dandy Mapart roadmap) 2500 kms. In the nautical world all distances are measured in nautical miles or nm. The SI (System International) standard nautical mile is 1852 metres exactly. That is the modern definition. So to convert the 2500 km to nm, multiply 2500 by 1000 to get a distance of 2,500,000 metres and divide by 1852 to get very nearly 1350 nm.

CP tells me that we sail at possibly 6 knots (or slower of course). What is a knot you may ask?. Well in ancient times speed was measured by the number of knots on a rope that slipped through the sailor's hands during a specified time when the log that was tied to the rope was thrown in the water and allowed to drift aft. The spacing of the knots was calibrated to indicate the speed. A knot is equal to a nautical mile per hour.

We have scheduled 3 weeks to do the trip but there is absolutely no telling how long it will take or how far we will get. At worst we may not get up the St. Lawrence much past Quebec City, due to dead calm seas and/or head winds and head currents and at best I think we will make it all the way to Picton under perfect conditions.  Under absolutely ideal conditions i.e. perfect wind and maintaining a steady 6 knots, we would do the whole distance in 9 and half days, but that is entirely unrealistic. We need to stop for rests and visits and wait for locks, go through locks etc.

Bear in mind that with a sailboat you can not always sail a straight track along the desired route. One must for example tack or zigzag when we want to sail into the wind. So the real distance traveled over the ground can be much longer than the actual distance traveled along a desired track. In nautical navigation they use all kinds of other unusual terms as well like speed over ground, distance made good etc. I might expand on those later.

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