Dead Reckoning Navigation
Even though you may be an inland lake sailor, it is still a good idea to learn about dead reckoning. It is a way to have knowledge of where you are on a chart.
In order to calculate where you are, you must first have the definite knowledge of where you were. So, before you start on a journey, determine where you are on the chart.
To calculate you must use the
following three equations(D = Distance in miles, T = Time in hours and S = Speed
in knots or mph):
However, you might want to calculate in minutes instead of hours. In that case
the formulas are:
1) You are sailing at 14
knots. How far will you go in 40 minutes?
2) Determine your speed.
You leave a known sea buoy and arrive at another known buoy. It took you 40
minutes and you measured on the chart and know the distance is 11 miles.
3) You have a 9.5 mile
reach to your home port and you are sailing at 6.5 knots. How long before
you get home?
Oh Sure! You are asking, "Why learn to do all this when I can use a GPS?" Good question, but learning dead reckoning is a basic that should not be overlooked.., just like learning your A, B, Cs.This helpful boating pointer is provided by Catamaran Sailors Magazine, http://www.catsailor.com/.These tips are useful to boaters of all types. ABA assumes no responsibility or liability for events that occur due to actions you or others on your behalf take based on the information given. You are proceeding at your own risk.