Paper Charts: A Look at Five Countries
An update on paper charts carryage requirements in the UK, France, Germany, the USA and Canada.
Navigation
On the Closest Point of Approach
The practical use of the CPA/TCPA pair is to evaluate the risk of collisions. If the CPA of a boat is zero (or close to zero), there is a collision risk and the skipper should alter the boat’s current course to increase the CPA.
Is the Fastest Route the Longest Route?
Is it faster to sail downwind a straight line or to gybe from one tack to the other? The answer, of course, depends very much on the boat performance and the prevailing winds. It is however possible to provide some practical guidance with a little use of theory.
What is the sine of one degree?
Prior to the invention of computers, calculators, or even sliding rules, having what is known as a « sine table » was however of critical importance.
How did we find those values?
A Great Celestial Navigation Course
Celestial navigation has the reputation of being complicated, obscure and, depending on your relation to mathematics, bordering black magic.