Re: "two main reasons why the Royal Navy no longer uses [paper charts]"
"At school, we had to learn how to do it the hard way [...]"
An autobiography** described a schoolboy's ambition to go to sea. Before being taken on by a shipping company he had to show he could do geometry for a path on the surface of a globe.
We can usually treat the Earth's surface as flat and amenable to Euclidean geometry - where the sum of angles inside a triangle is always 180 degrees. For long distance navigation over a globe that no longer holds true - and the calculations get rather more complicated.
**There are 27 feet length of biographies on my bookshelves. So couldn't spot the book at a glance.
Biting the hand that feeds IT
