With due respect to your experience, Richard, I'm going to disagree! First of all, though, I would like to define what I mean by straight, and this would be 'direct, non-deviating, not bent'. By this definition a great circle is a straight line. It also meets the requirement 'a straight line is the shortest distance between two points', albeit on a spherical surface.
Rhumb lines are not straight lines on the spherical surface nor on any chart projection except the Mercator. Was that a typo?
Last edited by Alex Whittingham; 28th November 2014 at 14:59.
Reason: Edited to say Richard's typo is corrected