BOAC, After gazillions of posts where we agree, we finally reach a point of disagreement.....
I said, "
Of Course, if you have the facility to fly TRUE Tracks and/or Headings, it would be a piece of cake!"
And you said, "
- but you would still 'miss' unless you live on a flat earth
"
Ummm, a Rhumb line is a constant
TRUE TRACK n'est ce pas?
If the aircraft has the facility to fly True Tracks, with TRK SEL available and used, a continuous True Track would be flown, the perfect Rhumb line! (The B777 that I fly has this facility, and I'm sure that many other aircraft do too.
Ironically, your reference to "flat earth" is somewhat akin to the intent of the original mercator charts, where the earth was mathematically "flattened". (Meridional Parts and all that). And, of course, a straight line on a Mercator chart is a Rhumb line, i.e. a constant True Track.
Regards,
Old Smokey