Mxsmanic wrote:
Feet and knots are largely dimensionless in aviation. You don't
really have to know how long a foot is, or how fast a knot is. You
just have to plug the numbers in correctly when flying.

Knots are not dimensionless in aviation. A knot is one nautical
mile per hour, and that nautical mile is the distance corresponding to
one minute of latitude at the equator. Anyone using lat/long and some
spherical trig (like the old guys who crossed oceans used sextants to
determine their position) will make use of these things. The lazy ones
among us (or like me, the ones really poor at math) will use GPS, which
does the same thing.


Dan