NavList:

Stan K wrote:
"Since Pub. 249 is one of several tabular ways of solving the spherical navigational triangle, I would have to say that it uses a spherical model."

Right. The geometry is worked out on the celestial sphere. And then that perfect, spherical solution is "pulled down" to the Earth's surface using the local vertical. The definition of latitude that we use --on all maps, globes, etc.-- automatically incorporates the Earth's oblateness, including the "pure" gravitational component due to the ellipsoidal distribution of mass and also the centrifugal force in our rotating frame of reference. So it's not Pub.249, or any other form of sight reduction, that compensates for the major share of the "earth's non-spherical nature". Its latitude itself that bears that burden, and it does so in a way that is very nearly invisible to end users.

You see... the Earth is really flat, but us scientists, driven by our allegiance to the Illuminati, use math to make it seem as if the Earth is a sphere.

Frank Reed