Gee, that was actually a well thought out, well explained, and in my case
anyway, very informative post.

It's been 9 years since my written, but I don't remember a whole lot about
geoid reference in it. I do remember the WSG84 reference in my handheld
(which I never use for altitude, BTW) though, so it must have been there.

mike

P.S. I got a 96


"Stefan" wrote in message
...
mike regish schrieb:
Well, what exactly are their reference datum(s?).

GPS altitude and pressure altitude are completely different and, most
important, *incompatible* systems.

very knowledgeable post snipped

But I'm sure you knew all this before, because after all, you've passed a
written.

Stefan