If a single VOR fails in your area, or worse on your approach, you have a
little to a big problem depending on the circumstances. If a single
satellite fails for the area you are operating you are not likely to even
know it because so many other satellites are still available to provide no
worse than about 60M accuracy.

Uncontested. But a small number of failures is sufficient to bring down
the entire GPS system. A small number of failures is not sufficient to
bring down the entire VOR system. And the issue is the robustness of
the -system-, not the robustness for any individual flight.

I do not claim that one is better than the other. I do claim that the
difference in failure modes is significant, and as you pointed out, can
play either way. That it can play one way does not mean it can't play
the other way, or that the other way isn't a significant factor.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
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