One can fly anywhere. One can only commune with the grand canyon in silence at the grand canyon. So, flying should be restricted, by your comment above.

It seems as though you are in favor of being able to view the canyon from a certain perspective; backpacking or hiking in your case.

No, I am using Peter Duniho's reply to my abstract argument to support a
POV that resembles that. However, my argument (somewhat in support of
restrictions) is not based on "permitted perspectives of viewing".
Viewing is hardly the issue - experiencing is of far more depth. The
experience for which the national parks were created (that of unspoiled
wilderness) is adversely impacted by certain activities, such as
superhighways, jetskis, boomboxes, and the like. Airplanes fit into
this category. Gliders probably do not (though their support system may).

Restrict the air routes, and altitude, and make sure there are areas that will not be touched by the sound, but don't eliminate the wonderful perspective that viewing the grand canyon by air provides.

If this could be done, I'd be in favor. I don't know that it can't be
done, and I would love it if it could.

Jose
--
The price of freedom is... well... freedom.
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