Ron Natalie wrote:

Mark Hansen wrote:


You are also required to have available in the aircraft equipment necessary
for navigation along your route, in the event GPS goes out. That sounds
like
VOR to me.


Not if you have the right GPS. But an unchecked VOR is technically not
airworthy, so unless you're going to follow the procedures for inop
equipment, it would be easier just to do it.

Not so. VOR is still the primary means of navigation in the NAS. Even the
latest and greatest airline aircraft with dual GPS sensors, dual FMSes, triple
IRUs, etc, cannot be dispatched without operate VOR receivers (in their case
two).

The presumption is that the GPS system can fail at any time; at least in a given
area. WAAS doesn't mitigate that whatsoever.