There is only one such IAP in the country (probably the world). If, however, you mean most pilots don't know how to fly DME ARC initial approach segments, then their training is seriously lacking.

Then count me in. I was never taught the procedure; I asked here some
time ago and practiced it on my own. However, my training is not
"seriously lacking". The DME arcs were not around much (DME was not in
the aircraft either) when I took my training. I've kept up, but one
cannot keep up with what one does not know to keep up with, and some of
those things are obscure "gotchas".

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