We dont have contact with ATC anyway as its a unicom airfield
we are using inertial navigation, so dont need ground based navigation.
We are flying into an airport tonight where the MEA is 12,000 feet, the DME arc is 6,500 feet, distance to FAF from the Arc joining point is 19 nms, FAF altitude is 4800 feet. So allowing 19/3 = 6300 feet plus 4800 = 11,100 feet, our maximum altitude for joining the arc is 900 feet below the MEA. GRID MORA is 8,000 feet. We further compound this by routing direct to the ARC, so the initial arc distance of 9nm is reduced. So if we descend to 9000 feet (due direction of flight), we can join the arc 13 miles from the FAF and we have saved a massive 1 minute of flight time, not bad after 3000 nms
Also the MORA is Jeppesen derived, so they didn't account for navigation coverage, it doesn't mean that it doesn't exist. We are navigating to a high altitude VOR and not a terminal VOR, so the theoretical range is based on height above the transmitter. (1.23√Receiver Ht (in feet) + 1.23√Transmitter Ht (in feet))