Hello,

some airports have procedures like RNAV 30 X, RNAV 30 Y, RNAV 30 Z.

The ATC only gives me RNAV 30, how do I know which one it is? Thanks.

Assuming you did flight planning, then your flight plan would have the name, including the X, Y, or Z modifier in it.

If you get the assignment on a VFR flight where you're going to get vectors to the final approach, then you can assume the Z approach with the lower minimums.

Adding the designation to the clearance is on the list of things for the future.

Dave