Also, what is the difference between approaches such as:

RNAV (GPS) Y RWY 20
RNAV (GPS) Z RWY 20

Sometimes they look identical I've noticed, is the Y and Z designation
similar to the A in VOR-A, etc?

On Apr 17, 1:59 pm, kevmor wrote:
I'm learning to use the KLN94 IFR GPS and was wondering about using
the ALT button to set the current altimeter setting. I can see why it
would use this for VNAV, but is it required to set it for normal non-
precision approaches? I think the only thing I've read in the manual
so far was it helps to get the RAIM check done faster or something
like that.