GPS clearance puzzle

Thanks, John.


"John R. Copeland" wrote in message
...
From page 37 of the GNS 480 Pilot's Guide;
"NOTE: When using the OBS mode with a VOR station, the GNS 480
will use the station declination of the VOR.
For other waypoints, the GNS 480 will use magnetic variation based on
your present position."

In my opinion, it should use VOR station declination *only* in OBS
mode, but in Salem they chose to use it in all modes involving VORs.
That wasn't their original choice, but the UPS pilots wanted it that way.
---JRC---

"Stan Prevost" wrote in message
...
Roy, just curious, does the CNX-80 use the facility magnetic variation
when
setting up a VOR radial in OBS mode? I believe the Apollo GX-60 does not.
I think the 430/530 does use the facility variation, and I wonder if
Garmin
changed what the Apollo units do, either in the CNX-80 or going to the
GNS-480.

There is a four degree difference between facility variation and actual
variation at our local VOR. It would make two miles of crosstrack error
at
30 miles from the VOR, usually not a big deal, but worth knowing about.

Stan

"Roy Smith" wrote in message
...
Apparently, if you file IFR HPN - MMU, you get a clearance which starts
"CMK CMK275R SAX039R SAX" (i.e. fly outbound on the CMK 275 until you
intercept the SAX 039, then fly that inbound to SAX). In the good old
days of 2 VOR receivers, this is trivial to fly; the radios don't know
or care that the cross-radial fix you're going to doesn't have a name.
But, how would you fly that with a GPS?

I've been puzzling over that one for a week or so now, and the best I
can come up with is to use the GPS's OBS mode to track outbound on the
CMK 275, and set up a VOR receiver to indicate the crossing radial.

Can anybody figure out a way to set it up purely on the GPS? I'm using
a CNX-80, but it might be interesting to see how other units would do it
too.