Garmin 530 Fatal Error

It is not the CDI, the CDI is getting it's right and left from the GPS.


The question at the meeting was. At what point should the IFR GPS
change the right to left and left to right (under the 180 degree
scenario above)? The conclusion was. NEVER! Of course you can push the
direct to button again and all will be well again. But the point is,
IFR GPS units can REVERSE SENSE and most pilots and instructors are not
aware of this how or why or when.

Now to further confuse things, the NEW spec (the spec the 480 is
certified under), the unit automatically corrects for this erroneous
right and left. Sheesh, no wonder everyone is confused! And of course,
so do many handhelds (ones that advertise they have an "HSI" and not an
OBS).

Doug wrote:
It is not the CDI, the CDI is getting it's right and left from the GPS.

What is not the CDI?

The question at the meeting was. At what point should the IFR GPS

What meeting?

change the right to left and left to right (under the 180 degree
scenario above)? The conclusion was. NEVER! Of course you can push the

There is no scenario above(?).

direct to button again and all will be well again. But the point is,
IFR GPS units can REVERSE SENSE and most pilots and instructors are not
aware of this how or why or when.

Now to further confuse things, the NEW spec (the spec the 480 is
certified under), the unit automatically corrects for this erroneous

Are you referring to TSO C146?

right and left. Sheesh, no wonder everyone is confused! And of course,
so do many handhelds (ones that advertise they have an "HSI" and not an
OBS).

Well, my Garmin GNS480 has an HSI (track-based) display, and also an OBS/CDI.
When I'm outbound for a straight-in approach with (say) the approach course on
my right, the HSI display correctly shows that the approach course is to my
right. The CDI gives a "fly-left" indication (that is, the needle is on the left
side of the instrument case). I didn't think this was different from the output
of TSO C127 navigators.

I don't find it confusing, though. That's just the way it works.

Dave