Re: GPS altitude on the 60CSx!

Those who fly their own planes should be aware that the Aeronautical
Information Manual says in 1-1-19(a)(8), "GPS-derived altitude should not be
relied upon to determine aircraft altitude since the vertical error can be
quite large."

Bob Gardner

"John Tyson" <johnatyson@xxxxxxxxxxxxx> wrote in message
news:Pmxjh.3361$yx6.2160@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
As a result of recent threads on altimeter usage on the Garmin GPSr's,
I've started running some experiements to get an idea of what exactly is
going on. Although I've just started this and have more ideas than
answers, I've made one astounding discovery:

If you go into the "Fixed Elevation" mode on the 60CSx, it now uses the
GPS altitude for tracks and waypoints instead of the barometric altitude!!

Garmin has apparently implemented this without bothering to tell us, in
spite of numerous threads over the years practically begging them to
implement just such a feature! Go figure.

I was pretty sure I hadn't seen this in the past; I went back to my 60CS,
and it does not do this. I'm not sure I've got the latest software on it,
so it could be Garmin has implemented this on the older models as well.

This is very preliminary, and I might end up with egg on my face, but it
looks very firm to me, and I wanted to get the word out. I urge those who
have been interested in this kind of feature in the past to try it for
themselves -- particullary if you are flying over the holidays :)

Merry Christmas!
John




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