Setting altimeters with no radio
Travis Marlatte schrieb:
The discussion was about the life-saving necessity of an accurate altitude
instrument.
Sorry to nitpick, but the discussion was about how to set the altimeter
if you can't get the lastest pressure data with the radio. Some guy
proposed to use the GPS altitude as reference, and then some (other?)
guy stated that you better always fly on GPS altitudes, because it's
more accurate anyway. This was the point when I jumped in and said no,
don't do this.
Only then:
MX was claiming that GPS is inaccurate enough to kill you.
Actually, it can. It's accurate within a few meters (depending on how
"enhanced" it is), but only in some 95% or so of the time and in some
90% or so places (the correct numbers don't matter). Which means that if
you happen to be in the wrong place at the wrong time, believing in the
GPS can actually kill you, at least theoretically. Of course I'm rather
looking out of the window when I fly in VMC, so this isn't an issue in
real life for me.
Stefan
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