Originally Posted by Walt
I’ve done lots of G5’s and don’t recall ever seeing a large error (maybe 40’ max) so I’d be a little suspect about the reference you’re comparing it to.
The reference might be the issue for me. I flew to an unfamiliar airport and the G5 was dead on the published airport altitude at 5150 using the local AWOS barometric reading. My altimeter and RMI uEncoder both read something different.
My home airport (KBJC) elevations range from 5566' all the way to 5673', depending on location, so I'm not even sure what the exact elevation is at my hangar.