AIM 1-1-20 (a)(8) tells us not to rely upon GPS to determine aircraft
altitude.

Bob Gardner

"smf" wrote in message
news:jpblc.12364$bS1.6242@okepread02...
My Altimeter is accurate when on the ground or at lower alt. When I climb
up
to 7k and above and check it against GPS and approach controls read out it
is about 300+ feet off.

Is it the altimeter I'm having problems with?


Steve