Garmin GpsMap 396 - Flight Test

This would seem to pose a safety risk in IMC, would it not? Ideally,
wouldn't altimeter settings take this into account?

I assume that since all altimeters will behave this way, ATC obviously
expects me to be at, say 10,500 as indicated by my altimeter, even
though that could be 10,900 or so MSL _actual_ altitide..

Seems a bit sub-optimal somehow... even dangerous.

I never thought the effects were so pronounced....

-Dan


Dan Luke wrote:
"Dan" wrote:

Has anyone noticed the GPS altitude and what the altimeter says become
increasingly different as altitude increases? (i.e. 10-12k+)?

This difference seems much more pronounced the higher I go. (Yes, I do
have the correct altimeter setting...) The GPS always seems to read
250-500 feet higher.

Your altimeter is not corrected for temperature. The GPS is not affected.

--
Dan
C172RG at BFM

"Dan" wrote:

This would seem to pose a safety risk in IMC, would it not?

Yes, it could. Extremely low temperatures can be dangerous to low-flying
aircraft because altimeters will read high in such conditions.

Ideally,
wouldn't altimeter settings take this into account?

Yes. Also ideally, I would be flying a new Bonanza.

I assume that since all altimeters will behave this way, ATC obviously
expects me to be at, say 10,500 as indicated by my altimeter, even
though that could be 10,900 or so MSL _actual_ altitide..

Yes.

Seems a bit sub-optimal somehow... even dangerous.

It works fine as long as everyone is using the local altimeter setting.
Watch out near the ground when it's real cold, though.

--
Dan
C172RG at BFM