On Apr 18, 4:43*am, Stefan wrote:
WingFlaps schrieb:

I see you don't know. In fact an altimeter is calibrated to the
standard atmosphere so if the temp. is not standard it will not read
field elevation when local QNH is applied.

Wrong.

*From The ICAO Manual of Radiotelephony (ICAO Document 9432) Glossary:
QNH: Altimeter sub-scale setting to obtain elevation when on the ground

So an altimeter set to local QNH will always read field elevation *by
definition*.

* Pretty basic knowlege for a PPL

Indeed.

Yes it may say that but it's being loose because it forgt to include
the "barometric pressure reduced to MSL by application of the ISA".
Alltimeters are calibrated for the standard atmosphere. -right?
Think about it, if an ARFOR gives QNH how could it be correct for all
terrain if local temperatures differed? I covered this in my PPL tech
course -was this not covered in your manuals?
just in case you still don't see it, from Wiki:

"The altimeter is calibrated to show the pressure directly as an
altitude above mean sea level, in accordance with a mathematical model
defined by the International Standard Atmosphere (ISA)... An altimeter
cannot, however, be adjusted for variations in air temperature.
Differences in temperature from the ISA model will, therefore, cause
errors in indicated altitude."

OK?

Cheers