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Old 30th November 2004 | 15:43
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pugzi
 
Joined: Mar 2001
Posts: 120
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From: Uk
You intend to overfly a mountain range. The recommended minimum flight altitude is, according to the aviation chart, 15000 FT/AMSL. The air mass that you will fly through is on average 15°C warmer than the standard atmosphere. The altimeter is set to QNH (1023 hPa). At what altimeter reading will you effectively be at the recommended minimum flight altitude?
A 14100 FT.
B 13830 FT.
C 14370 FT.
D 15900 FT.

I think this is the questino you are after.

Remember this. For every 1°C deviation from ISA your altimeter is wrong by 4ft for every 1000ft you have.
In this case you have 15°C ISA Deviation. So 15 x 4 gives you 60ft error per every 1000ft. You are at 15000ft so 60 x 15 gives you a toal error of 900ft.
Its "warm" in the question, and when it's warm TRUE ALTITUDE is more than INDICATED ALTITUDE.
So, to have a true altitude of 15000ft the indicated altitude must be 14100ft!!

Ta Da!!

Courtesy of Pilot Ground Training
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